Author: jtechtmann

Days one through seventy are the most critical period for developing your future cow. What are you doing to set your newborns up for success?

It seems every discussion surrounding calf raising includes colostrum – that key first nutrient and antibody packed meal, critical to helping protect the newborn for the first weeks of life, until their own immune system can produce protective antibodies. Calves are born without any immunity because antibody proteins are not able to pass through the placental barrier. There are several factors impacting how much immunity a calf gains from the colostrum it is fed. But colostrum also does much more than immunity for the newborn, including things as simple as the delivery of colostrum at an appropriate temperature being important to warming of the calf. Colostrum has been found to contain over 200 bioactive compounds (Blum and Baumrucker 2000) which also affect overall absorption of nutrients, growth, and future milk production (VanAmburgh and Soberon 2016).

Quality & Quantity.The goal should always be the delivery of four quarts of high-quality colostrum into the calf within the first hour after birth. This is because the calf’s ability to absorb antibodies is decreased by 25% already, just four hours after birth and virtually gone by 24 hours of age (Stott et al. 1979). There can be drastic variability among cows regarding the concentration of IgG in their colostrum and an IgG level equal to or exceeding 50 g IgG per liter is the highest quality. This can easily be tested using a Brix refractometer, where a reading of greater than 22% would be the cut off for colostrum measuring above the desired 50g IgG/L. To achieve a good level of immunity, the calf must consume more than 200 grams of immunoglobulin IgG, hence delivering four quarts.

There are several factors that influence colostrum quality, including the dry cow ration and vaccination program. Avoiding short dry periods of less than 30 days, overcrowding or heat stress for dry cows also affects quality, along with getting the fresh cow milked within 1-2 hours after calving. Colostrum quality decreases 3% for every hour of delayed milking. For example, if the cow calves at 6p.m. and isn’t milked until 6 a.m., her colostrum concentration is lowered by 36% because her body is already beginning to make milk (Dumm).

Colostrum should be delivered to the calf at temperature of 95-105^oF (32-43^oC). Absorption will be poor if it is delivered too cool and above 110^oF there is risk of causing burns or irritation to the esophagus and digestive tract. A rule of thumb presented by Dr. Rick Dumm, DVM at the recent World Dairy Expo was to feed 10% of the calf’s body weight in high-quality colostrum at the first feeding, then eight hours later feed another 5% of the calf’s body weight in an effort to consistently achieve desired serum IgG levels.

Good stuff. Immunoglobulins are a common part of any colostrum discussion, but what do we know about them? The normal distribution of immunoglobulins in colostrum is 5% IgA, 7% IgM, and 85-90% IgG. All of these Ig types function together, but IgG is the primary contributor to systemic immunity and also functions within the intestine, where IgM has a major role in preventing septicemia and immunity to enteric pathogens. IgA has a lesser role in intestinal immunity to enteric pathogens, but is still a vital part of the immunoglobulin team (Davis and Drackley 1998).

Colostrum has about twice the level of solids and energy of normal milk, providing the newborn with double the nutrition of regular milk and the IgG found in colostrum are virtually non-existent in regular milk. The same is true for the antibacterial Lactoferrin, which is also present in colostrum at a fairly high level and virtually undetectable in regular milk (Kertz).

Keep It Clean. Absorption can be reduced by stress, including difficult calving, heat, or rough handling or feeding of calves, but another serious source is bacterial contamination of colostrum. There have been several studies that showed colostrum samples exceeding upper limits of 100,000 cfu/ml for total bacteria and 10,000 cfu/ml for coliform (Kertz).

Primary sources of this bacterial contamination have been found to be dirty udders, bacterial proliferation after improper storage, and dirty equipment used to milk, transfer and feed the calf (Godden 2007). Items to keep in mind as critical to reducing opportunities for contamination related to the cow are proper udder prep for milking and not letting calves suckle their dam. Colostrum should not be pooled unless it will be pasteurized prior to feeding. If colostrum will be stored, refrigerate it in a manner that it can cool within one hour to the refrigerator temperature, and don’t store it more than 48 hours in a refrigerator. Colostrum may also be frozen. Whatever the method you choose, be sure to label the colostrum prior to storage with the date harvested and Brix refractometer test reading for quality.

Always wear gloves or have very clean hands when feeding newborns. Whether you choose to let the calf suckle a bottle or use an esophageal feeder is your choice, just get the volume in and be sure all milking and feeding equipment is clean. If your bottles, nipples or tube feeders are in need of replacement, visit calf-tel.com or your local dealer to be sure your equipment is in top condition to care for newborn calves. Here is a study that compared bottle and tube feeding results.

Pasteurization of colostrum can reduce pathogens in colostrum, but it is done differently because the density of nutrients is different from whole milk. The fat content of colostrum can be double that of whole milk, while the protein content can be 4x higher. Therefore, the best results are achieved when pasteurizing at 140^oF for 60 minutes. If colostrum were to be pasteurized at too high of a temperature the resulting thick liquid is very hard to feed or clean off equipment. Cleaning protocols are discussed in detail in our blog article titled: “When it comes to calves—keep it clean!” here in Calf-Tel’s Calf Corner. However, if you are checking cleanliness with an ATP meter, the goal for all milk contact surfaces should be under 100 and a score under 10 is excellent.

Kelly Driver has been involved in the New York dairy industry all her life. In addition to raising dairy calves and replacement heifers, she is the Northeast Territory Manager for Calf-Tel. Feel free to contact her at kellydriver@hampelcorp.com with your calf questions or suggest a topic you would like covered in a future blog.

Sources

• Blum, J.W. and C.R. Baumrucker. 2002. Colostrum and milk insulin-like growth factors and related substances: mammary gland and neonatal (intestinal and systemic) targets. Dom. Anim. Endo. 23:101-110.
• Davis, C.L. and J.K. Drackley. 1998. The Development, Nutrition, and Management of the Young Calf. Iowa State University Press, Ames, IA. p. 179-206.
• Godden, S. 2018. Advances in colostrum management. Proc. Dairy Calf and Heifer Assoc., Milwaukee, WI, p.40-50.
• Dumm, R. 2019, October 2. Colostrum for many other reasons. Presented at World Dairy Expo, Madison, WI.
• Kertz, A.F. 2019. Dairy Calf and Heifer Feeding and Management: Some Key Concepts and Practices. Outskirts Press, Denver, CO. p. 8-15.
• Van Amburgh, M.E. and F. Soberon. 2016. Developing a quality heifer: management, economic and biological factors to consider. Proc. Dairy Calf and Heifer Assoc., Madison, WI, p.37-44.

The temperatures are warming up and it is time to think about ways to manage the fly population around our calf facilities. Flies are the major pest problem for dairy calves and are more than just a nuisance as they can also spread diseases like E. Coli and Salmonella. Flies can also keep calves from resting comfortably, causing them stress and reducing growth rates. And I would be remiss if I didn’t mention that flies present the same challenges to the calf care team. So, let’s talk about some measures than can help create a healthy, stress-free calf zone for all parties.

Identify the pests. Knowing the types of flies that you are dealing with as well as their lifecycle is the first key in developing an effective fly management plan. Stable flies, house flies, and blow flies, all commonly classified as “filth flies”, are the most common types found around dairies. They are labeled “filth flies” because they prefer moist conditions and like to lay their eggs in manure, decaying organic matter, spilled or spoiled feedstuffs, and damp bedding, according to Dairy Herd Management. Other common flies that are more often found in pastures or open areas can include horse flies, deer flies, face flies, horn flies, and even mosquitoes. Several of these pests are biting flies that require a “blood meal” and can be quite disturbing to calves. Sarah Morrison, researcher at W.H. Miner Institute, Chazy, NY, notes that stable flies cause painful bites on the lower legs of calves, damaging their tender skin, even to the point of causing noticeable hair loss and scab formation. (Hanson) House flies are the most prevalent in numbers and while they don’t bite, they are effective carriers of disease. The Cornell University College of Veterinary Medicine notes that the house fly’s life cycle is a quick 10 days, while stable flies complete their life cycle in 3 to 4 weeks. (Bertoldo)

Control Options. While it may feel like fly season is still weeks away, it is much more effective to start fly control measures before flies appear. It is important to develop an integrated pest management plan (IPM) to maximize fly control efforts at your operation. IPM focuses on three key areas: sanitation, biological control, and chemical control. (Hanson) Take the time now to walk around your farm facilities, identifying any fly breeding areas and where maggots might live, then determine how to make these areas less attractive to flies.

Keep it clean. Both house and stable flies breed in manure, decaying silage, and moist bedding or feedstuffs, making sanitation the key management practice. Since the house fly life cycle is just 10 days, cleaning everything possible weekly is most desirable and removing any spilled or leftover feeds daily is also helpful. Spreading manure in a thin layer to promote quick drying can also help. (Bertoldo)

Another important sanitation measure is keeping the bedding in the calf housing area dry. Some farms switch to sand, wood shavings or sawdust as bedding material instead of straw in the warmer months of the year. Opening rear doors and vents on Calf-Tel hutches or pens to encourage airflow will also help keep the bedding dry.

Biological control. Releasing natural predators in the spring months can help keep fly populations from blooming. Parasitic wasps, Muscidifurax raptor, will selectively lay their eggs in the larvae of house and stable flies and effectively prevent it from developing. This is the only species of wasp that is effective against the house fly, according to Cornell University’s College of Veterinary Medicine, and should be released on a weekly basis from mid-May through August in northern states. (Bertoldo) Additionally there are beetles and mites that are also predatory to flies, but “these insects are also subject to the same chemical control effects as the flies, meaning that residual insecticides and larvicides cannot be used in conjunction with parasitic wasp releases”, notes Dr. Gerald Bertoldo, DVM with Cornell’s Pro-Dairy team.

Another option is an insect growth regulator, which is a feed additive that can be added to milk or milk replacer beginning several weeks before the start of fly season. Implementing a feed-through larvicide before flies’ hatch works by disrupting the development of the fly’s exoskeleton in immature flies, killing them so they do not become adult flies. (Dairy Herd Management) This break in the life cycle results in fewer flies buzzing around later and does not require extra time or labor to implement. If these products are part of your IPM, be sure to read the label and feed them until 30 days after cold weather arrives for best results.

Chemical control. At times judicious use of short acting chemical methods may be needed to supplement fly control measures. Long acting residual products can provide an immediate effective knockdown, but a resistance can develop to them. Space sprays and baits are effective and less apt to promote resistance. (Bertoldo) Items like fly bait traps, pour-on insecticides, fly bait poisons and sticky tapes can also work well as part of an integrated pest management plan.

An added perk. An effective fly control program creates a much more pleasant environment for both the calves and the people caring for them.

Kelly Driver has been involved in the New York dairy industry all her life. In addition to raising dairy calves and replacement heifers, she is the Northeast Territory Manager for Calf-Tel. Feel free to contact her at kellydriver@hampelcorp.com with your calf questions or suggest a topic you would like covered in a future blog.

Sources:

• Bertoldo, Jerry, DVM. (Internet). Bedding, bugs and calves: maintaining comfort and health. Retrieved from https://www.vet.cornell.edu/animal-health-diagnostic-center/programs/nyschap/modules-documents/housing-bedding-fly-control
• Dairy Herd Management. (Internet). Fly control strategies for dairy calves and heifers. Retrieved from https://www.dairyherd.com/article/fly-control-strategies-dairy-calves-and-heifers
• Dairy Herd Management. (Internet). Fly population management on dairies. Retrieved from https://www.dairyherd.com/article/fly-population-management-dairies
• Hanson, Maureen. (Internet). Protect your calves during fly season. Retrieved from https://www.dairyherd.com/article/protect-your-calves-during-fly-season?mkt_tok=eyJpIjoiT0RJME1qWTROV0ZsTkRBNSIsInQiOiJcL2RaOWs4YmFNMExRSXRaY0lseWRGbkFkTXVjSkw0M1RJOXRPXC84WVhjYzZTN2pTbStmdk81MkdMRV
• Loftin, Kelly M. & R. Corder. (Internet). Fly Control for Organic Dairies. Retrieved from https://www.uaex.edu/publications/PDF/FSA-7072.pdf
• Purina Animal Nutrition. (Internet). How to get a head-start on fly control. Retrieved from https://www.purinamills.com/dairy-feed/education/detail/how-to-get-a-head-start-on-fly-control

By Margaret Quaassdorff & Casey Havekes, Cornell Cooperative Extension Regional Dairy Management Specialist

Introduction:

It is widely accepted as an industry standard that calves should double their birth weight by 60 days of age. To accomplish this target, or even exceed it, calves must receive a sufficient supply of required nutrients. Often this results in calves being fed high amounts of milk and/or milk replacer. An important consideration when feeding high planes of nutrition is that the more liquid that goes into the calf, the more liquid there will be coming out. Loose manure from calves on a high milk diet can easily be confused with nutritional scours. The first objective of this article is to help calf raisers understand and calculate nutrient requirements. Secondly, the article strives to help calf raisers understand the difference between nutritional scours and normal loose manure, and if action is necessary to improve the health and well-being of these calves.

Energy Requirements of Calves:

A calf’s nutrient requirements can be broken down into the following categories: energy, protein, vitamins, and minerals. Like all growing animals, the nutrients provided to the calf will first go towards maintenance and then any remaining nutrients will go towards growth. So, you may be wondering how we should feed these calves to ensure there are sufficient nutrients available to meet our growth targets. That is an excellent question, and we will attempt to walk you through the steps below to calculate energy requirements, specifically. Please note, that your local Extension Support or trusted advisors are also available to help you. Maintenance requirements for calves can be calculated with the following equation:

MEmaintenance Mcals = 0.1 x BW(kg)^0.75

If we take a 41 kg (~90 lb) calf, for example, her maintenance requirement is going to be 1.61 Mcals metabolizable energy (ME)/day. An important note is that this equation does not consider temperature or breed which are both very important when calculating energy requirements. During cold weather, calves require additional energy to meet their maintenance and growth requirements. Specifically, for every °C the temperature drops below the calf’s thermoneutral zone (15°C or 60°F), the calf’s energy requirement is going to increase by ~0.03 Mcals ME. This may not seem like a big increase, but if you think about a very cold winter day where the temperature is -15°C (5°F), that calf’s energy requirement for maintenance alone is going to be increased by 0.9 Mcals ME (i.e. 0.03 * 30°C difference between thermoneutral temperature and outside temperature).

So now that we understand maintenance requirements, we need to calculate how many additional nutrients are required to achieve growth targets. The energy requirement for growth can be calculated with the following equation:

MEgrowth Mcals = [0.84 * BW(kg)^0.355 * (ADG (kg/d)^1.2)]

If we take that same 41 kg calf and we would like for her to gain 0.8 kg/day, then her growth requirement is going to be 2.4 Mcals ME. Now, if we combine her growth and maintenance requirements (assuming it is a nice spring day with a temperature of 16°C or 61°F), we get a total energy requirement of 4.01 Mcals ME. Once we have a total energy requirement for that calf, we must calculate how much milk or milk replacer is required. We can calculate energy content of milk replacers based on a series of formulas – please reach out to Casey or Margaret, or a trusted advisor if you need help calculating these values. A general assumption is that most milk replacers will have an energy value of ~4.2 – 5.0 Mcals / kg of dry matter (DM), while Holstein whole milk is closer to 5.3 Mcals. If we take a 28:20 milk replacer that is supplying 4.74 Mcals ME / kg DM, we can then calculate how much we need to feed to meet the requirement of 4.01 Mcals by dividing 4.01 Mcals (required) by 4.74 Mcals (supplied). By doing this simple calculation (4.01 / 4.74), we get a value of 0.85. This means that this specific calf requires 0.85 kg of this specific milk replacer to achieve her maintenance and growth requirements. Calculating feeding rates to meet requirements is important; however, it is only one piece of the puzzle. Another important aspect relates to management of these milk-based diets. The remainder of the article is going to discuss key management practices for feeding calves milk and/or milk replacer diets, particularly those on a high plane of nutrition.

Please note, the calculations above are specific to °C and kg, thus °F and lbs cannot be substituted into the equations.

Loose Manure vs Nutritional Scours:

Normal loose manure is often confused with nutritional scours. It is important for those who raise calves to be able to distinguish between the two. True nutritional scours is diarrhea (excessively and abnormally loose or watery stool), and has negative consequences for the health and growth of our calves. It can be caused by a number of management practices associated with the composition, cleanliness, mixing, prepping, or delivery of milk or milk replacer. It differs from normal loose manure that is typical in calves fed a high plane of nutrition (10+ liters/day) of properly mixed and delivered milk or milk replacer. Nutritional scours is the result of digestive upset, not merely volume of milk going through a calf’s system. More milk in means more liquid manure coming out. A calf with loose manure that is otherwise alert, healthy, growing, and showing no signs of dehydration (i.e. sunken eyes, poor suckle reflex, lethargy, depression) is not suffering from nutritional scours.

Figure 1. This is normal manure from a calf on a high plane of nutrition. Without knowing further background information about the calf, it could also be a sign of nutritional scours.

Causes of True Nutritional Scours:

• Excessive lactose in the milk replacer (>300 grams/day or >0.75% of body weight)
• Poorer quality milk replacer (those that incorporate primarily alternative proteins from plants vs milk proteins)
• Incorrect mixing of milk replacer or additives (undermixing leaving clumps of powder still intact, overmixing causing particles to crash out of solution, wrong mixing temperature)
• Incorrect dilution or percent total solids (too low or too high)
  • Cows’ milk: 12.5%
  • Acceptable range for milk replacer depending on volume fed: 12%-15%
• Inconsistent dilution (a 1% change in total solids is enough to cause digestive upset; example: 14% solids one meal, 12.8% next meal, 14.2% following meal)
• High bacteria load due to:
  • Improper storage of milk or mixed milk replacer
  • Dirty pasteurizer or buildup in autofeeder tubes or nipples
  • Dirty bottles/buckets or mixing utensils
  • Milk from cows with mastitis or high somatic cell count

How to Troubleshoot:

• Calf appearance
  • Monitor signs of dehydration and perform the “Skin Tent Test” as shown in the picture below:

Figure 2. Evaluate dehydration in calves using overall appearance and the “Skin Tent Test”

• Cleanliness audit
  • Work a trusted advisor to get proper tools to identify high risk areas
• Check for quality ingredients on the milk replacer tag
• Follow directions on the bag for mixing (can be specific to the type of milk replacer)
• Weigh both powder and water, and use a refractometer to check total solids % in milk or milk replacer. Make adjustments accordingly:
  • BRIX % +2 = total solids % for whole milk
  • Check with nutritionist for the correct adjustment for your specific variety of milk replacer as they can differ

Figure 3. Description of equations used to calculate percent total solids of milk replacer

• Place a thermometer in the pipeline or near the sink to check mixing and delivery temperature accuracy
• Keep records during feedings (test and write down % solids, and any health observations)
• Monitor the color of manure (Note: Some pathogenic scours can be whitish in color as well, such as rota- and coronavirus, so color alone is not a diagnosis)
• Perform a fecal culture (work with your veterinarian to determine/rule out possible pathogen presence)

What Else Helps?

• Continue feeding calves throughout their bout of scours
  • Calves’ bodies and immune systems need nutrients to fight pathogens and for continued growth
• Direct-fed microbials and prebiotics
  • Promotes, supports and strengthens immunity
  • Common ingredients include:
    • Hydrolyzed yeast cell wall products (intestinal integrity)
    • Beta-glucans from live yeast (primes the immune system)
    • Beneficial bacteria such as Bacillus subtilis (inhibits bad bugs)

Conclusion:

In summary, in order to meet growth targets and performance goals calves require sufficient nutrients. Calculating these requirements can appear to be overwhelming, but please reach out to one of us, or your trusted advisors for assistance. It is also important to remember that the information provided in the first half of this article is exclusive to nutrients supplied by liquid feeds. Providing solid feed is equally important (and now a requirement for the FARM 4.0 program starting at 3 days of age!) in promoting growth and overall success during the pre-weaned phase of life. Feeding calves high amounts of milk or milk replacer in order to meet elevated growth targets/goals can often result in loose manure. Normal loose manure is often confused with nutritional scours, but it is important to understand that properly feeding more milk to calves shouldn’t result in nutritional scours as we’ve described it here. If you suspect that true nutritional scours is affecting your calves, it’s time to find out why.

To watch the webinar recording of this topic and others in the Critical Calf Care series visit: https://www.youtube.com/playlist?list=PLBMGyzTr13d…

Margaret is the regional Dairy Management Specialist for Cornell Cooperative Extension’s Northwest New York Dairy, Livestock and Field Crops Team. She provides dairy producers with technical and practical resources in the areas of production and nutrition management, calf care, and precision dairy technologies to improve herd management and cow health. To contact Margaret, email maq27@cornell.edu and refer to the NWNY Team’s website and/or blog.

Casey Havekes is a Dairy Management Specialist on Cornell Cooperative Extension’s North Country Regional Ag Team. Casey’s recent focus has been on calf health, management and nutrition, transition cow management, and lactating cow nutrition. For more information please refer to the Team’s webpage and/orblog, or reach out to Casey at cdh238@cornell.edu.

By Megan Wildman, Purina Calf & Heifer Specialist

When choosing the right milk replacer for your calves, start with your goals for the calves. Do you want your calves to get the most growth possible during the most efficient stage of life? Are you trying to boost their immunity because you’re fighting a disease challenge? Are you trying to help them gain through extreme heat or extreme cold? It’s helpful to ask yourself these questions.

What’s the outside temperature?

Young calves have a thermal neutral zone between 60-75°F. Calves may undergo cold stress at temperatures below the thermoneutral zone. Calves less than three weeks of age can experience cold stress at 60°F, and calves older than three weeks of age can experience cold stress at 42°F1.

If calves don’t get enough energy in their diet during cold stress conditions, they will use their body fat as an energy source. Energy will be diverted from supporting growth and immune function to maintaining core body temperature. As a result, calves may experience weight loss and impaired immune function. The volume of liquid nutrition required for calves to achieve 1.5 lbs. average daily gain (ADG) varies under different temperatures1 (Table 1).

Do you increase feeding rates in winter?

Increase the quantity of milk or milk replacer to meet the increased caloric needs of cold stressed calves. Adding a third feeding (preferably late at night) is a great way to deliver added nutrition. If already feeding calves three times a day, increase the volume at each feeding. Keep the solids concentration the same and bump up the total volume of the solution. Feed a full potential diet of at least 2.5 pounds of milk solids from 8-12 quarts of milk or milk replacer per day.

It’s important to have the correct protein to fat balance when increasing the quantity of milk replacer fed. The traditional method of feeding approximately 2 quarts of 20:20 milk or milk replacer twice a day falls far short of the energy requirements needed to support both maintenance and growth of young calves, especially in colder temperatures. To increase energy levels, look for a milk replacer with at least 26% protein and 20% fat. Milk replacers with more than 20% fat may decrease growth and hinder starter intake, especially when temperatures moderate (Table 2).

Are you providing the right energy sources?

The energy in milk or milk replacer is predominately derived from two sources – carbohydrates and fat. The predominant source of carbohydrates in milk or milk replacer is lactose. Milk replacer is generally comprised of about 35-45% lactose. Carbohydrates are rapidly digested and provide nearly instant energy, while fat is stored for longer-term use and is a reserve energy source mobilized as needed.

The source of fat in milk replacer is an important and often-overlooked consideration. Milk fat, due to its high value in the human nutrition market, is not typically added to calf milk replacers, leaving alternative sources to supply fat such as lard, choice white grease or tallow.

The fatty acids that make up fat are classified as short-chain, medium-chain, and long-chain fatty acids. The length of the chain depends on the number of carbon atoms in the structure of each fatty acid. Medium-chain fatty acids are highly digestible, as they are absorbed directly from the small intestine to the liver, where they are converted to available energy.

Certain polyunsaturated fatty acids (omega-3s) modulate the inflammatory response by the calf’s immune system, allowing the calf to recover more quickly from an immune challenge. The key to optimizing fatty acids in milk replacer is to mimic levels present in cow’s milk. While most cow’s milk fat is made up of long-chain fatty acids, it also contains 8-12% medium-chain fatty acids.

Are you supporting your calves’ microbiome?

Calves are born with a sterile gastrointestinal (GI) tract – essentially a blank slate ready to be populated with microorganisms. Establishing a healthy, balanced gut environment as soon as possible is critical to the health and development of pre-weaned calves.

The gut microbiome (or gut microorganism population) plays an important role in calf health, as 70% of the calf’s immune system resides in the gut.

The gut microbiome plays an important role in disease prevention and maintaining calf health, especially during times of stress when there is higher susceptibility to disease. Feeding probiotics pre-weaning can help establish a healthy microbiome and support immune strength. Research showed probiotics can help optimize bacterial diversity in the gut that may help address health challenges.

A healthy gut microbiome helps:^1,2

• Promote and maintain calf immune system health.
• Prime the immune system to stay alert and prepared for disease challenges.
• Stimulate mucous layer production on the intestinal wall to provide a barrier against pathogens.
• Enhance the gut immune response to invading pathogens.
• Saturate the colonization sites on the intestinal tissue.
• Break down nutrients for optimal absorption.

Do you provide fresh water?

Water is equally as important in cold temperatures as it is in the summer heat. Dry winter air can dehydrate calves. Providing adequate water supply helps improve hydration and supports growth by optimizing calf starter feed intake.

Offer warm water to calves immediately after each milk replacer feeding and let them drink as much as they want. Make sure water is 100-105°F to avoid lowering calf body temperatures. For those feeding milk or milk replacer two times a day, add a third water feeding mid-day to help optimize starter intake.

Megan Wildman is a calf and heifer specialist with Purina Animal Nutrition in New York. She joined Purina after working as the Cornell University Research Center herd assistant. While at Cornell, she earned a bachelor’s degree in animal science. She’s a sixth-generation dairy farmer and wants the best for you and your calves. You can learn more about Purina calf products at https://www.purinamills.com/.

¹ Corbett, R. Prime the pump. Bovine Veterinarian. April 22, 2019
² Direct-Fed Microbials (Probiotics) in Calf Diets. Bovine Alliance on Management and Nutrition. 2011

Compiled by Kelly Driver

Have you ever heard the phrase “where there is a will, there is a way?” In this post, I will share some of the most useful and innovative ideas I have come across while visiting with calf raisers. Many of these ideas came about as people pondered a better, more labor efficient way of caring for their youngest herd members. At Calf-Tel our slogan is “Heart Meets Smart” and I believe sharing these ideas epitomizes that slogan. May they be ideas that help bring efficiency…or better yet, spark an idea that makes your workday a bit easier.

Hutch Movers

Pictured here are two different styles of hutch movers that have been built. Both of them easily attach to the front end of a skid loader or tractor and can be carefully inserted into the front door opening on Calf-Tel hutches to lift the hutches and move them for cleaning and disinfecting between calves.

Pen Wash Racks

A farm in Wisconsin built these clever wash racks for moving and cleaning their Calf-Tel pen pieces between calves. The racks can easily be picked up and moved by a tractor with pallet forks and returned to the barn for use with the next group of calves.

Marking Calf Pens

Here are just two ways that I have seen to mark calf pens, with different colors of bands, pins or tape indicating whether a calf is being weaned, treated, getting electrolytes, or requires extra monitoring because of a difficult birth. Calf-Tel is now offering pen stickers that can be placed on pens to help track calf information and notes as well. Find them here: Calf-Tel.com

Calf Mover

This is one of the easiest ways we have seen to move calves from the maternity area to the calf hutches or barn. This box can be lowered to ground level to load and unload the calf easily, saving any heavy lifting by the calf care team.

Windbreak

This simple windbreak is made from a piece of shade cloth and placed on every fifth hutch in a row and the calf team tells me they really help keep the snow from drifting in the front opening of the hutches and provide a nice windbreak for the calves. Each end of the fabric is attached to a piece of 2’X4’ lumber to weigh it down and hold it in place.

Tethering Hutches in Windy Areas

If your hutches are located in a windy area, this idea might be helpful. A calf team fastened this cable catch to the top of each hutch in the row. They ran the cable the length of the whole row and fastened it to stakes in the ground at each end.

Feed Savers & Rain Covers

Are you tired of tossing away grain that gets wet in the rain? Calf-Tel offers a feed saver hood (pictured at the right) that easily attaches to the fence in front of the hutch, keeping calf starter better protected from the elements. Are you feeding weaned calves at outdoor troughs? This calf raiser cut leftover pieces of milking parlor wall board wide enough to help keep the rain from filling the trough with water. They find the calves waste much less grain with these in place.

Portable Scales

Weighing calves provides accurate birth and weaning weights to assess our calf program. On the left is a portable scale that can be easily moved with a set of pallet forks on a small tractor. The 3 side walls help keep the calf on the scale for an accurate weight, even when they are still wet after birth. The larger scales on the right are also mounted on a floor that can be easily moved by a tractor with pallet forks, making it very easy to move them to different groups or pens at the calf ranch.

Ease of Working in Calf Barns

These two ideas can save a lot of walking for the calf care team in a calf barn. On the left, this farm left an alley behind the pens that is wide enough to push a bedding cart down, allowing them to bed the pens from the rear while the calves are drinking their milk at the front. The calf care cart on right carries everything the calf team needs as they monitor calves each morning. The rolling cart carries gloves, colored pins for marking individual pens, hand sanitizer, medications, a tube feeder, and a book for recording any observations or treatments.

At Calf-Tel we are passionate about helping calf raisers accomplish their goals easily. If you have tips and ideas that you would like to share with others, please email them to kellydriver@hampelcorp.com and be sure to follow Calf-Tel on Facebook.

Kelly Driver, MBA has been involved in the New York dairy industry all her life. In addition to raising dairy calves and replacement heifers, she is the Eastern US & Canada Territory Manager for Calf-Tel. Feel free to contact her at kellydriver@hampelcorp.com with your calf questions or suggest a topic you would like addressed in a future blog.

by Kelly Driver

The newborn dairy calf is born into a dirty environment filled with bacteria, germs, viruses and a host of other microorganisms that can cause disease. This makes the first, critical delivery of antibodies from high quality colostrum so important to setting the calf on a healthy path because the cow’s placenta does not allow the transfer of essential antibodies in-utero. This systemic protection provided by colostrum in calves lasts from 2 to 12 weeks, depending on the quantity and quality of colostrum the calf received, the disease, and the level of exposure the calf is challenged with (Faries).

Additionally, producers have the opportunity to use vaccines to further bolster antibody levels in the calf. Let’s take a quick look at some things to keep in mind when developing a vaccination protocol with the herd veterinarian.

Types of Immunity

The purpose of vaccine usage is to protect the herd from harmful diseases, but to do this the animal’s immune system must develop memory. With each vaccination and booster, the goal is to provide the necessary protection by triggering the immune system to recognize the disease.

There are two basic types of immunity: passive and active. Passive immunity is immediate as it begins working as soon as the antibodies are absorbed, but this type of immunity is also quite short lived. Passive immunity typically offers about one week of protection, according to Dr. Rob Lynch, DVM in Cornell University’s Pro-Dairy Calf and Heifer Management course. He notes that passive immunity may be reactive, but the body doesn’t develop a long-term resistance and typically these products offer about one week of protection, according to Dr. Lynch (Lynch, 2020).

With active immunity, the body may have a delayed response, taking a few weeks to develop the immunity, but the results can last months or years. Modified live vaccines, bacterins and toxoids can all stimulate active immune responses.

Dr. Scott Nordstrum, DVM, associate technical director of ruminant life cycle management at Merck Animal Health, explains that calves have three basic sources for their immunity:

1. Maternal antibodies from colostrum provide passive immunity for disease protection. This is essential to protect a newborn for at least the first two to four months of life. As time passes, these maternal antibodies dissipate.
2. Innate immunity is the built-in response to disease challenges that nearly all healthy animals are born with.
3. Active immunity is protection from disease developed after exposure to disease or through vaccinations.(Source: Ryan)

Developing a Vaccination Protocol

Considering the possible diseases your calves and heifers could be exposed to is a great way to kick off a risk assessment with your herd veterinarian. It is also beneficial to consider where and when it will be easiest to safely handle the animals and get vaccinations completed on a regular basis. What additional labor may be required to complete the task?

After the thorough risk assessment is completed, work with your veterinarian to select vaccines. Giving consideration to safety, timing of vaccinations (and any necessary boosters), efficacy of the vaccine, and proper handling should all be included. Taking the time to read the vaccine information insert can provide many of the details about dosage, age and pregnancy status, proper storage, route and frequency of administration, and volumes of other valuable information.

Types of Vaccines

In general, there are three types of vaccines: Modified live, killed/inactivated, and a combination of both. The University of Minnesota Extension provides a nice explanation of each:

Modified live vaccine (MLV)

• MLVs are non-disease-causing versions of a virus or bacteria.
• The live virus or bacteria replicate in the animal similar to how the actual disease would, but does not cause the disease itself.
• The replication of the vaccine organism allows the immune system to develop a full response and create proactive immunity with only one dose of the vaccine.
• Many protocols recommend revaccination because not all animals respond to each vaccination.

Killed vaccines

• Killed vaccines do not contain a live virus or organism.
• Killed vaccines contain a dead organism or a specific piece of an organism that is critical to the function of the disease-causing virus or bacteria.
• The crucial difference between killed and modified vaccines is there is not replication with a killed product.
• For most vaccines, the lack of replication means the immune system does not develop the protective memory with just one dose and requires a booster.

Combination vaccines

• Some vaccines contain both modified live and killed products.
• These vaccines can protect against the live portions with one dose.
• The killed portion requires a booster to provide protection.

(Source: University of Minnesota Extension)

Intranasal Vaccines Often Used in Young Calves

One of the challenges encountered when vaccinating young calves is that they have received maternal antibodies that help protect them, but those same maternal antibodies can also neutralize antigens from an injectable vaccine, according to Dr. Nordstrum. “This is referred to as maternal antibody interference. We want to work with the colostrums – not against them. Peer-reviewed research suggests that maternal antibodies can inhibit the immune response to a vaccine in calves until their decline by 6 months of age” (Ryan).

Using an intranasal vaccine actually stimulates a different immune response in cattle. “One of the reasons we love intranasal vaccines is that they are demonstrated to be effective in the face of maternal antibodies because the antigen is introduced in close proximity to the mucosal surfaces,” Nordstrum explains. “They stimulate nonspecific immunity at the mucosal surfaces that helps provide protection against the respiratory pathogens found in the vaccine” (Ryan). This makes intranasal vaccines a good match for young calves and helpful to calf managers battling respiratory challenges.

Common vaccinations for calves and heifers

The central group of vaccines included in any vaccination protocol should be determined with the herd veterinarian during a risk assessment discussion. Often times the diseases are categorized by the body system they affect, such as respiratory or reproductive viruses and bacteria. Another group that may be included in a protocol address clostridial bacteria resulting in diseases like Blackleg, Redwater, and Tetanus.

Scours vaccines may be included in the protocol for pregnant animals prior to calving. Serum antibodies begin to move to the animal’s mammary gland 5-6 weeks prior to calving as part of colostrogenesis. The timely administration of scours vaccines can help provide very beneficial antibodies to the newborn calf through the resulting colostrum, as noted by Dr. Lynch in the Cornell Calf and Heifer Management course.

Handle with Care

Be certain to read labels and store vaccines properly. If vaccines need to be reconstituted, mix them gently. Shaking the bottle could release endotoxins. Several vaccines typically should be in refrigerated storage between 35-45^oF and anytime outside that range can begin to break down the vaccine. Be prepared to keep vaccines out of direct sunlight and in a cool container while using them. In warm weather conditions the challenge is to maintain the vaccine’s effectiveness.

Remember that vaccines are not absolute protection and offer a small piece in helping the host animal. They can aid in the prevention of clinical disease, by triggering the immune system to recognize the disease the animal is exposed to and respond, if the environment and pathogen load are not too overwhelming. A good vaccination program should go hand-in-hand with all the other measures taken to keep calves healthy – proper hygiene, excellent nutrition, and regular consultation with the herd veterinarian.

Kelly Driver, MBA has been involved in the New York dairy industry all her life. In addition to raising dairy calves and replacement heifers, she is the Eastern US & Canada Territory Manager for Calf-Tel. Feel free to contact her at kellydriver@hampelcorp.com with your calf questions or suggest a topic you would like addressed in a future blog.

References

• Armstrong, Joe, DVM. 2020. Cattle vaccine basics. University of Minnesota Extension. Retrieved at Cattle vaccine basics | UMN Extension
• Faries, Floron C., Jr. Cattle vaccines. Texas A&M Agrilife Extension. Retrieved at Cattle Vaccines – When should you vaccinate cattle? (tamu.edu)
• Leadley, Sam. Vaccinating calves in hot weather. Attica Vet Associates. Retrieved at VACCINATING CALVES IN HOT WEATHER (atticacows.com)
• Lynch, Robert A, DVM. November 2020. As presented in Cornell University Pro-Dairy Calf & Heifer Management Course.
• Ryan, Jennifer. (June 2020). The nose knows – internasal cattle vaccines. Veterinary Advantage. Retrieved at https://vet-advantage.com/vet_advantage/the-nose-knows-intranasal-cattle-vaccines/

by Kelly Driver

It is widely recognized that colostrum is the single most important meal for newborn dairy calves, delivering essential nutrition, immunoglobulins (Ig) and other important factors vital to setting up a newborn for lifetime success. Highly anticipated new recommendations about passive immunity standards for newborn calves have been published in the August 2020 issue of the Journal of Dairy Science. So, let’s take a look at what research has shown over the years and what the most recent recommendations offer for both individual calves and herd-level goals, as the industry moves again to further improve calf health and reduce morbidity and mortality in young calves.

The back story.

Passive immunity in dairy calves is evaluated by measuring the serum total protein (STP) or plasma IgG within the first seven days of age. The standard for individual calves to be categorized with successful passive transfer for the past 30 years has been >10 g/L serum IgG, while failure of passive transfer of immunity (FPT) was a serum IgG concentration <10 g/L. These levels correlate directly to STP levels of >5.2 g/dL (pass) and <5.2 g/dL (fail).These cutoffs were established based on higher mortality rates in calves with serum IgG <10 g/L.

Studies have shown.

Research conducted by USDA National Animal Health Monitoring System (NAHMS) in 1991 showed that 41 percent of U.S. dairy calves had failure of passive immunity. With education and outreach, NAHMS reported an improvement to 19.2 percent of calves in 2007 and 13.7% in 2014 studies. Over this same time period, preweaned death rates decreased from 10.8% in 1996 to 6.4% in 2014, but the number of sick calves remained at nearly 30 percent.

Jason Lombard, DVM, MS at USDA/NAHMS reported at the 2020 Dairy Calf and Heifer Conference that in the spring of 2018, a group of eighteen U.S. and Canadian calf experts first gathered to scrutinize the 2014 NAHMS calf data, and discuss other published literature to propose new passive immunity standards. The group emphasized that new standards “needed to be realistic and achievable,” related Lombard to the virtual attendee audience.

Time for an upgrade.

Research has repeatedly shown that healthier calves have improved rates of gain and feed efficiency, resulting in earlier breeding and calving, along with better first and second lactation milk yields. Studies in both dairy and beef calves have also shown reduced morbidity in calves with higher serum IgG levels. Lombard reported the industry group consensus includes four categories, each with corresponding serum IgG concentrations, serum total protein, and Brix percentages. Additionally, the group recommended the percentage of calves that should fall into each category, based on the 2014 NAHMS calf study.

New transfer of passive immunity goals for U.S. dairy calves

Lombard’s group went on to provide two colostrum feeding recommendations, based on the results of the NAHMS Calf Component survey, to help dairy producers achieve the new passive immunity recommendations:

• A single feeding of colostrum, delivering approximately 300g of IgG, fed at approximately 2 hours after birth, or
• Feeding multiple colostrum feedings and delivering approximately 400g of total IgG in the first 24 hours. (Lombard, 2021)

With nearly 90 percent of calves now meeting the previous pass/fail standard of 10 g/L for serum IgG concentration, that standard was successful in challenging dairy producers to improve their newborn calf protocols and colostrum management. Are you ready for the new challenge to further improve calf health and dairy farm success?

Kelly Driver, MBA has been involved in the New York dairy industry all her life. In addition to raising dairy calves and replacement heifers, she is the Eastern US & Canada Territory Manager for Calf-Tel. Feel free to contact her at kellydriver@hampelcorp.com with your calf questions or suggest a topic you would like addressed in a future blog.

References

• Godden, S.M., J.E. Lombard, and A.R. Woolums. 2019. Colostrum management for dairy calves. Vet. Clin. North Am. Food Anim. Pract., 35:535-556.
• Lombard, J. (2020, April 8). New passive transfer standards for dairy calves and how to achieve them. Presented at Dairy Calf and Heifer Association Conference.
• Lombard, J.E., N. Urie, F. Garry, S. Godden, et al. 2020 Consensus recommendations on calf- and herd- level passive immunity in dairy calves in the United States. J. of Dairy Science, 103:7611-7624.

by Sarah Morrison, Ph.D., W.H. Miner Institute

In the first three days after calving, the milk a cow produces changes in composition as it transitions from colostrum to whole milk. This transition takes approximately six milkings after calving (or three days) for this transition to occur. Transition milk provides less concentrated nutrients and bioactives than colostrum, but is still more concentrated than whole milk.

A bioactive is defined as a component that has biological effect.This is an umbrella term, but has received quite a bit of buzz as of late.Bioactives in milk or colostrum can include proteins, fatty acids, hormones, etc. that do not necessarily directly contribute to the nutrition of the calf but can interact with the calf, either at a local level (i.e. the gastrointestinal tract) or systemically for more whole-body action once absorbed by the calf.Furthermore, the extra nutrients in colostrum and transition milk can support growth of the calf and the gut to aid in earlier development.

A study from Michigan State University evaluated the effect of feeding either milk replacer, transition milk, or a 50:50 mixture of colostrum replacer and milk replacer from day 2 to 4 of life. The calves were fed two feedings of colostrum replacer for their first two feedings after birth.Then on day 2 of life, calves started being fed the treatments three times a day with 2 quarts (1.89 L) per feeding. The treatments were milk replacer [27.8% CP and 10.3% fat dry matter (DM) basis which provided 1.17 Mcal metabolizable energy (ME) per feeding], pasteurized transition milk (25.9% fat, 41.8% protein DM basis, and 1.5 g/L IgG as fed, which contained 1.44 Mcal ME per feeding), or a 50:50 mixture of milk replacer and colostrum replacer which provided 14.6% fat, 38.6% protein DM basis, 15 g/L IgG, with 1.28 Mcal of ME per feeding).The figure shows fat and protein provided by the different feeds reported in this study.

The nutrient composition and IgG measured in the transition milk before pasteurization was higher than after pasteurization.This is likely a result of the pasteurization technique used.In this study, they pasteurized the transition milk at 161°F (71.7°C) for 15 seconds, which likely denatured some of the proteins in the transition milk.Recommendations from work done by Dr. Sandra Godden would indicate best practices of heat treatment for colostrum to be 140°F (60°C) for 60 minutes because of the IgG and high solids content.At Miner Institute, we have also heat-treated transition milk following recommendations for colostrum because of the higher solids content.

After four days of age, the calves were fed and managed similarly and body weights, blood samples, and health scores were measured throughout the preweaning period.

Calves that were fed both the transition milk and the 50:50 mixture had an increased body weight of 6.6 lb (3 kg) at the end of the preweaning period compared to the milk replacer group.The calves fed only milk replacer gained 1.23 lb/d (0.56 kg/d), while calves fed the transition milk and 50:50 mixture gained 1.37 lb/d (0.62 kg/d).

The different energy density between the diets fed from day 2 through 4 accounts for some, but not all, of the difference in gain.The authors estimated that the additional nutrients consumed by calves fed the transition milk and the 50:50 mixture would account for 2.84 lb (1.29 kg) of the gain for calves fed the transition milk, and (1.26 lb) 0.57 kg for the colostrum replacer mixture.Therefore, the difference between growth among the treatments would have been residual effects after the treatments ended on day 4 of age.There were no differences in health, with overall incidence of disease very low in all groups.Colostrum and transition milk have been shown to promote the maturation of the intestine, increase absorptive capacity and digestive efficiency. Therefore, some of the difference observed from feeding transition milk or colostrum replacer could be from the other bioactives and their action on development.

We continue to learn more on this topic; however, it seems like there are beneficial effects of feeding transition milk to calves in the first couple of days after colostrum feeding.As with colostrum, it is important to feed clean transition milk that is free of contamination either through heat treatment or good hygiene techniques.

Sarah Morrison, Ph.D. is a Research Scientist at the William H. Miner Agricultural Research Institute in Chazy, NY.Sarah grew up on her family’s dairy farm in Addison County, Vermont.She has a Bachelor’s of Science degree in Animal Science from the University of Vermont and a Master’s of Science and a Ph.D. from the University of Illinois.Her research at Miner focuses on dairy cattle nutrition and management, with a focus on calves and heifers.She can be contacted with questions at morrison@whminer.com.

Reference

Van Soest, B., F. Cullens, M. J. VandeHaar, and M. Weber Nielsen.2020.Short communication: Effects of transition milk and milk replacer supplemented with colostrum replacer on growth and health of dairy calves.J. Dairy Sci. Article in press.

by Kelly Driver

Providing the newborn calf with colostrum, ideally within the first 4 hours of life, is vital to helping it achieve passive immunity. But have we considered what to do when good quality maternal colostrum is not available? A good quality colostrum replacer can provide the healthy alternative.

Failure of passive transfer is big risk. Calves that experience failure of passive transfer (FPT) are more likely to become sick or die in the first two months of life than calves that have adequate immunity. FPT is defined as a blood IgG level less than 10 mg/mL at 24-48 hours after birth. There are many factors that can influence FPT, but the most common revolve around colostrum quality, management, and feeding. Research shows that calves should be fed a minimum of 100 g of IgG within 4 hours of birth, and feeding 150-200 g of IgG is generally recommended to assure plenty of IgG is available for the calf to absorb. (Penn State) We also know that there is a lot of variability in colostrum quality between individual cows, so all colostrum should be tested to ensure only the desired quality is being fed to newborn calves. When available colostrum is low in quality, calf managers may decide to feed either a supplement or colostrum replacer.

Is it a Supplement or Replacer? Colostrum replacers are made from either bovine colostrum or serum and contain 100-150 g of IgG per dose. These products also provide fat, protein, vitamins and minerals, but there is variance among products on the market. For example, fat content can vary widely, but a colostrum replacer will provide more immunoglobulin to the newborn than a supplement product or poor-quality colostrum. When reading the labels, you may find products labeled as “real” colostrum, meaning they contain dairy cow colostrum that has been dried down and heat-treated to eliminate harmful operatives like mycoplasma or Johne’s disease. Serum-based products are the result of blood collected to serve as the antibody source for the newborn calf. These products can transfer IgG to the calf, but can be lacking in the other maternal cells and hormones that are so vital to the newborn calf’s immune system.

There is no way of guaranteeing the effectiveness of a product unless it has been licensed by the USDA Center for Veterinary Biologics. Colostrum supplements are products that are unable to raise the blood concentration of IgG above 10 mg/mL for calves. These products may be used to increase the amount of IgG fed to calves when only lower quality colostrum is available. However, research has shown that when a supplement is added to low quality colostrum, the IgG is often absorbed poorly and FPT rates are higher as shown in the table below. This table summarizes the results of 26 different research trials published in peer-reviewed journals that used nearly 90 different treatments studying colostrum replacer and supplement products and provides a good overview of the various categories performance on average.

Be certain to read the label. Too often colostrum products are selected solely on price, but with many different products on the market, it is very important to look at the labels closely. Since IgGs are the antibodies that provide the newborn calf’s early defense against pathogens, it is important to find a product that guarantees a specific IgG level. Some products may be labeled as providing 120 grams of globulin protein, but in fact deliver less than the crucial 100 g of IgG needed for the calf’s immunity. Globulin proteins actually include other proteins along with the IgG antibodies, so the number can be misleading of the actual effectiveness of the product.

Read and follow the manufacturer’s instructions for feeding. Some products are mixed with water and others are added to existing colostrum, and the number of feedings recommended can also vary. Other products, including those packaged in bulk, offer the option of selecting the IgG dose by using different amounts of powder.

The difference in IgG dosage was studied by Godden et al., (2009a), to determine whether feeding two doses of a colostrum replacer (CR) had further benefit to IgG levels in calves and whether the benefits included all classes of IgG. Each treatment dose contained an IgG concentration of 66.7 g/L, so treatment one received 1.5L and treatment 2 was 3L by volume fed. Treatment group 3 was fed 3.8L of colostrum harvested 20-60 minutes after calving from the dam or stored refrigerated colostrum from one other cow if the dam’s colostrum was not available. All calves in the study were single births, weighing at least 70 lbs., with a calving ease score of less than or equal to 3 on a scale of 1 to 5. All calves were fed the same commercial milk-based replacer after their colostrum feeding. The results shown in the table below and underline that the 24-hour samples for serum protein and IgG in the calves did not differ between 2-dose CR and colostrum, but were greater than 1-dose CR. The apparent efficiency of absorption (AEA) was similar on all treatments, but much better rates of adequate passive transfer (APT) occurred on the 2-dose and colostrum treatments.

High quality maternal colostrum is still the best option for feeding newborn calves. However, there are times and circumstances when colostrum replacer or supplement products can be valuable tools to have available. When selecting a product to use, it is very important to understand if the product is USDA licensed, what the IgG level is, to follow mixing directions carefully, and how many doses should be fed to deliver the calf a minimum of 100 g of IgG within 4 hours of birth.

Kelly Driver has been involved in the New York dairy industry all her life. In addition to raising dairy calves and replacement heifers, she is the Northeast Territory Manager for Calf-Tel. Feel free to contact her at kellydriver@hampelcorp.com with your calf questions or suggest a topic you would like covered in a future blog.

Sources

Godden, S.M., D.M. Haines, and D. Hagman. (2009a). Improving passive transfer of immunoglobulins in calves. I: dose effect of feeding a commercial colostrum replacer. Journal of Dairy Science, 92:1750-1757.

Kertz, A.F. (2009). Calf colostrum replacer can meet IgG needs. Feedstuffs. September 14, p.12.

Lago, A., M. Socha, A. Geiger, D. Cook, N. Silva-del-Rio, C. Blanc, R. Quesnell, and C. Leonardi. (2018). Efficacy of colostrum replacer versus maternal colostrum on immunological status, health, and growth of preweaned dairy calves. Journal of Dairy Science, 101: 1344-1354.

Penn State Extension Service. (2020, April). Colostrum supplements and replacer. American Dairymen, vol. 45, no. 4: 28-32.

Priestley, D., J.H. Bittar, L. Ibarbia, C.A. Risco, and K.N. Galvao. (2013). Effect of feeding maternal colostrum or plasma-derived or colostrum-derived colostrum replacer on passive transfer of immunity, health, and performance of preweaning heifer calves. Journal of Dairy Science, 96: 3247-3256.

by Cari Reynolds, W.H. Miner Institute

As cooler weather sets in and the leaves begin to turn, we humans start to think about ‘sweater season’ and, perhaps even more importantly, ‘soup season’. The nip in the air invites thoughts of warm, hearty meals, and there are few things more inviting than a steaming bowl of soup on a chilly day. While the health benefits of a warm bowl of soup are anecdotal at best for humans (although homemade chicken noodle soup from one particular restaurant in my home region is my sworn go-to for kicking a cold), research continues to explore the impact of heat-treated colostrum on calf health. In fact, companion articles from Cornell University recently published in the Journal of Dairy Science provide new information on how heat treatment may affect other essential immunological components of colostrum and their contribution to calf development.

Colostrum management on farms is one area where cleanliness and quality are imperative. It is important to give the calf a good foundation for her immune system. High bacterial content in colostrum leads to a decrease in available immunoglobulin G (IgG), which lowers the amount available for absorption in the calf. Gut maturation and development are also supported by other complement components present in colostrum, such as growth factors, cytokines, hormones, enzymes, insulin, and insulin growth factor I (IGF-I). Many of these components and their mechanisms in colostrum have been understudied, but advancements in proteomics are allowing for further exploration of these components and their roles in immune and gut development. While it is well-documented that heat treatment reduces bacterial count and preserves IgG fractions, these two studies aimed to further explore what effects heat treatment may have on these other essential components and subsequent impact on the calf’s health and development.

First-milking colostrum from 11 Holstein cows, of which the average Brix percentage was 27%, were collected on one commercial dairy in New York State. Colostrum from each cow was collected 3x over one day post-parturition, homogenized, and divided into two 4-L (1 gallon) bags for a total of 22 paired batches. One bag was placed on ice for 30 min, then stored at 4°C (39° F) for up to 24 h. The second bag was heat treated at 60°C (140° F) for 60 min immediately after filling, placed on ice for 30 min, then stored at 4° C for up to 24 h. Samples from the raw and heat treated colostrum batches were analyzed for somatic cell count (SCC), bacterial contamination, IgG, IgA, complement components, proteins, insulin, and IGF-I. As exhibited in previous work, the heat treatment considerably improved the hygiene of the colostrum. Average SCC of the 11 raw colostrum samples was 470,000 (range 300,000-1,300,000); heat treatment reduced this count by 207,000 ± 68,000, or 36%, in comparison to their raw counterparts. Heat treatment also reduced bacterial counts by 93% in comparison to raw colostrum.

However, heat treatment reduced IgA (which is crucial to development of mucous membranes) by 8.5% when compared to raw colostrum, and reduced IgG by 6.6%. Heat treatment also decreased insulin by 22%, and IGF-I by 10.2%. A total of 328 distinct complement proteins were identified in the colostrum samples, many of which were decreased by heat treatment. While they may not be found in high concentrations, the presence of these complement components are important to the development of the neonatal immune system. The authors then sought to determine if whether or not a reduction in abundance of these components also translated to a biological impairment, or a reduction in their circulating concentrations.

Twenty-two Holstein calves were enrolled to be fed either the raw (R, n =11) or heat treated (H, n =11) colostrum at 8.5% of their body weight (0.87 and 0.91 gallons, respectively). Colostrum was placed in a 43°C (104° F) water bath for 20 min to warm to feeding temperature, and fed to calves within 1 hour of birth via an esophageal feeder. None of the calves received colostrum from their own dam. Calves were moved to a group pen (20 calves/pen) 8 h after feeding, where free-choice, heat-treated milk was offered ad libitum, and calves were treated similarly for the remainder of the preweaning period. Blood samples were collected from each calf immediately before colostrum feeding, and at 4, 8 and 24 h after feeding. Weaning weights were collected at a targeted 64 d.

Calves in both groups demonstrated successful passive transfer of antibodies, with serum IgG concentrations above 10 mg/mL. Weaning weights and average daily gain did not differ between the R and H groups, nor did the levels of serum IgA and IgG 24 h after feeding, despite the reduction of both by heat treatment. Insulin levels peaked at 4 h, but differed at 8 h as decline in insulin in group H was slower than that of group R. No differences in IGF-I were detected between groups. Insulin and IGF-I concentrations were of particular interest to the researchers due to the observed reductions in the heat-treated colostrum. 663 unique proteins were also identified in serum samples; a large number of these were noted to have changed in abundance between the 0 and 8 h timepoints, suggesting a change in the calf proteome following colostrum feeding. Of those serum proteins that were increased in abundance, 41% were also identified in the colostrum samples, and were classified as those involved in immune response and coagulation. These results suggest that many of these immunological factors are present in colostrum and help contribute to the establishment of the neonate immune system, and that lowered abundance in the heat-treated batches did not translate to diminished uptake or effect.

While more investigation of the calf proteome and the effects of heat treatment on complement components of the immune system is still necessary, this research continues to support the method of heat treatment for preservation of colostrum quality. Enhancing our understanding of these complement components and proteins, as well as their roles in development, will provide more opportunities to optimize calf health through management and nutrition strategies. Bring on the cold weather, and bring on those warm bottles!

Cari Reynolds earned a BS in Biology from the University of Scranton and a Master of Public Health from the University of Massachusetts – Amherst. After several years working in the public health sector, Cari returned to her agricultural interests and she is currently a research intern at W.H. Miner Institute. Cari is a Ph.D. student in Animal Science at the University of Vermont, where her research will focus on management and preventative strategies to mitigate diseases that impact both human and animal health. She can be reached at reynolds@whminer.com.

References

S. Mann, G. Curone, T. L. Chandler, P. Moroni, J. Cha, R. Bhawal, and S. Zhang. 2020. Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-1 concentrations, as well as the colostrum proteome. J. Dairy Sci. 103: 9368-9383.

S. Mann, G. Curone, T. L. Chandler, A. Sipka, J. Cha, R. Bhawal, and S. Zhang. 2020. Heat treatment of bovine colostrum: II. Effects on calf serum immunoglobulin, insulin, and IGF-I concentrations, and the serum proteome. J. Dairy Sci. 103: 9384-9406.