Kentucky Dairy Notes. September Key Connections in Calf Management By: Karmella Dolecheck and Jeffrey Bewley

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1 Kentucky Dairy Notes September 2017 Key Connections in Calf Management By: Karmella Dolecheck and Jeffrey Bewley What can you do to improve calf health, growth, and welfare? The National Animal Health Monitoring Service conducted a survey in 2014 and 2015 to try and answer that question. One hundred and four farms from 13 states provided data from a total of 2,545 heifer calves. Each calf was followed from birth until weaning. Based on those calves performance, the following relationships were found for disease incidence, colostrum management, and average daily gain. Knowing these relationships can help identify both specific calves that may be at risk and general farm management practices that could improve calf productivity. The chance of getting a disease was higher: -In calves with lower birth weights -In calves with lower serum IgG (IgG concentration in the blood of calves reflects the amount of antibodies absorbed from colostrum.) -In calves without natural ventilation -When temperature humidity index was higher The chance of contracting cryptosporidiosis was greater: -On large farms -In younger calves -In higher temperature humidity index conditions The chance of contracting giardia (an infection of the intestine known to cause diarrhea) was greater: -On small farms -In older calves -In calves experiencing a lower average daily gain -In calves that had experienced cryptosporidiosis previously -In higher temperature humidity index conditions -If colostrum was heat treated (Heat treatment or pasteurization of colostrum decreases bacteria counts. Studies have shown reduced absorption of antibodies with high bacterial counts in colostrum.) -If colostrum came from a parity 1 cow (because production was lower, resulting in a higher concentration of antibodies) -If time from birth to feeding of colostrum was short (Ideally, colostrum should be fed within 6 hours of birth.) -If volume of colostrum fed was greater (for every 1 L of colostrum fed in the first 24 h after birth, serum IgG increased 0.56 g/l) -If IgG levels in the colostrum were higher (for every 10 g/l increase in colostrum IgG, serum IgG increased 1.1. g/l) Average daily gain was higher: -In calves born from cows in parity 2 and greater -In calves born as singles as opposed to twins -In calves that did not experience cryptosporidiosis or giardiasis -In calves fed a greater amount of protein in their liquid diet per day (every 2.2 lb of protein fed per day resulted in 0.04 lb/day of gain) -In calves that had no diseases present versus those that had one or more disease -In calves bedded with straw, hay, shavings, or some combination of these as compared to calves bedded with sand or no bedding -When the temperature humidity index was less than 50 Information in this article was presented at the Joint Annual Meeting in Salt Lake City, July 19-23, by researchers from the National Animal Health Monitoring System and Colorado State University. Passive transfer of colostral antibodies was more successful: -In the Western US compared to the Eastern US

2 What do I need to consider before investing in a robotic milking system? By: Derek Nolan and Jeffrey Bewley More and more dairy producers are considering investing in automatic milking systems (AMS) around the United States. Producers all around the world have been adopting robotic milkers to allow for more freedom in their daily lives and to replace labor. No longer is the producer committed to two or three milkings each day. While their day may be less structured, some changes need to be considered when it comes to the day-to-day management of the dairy herd. Before Installation Before installation of the AMS, Jack Rodenburg, DairyLogix, stresses management practices that need to be considered. The first is the housing type. Two different types of systems are common with a robotic milker. The first is a free flow system. In a free flow system, cows are allowed to roam freely around the barn with unlimited access to the AMS, feed bunk, and housing. On the other hand, guided systems force the cow to enter one area before another. The most common is for the cow to enter the AMS before going to the feed bunk. This provides an incentive for the cow to milk. Neither system is perfect. In a free flow system, cows average two milkings per day compared to 2.6 in a guided system. However, cows in a free system average 12 meals a day compared to only 3.9 in a guided system. The number of fetch cows, cows that do not come to the AMS voluntarily, is also affected by the system type with an average of over 16% of cows needing to be fetched in a free system, with less than 9% in a guided system. In either system, by considering space during the building process, the producer can decrease fetching. Limited space, both for the cow and around the AMS, can increase the number of fetch cows. An AMS system can handle around 60 cows. More cows per robot than that leads to more fetch cows and lower milking frequency. Free space in front of the robot is critical. If space is tight, timid cows will not come up to milk as often, as dominant cows push them out. Anything that attracts cows, such as brushes, needs to be placed at the opposite end of the barn, to relieve traffic to the AMS. If a barn contains multiple robots, robot orientation should be the same for all units. Cows are habitual creatures and if most of the herd decides they like one robot over the other it will build traffic and lower milking frequency. Placing robots in the same orientation also relieves exit and entry traffic from the robots. Easy traffic flow makes for easy fetching. Besides easy fetching, other aspects of the barn need to be considered to make management less laborious. When building the barn, Rodenberg stresses, try to make every job a one-man job. Consider how the barn design will affect scraping, cow management, or herd health and reproductive checks. Herd Health and Reproduction Dr. Stephen LeBlanc, Ontario Veterinary College, suggests there has been some concern with potential issues of unit attachment and teat cleaning with an AMS. Farms that follow the NMC guidelines for milk prep are consistently better at teat prep than a robot. A cow entering the AMS with clean teats is more important than it would be in a parlor because the robot follows the same procedures every time where a human will spend extra time with a dirty cow. Robotic milking herds tend to have a higher SCC than conventional herds. Herds with a SCC between 200,000 and 250,000 tend to increase where herds over 300,000 tend to decrease after adoption. One reason for the increase may be due to the increase in milk production that comes with adoption of the AMS. LeBlanc points out other herd health factors do not see much of a change from conventional to an AMS. Both reproductive success and metabolic health tend to be no better or worse after the adoption of robotic milkers.

3 What do I need to consider before investing in a robotic milking system? Continued... Even though change in herd health is minimal to nonexistent, the potential an AMS system has to monitor the health of individual cows can be a major benefit. An AMS can provide 120 pieces of information per cow per day. Data provided is consistent and objective allowing the producer to track changes in the cows data output. As more research is completed on the data and patterns it creates, producers will be able to set alerts when cows go outside of their daily routine. Nutrition Dr. Alex Bach, Institut de Recerca i Tecnologia Agroalimentàries, suggests an AMS gives the producer the opportunity to structure more to a cow s individual needs compared to a complete TMR. Concentrate provided by the robot is used to entice cows to enter the AMS. However, a large amount of concentrate provided by the robot does not make it more enticing for milking. If too much is provided the cow will not eat all of it leading to more cleanout by the producer. Two to three lbs. of concentrate should be provided per milking. A TMR balanced for one cow leads to an unbalanced ration for another. An AMS can allow for selective concentrate feeding but a producer can run into the same problem of a batch TMR by feeding only one type of pellet. Bach suggests by investing in multiple concentrate boxes, a balanced concentrate can be offered to meet individual cow needs. Economic Investment Adoption in an AMS by most producers is for a lifestyle change and to replace labor. Producers that have invested in a robot see a 10% to 29% reduction in labor. The value of an AMS is just shy of $200,000. Dr. Jim Salfer, University of Minnesota, suggests the cost of labor is a major variable in determining the value of the AMS. When number crunching, the producer must consider wage inflation. Labor wages will change while a robot is going to stay constant. For every $1 increase in the annual labor the profitability of the robot increases by $4 and for every additional year of life of the robot the value increases by approximately $16,000. Salfer advises the other variable that plays a large role in the profitability of an AMS is cow throughput and milk production per robot. A robot can be more profitable than an underutilized parlor, which is common for the small dairies that adopt them. After adoption, producers should cull cows that do not adapt to the robot or have long milk out times. This will allow the AMS to run more efficiently and have a greater throughput. Final Take Home Message Perhaps the biggest consideration is how labor use will change. None of the other considerations will be beneficial without the change of labor. Milking labor should now be management labor. Producers should now spend extra time managing their herd, from retrieving fetch cows and fresh cows to examining alerts from the data provided by the AMS. The robot allows producers to manage the cow s individual needs. In order to reap all the benefits of the AMS, the producer must shift from manual labor to management labor. Dare to Dairy When: October 21, 2017 Where: University of Kentucky Coldstream Dairy Cost: $15 per person Registration Deadline: October 2, 2017 Open to 4-H and FFA members who would like to learn more about the science behind milk production. 4-H members may receive 3 livestock educational hours for this event. 4-H volunteer leaders may also receive 3 hours towards their continuing education hours (Please bring your completed form to be signed).

4 Managing Cows: How Nutrition Impacts Lifelong Health By: Amanda Lee and Jeffrey Bewley Proper nutrition is crucial to the development of calves, heifers, and cows. Researchers from around the world are exploring novel options to promote healthy growth and development in heifers, reduce transition cow diseases, and provide proper nutrition for pasture animals. With an increased emphasis on cow longevity and overall health, exploring new options for nutrition can help producers to better understand how to effectively feed their animals. Researchers from South Dakota State University reported that high forage, low concentrate diets might have low feed efficiency because of poorly digestible fiber. Thus, alternative nutritional sources or feeding protocols, such as limit feeding, are needed to provide heifers with quality, highly digestible sources of fiber. In limit feeding, producers feed a set amount of nutrient dense diet and ad libitum hay to improve feed efficiency and decrease the cost of growing feed. The objective of the study was to compare the effects of limit feeding with distiller grain versus ground corn and soybean product mix when fed with ad libitum grass hay. A 16-week feed trial exposed 24 cows to one of two treatments: distillers grain concentrate mix or corn and soybean product concentrate mix. Because distiller s dried grains had a greater fat concentration, the diet intake composition had a significantly higher NDF and ether extract in heifers fed distillers dried grain. However, there was no difference in average daily gain, DMI, BW, or frame growth between the two groups of cows. Looking at rumen fermentation, cows fed distillers dried grains had greater propionate and butyrate than cows fed ground corn and soybeans. However, when considering total tract digestibility, there were no differences in dry matter, organic matter, crude protein, or NDF between the diets. Overall, the study suggests that limit feeding with distillers dried grain as the primary concentrate in addition to ad libitum grass hay maintains the same level of growth performance, energy status, dry matter intake, and nutrient digestibility. Take home message: When considering how and what to feed heifers, all aspects of the diet must be analyzed. Although no perfect feed exists, a ration must be balanced to provide adequate NDF, CP, and energy. Okara is the residue extracted from soybeans used to make soy and tofu products. Frequently, okara is considered a waste product and it can be highly susceptible to bacterial growth if not properly dried. The crude protein content ranges from 25.5 to 37.5 % and 45.5 to 58.6 % total carbohydrates. In a previous study, up to 12 % okara as dry matter did not affect dairy cows milk production or digestibility. The objective of the current study conducted at the University of New Hampshire was to determine how replacing soybean meal with okara meal changes milk production, milk composition, and nutrient digestibility in dairy cows. Twenty cows were exposed to a soybean based or okara based diet for 21 days. Researchers found no difference in feed intake, feed efficiency, energy corrected milk, 4% fat corrected milk, and milk yield between the groups. However, cows fed okara meal had significantly lower true protein percent. In considering change in digestibility, no difference was seen between okara and soybean meal in dry matter intake and digestibility, organic matter intake and digestibility, or NDF intake or digestibility, although CP intake was significantly lower in cows fed soybean meal. Take home message: Overall, okara meal can potentially replace up to 8% of soybean meal when fed on a dry matter basis without affecting milk yield or dry matter intake.

5 Managing Cows: How Nutrition Impacts Lifelong Health continued... Transition cows require additional management to prevent ketosis and hypocalcemia, and researchers in Canada are trying to determine when and how a producer might intervene to prevent disease incidence. Flax oil may serve to aid in the energy balance during early lactation of high producing dairy cows. Flax oil is approximately 41% fat and 20% protein and has been shown to reduce fatty liver disease and increase fertility. However, researchers are unsure which component contributes these benefits. Thus, researchers tested two groups of cows by infusing 0.6 lbs of flax oil into the abomasum daily. One group was also supplemented with an additional 15% flax meal in the dry matter. Blood, urine, liver, and mammary gland biopsies were collected from day 7 to 49 in milk. No difference was seen between the two groups in oxidative liver damage, but greater DNA damage was seen in the group supplemented with flax oil in both mammary gland and liver. Overall, flax meal did not reduce the risk of disease in fresh cows. Take home message: Flax meal must be analyzed further to determine if there is potential benefit in feeding to the fresh cows. Because Irish dairies typically keep cows on pasture 220 days per year, seasonal calving must occur to prevent grass shortages. With the abolishment of the quota system in 2015, producers are no longer limited by production, but continue to face challenges in land and feed availability. Because there is a high cost associated with cereal growth, there has been increased emphasis on replacing cereals with other byproducts such as palm kernel, soya hulls and distillers grain. The objective of the study was to determine the effects of byproduct inclusion on body weight, BCS, and DMI. Cows were separated into four groups: cows fed 6.6lbs concentrate by-product at 35% inclusion level, 13.2 lbs by-product fed at 35% inclusion level, 6.6 lbs concentration by-product at 95% inclusion level, and 13.2 lbs by-product fed at 95% inclusion level. By feeding 13.2 lbs rather than 6.6 lbs of concentrate, cows tended to produce 4.3 lbs more of milk (or 1.3 lbs more per lb of concentrate above 6.6 lbs). No differences were seen in milk solids or protein produced or pasture DMI intake. Kilograms of milk fat per cow per day were significantly greater in cows fed 13.2 lbs of concentrate than 6.6 lbs of concentrate. Although rumen ph was significantly lower in cows consuming the higher concentrate, the cows still had normal rumen ph and were not at a higher risk for SARA. Take home message: Cows can be fed up to 95% concentrate with byproducts without changes in DMI, milk production and composition, BCS and BW. Although feeding 13.2 lbs of concentrates resulted in higher milk production and fat concentration, it is currently not economical to feed such high concentrate levels at current milk prices. This research was presented at the American Dairy Science Association and American Society of Animal Science Joint Annual Meeting in Salt Lake City, Utah on 20 July 2016.

6 Water Needs for the Dairy Herd By: Hannah Himmelmann and Donna M. Amaral-Phillips, PhD Most people know that water is required for survival. What people tend to forget is just how important water is. In fact, water is the most important nutrient for the milking dairy cow. Water intake is critical in order to obtain maximum production from dairy cows. Without proper water intake, productivity will decrease, which can lead to economic loss. Water Amount The amount of water dairy cows consume is vital. Cows should consume between 30 and 50 gallons per day. This is over 415 pounds of water per day. Why do they need this much water? It takes between 4 and 4.5 pounds of water to produce 1 pound of milk. Milk consists of 87% water. Insufficient water intake will result in decreased milk yield. Dairy cows rely on saliva and other fluids to assist in the digestion of feedstuffs. This increased need for saliva requires water. If water intake decreases, the digestion of the feed decreases. A decrease in water intake results in decreased feed intake. Decreased feed intake can have detrimental effects on dairy cows. Cows get their energy from feed which is needed for producing milk. Managing the Dairy Herd s Water Supply Managing water on a per cow basis in a dairy herd can be quite difficult. For this reason, it is best to make decisions that will benefit the herd as a whole. Cows must have access to water when they are in the barn. The water trough should be centrally located or located where all cows in a group can access it easily. Placing the water trough close to the feed bunk allows cows to drink after eating. Cows tend to drink the most after eating and being milked. There also should be plenty of space for multiple cows to drink at once. Each cow should have 3 to 5 inches of water space available to them. The height of the trough should be 2 to 3 feet. The fill rate of the waterer should be a little over 2.5 gallons per minute. If the herd is split into multiple groups, each group should contain its own water trough. One water trough should be present for every 20 cows. The number of cows in the barn will determine the number of waterers needed. The water trough also needs to hold no less than 5 gallons at a time. The trough that holds the water should be clean and provide fresh water at all times. An automatic waterer ensures cows will have the correct amount of water offered to them at all times. However, automatic waterers and float valves still must be cleaned at least once a week. In conclusion, water is the most important nutrient a dairy cow receives. In order to achieve maximum productivity, cows need to obtain the required amount of water each day. While it is hard to manage water intake per cow, managing the entire herd s water intake is simple and effective.