Letter from the Editor

Happy National Dairy Month! This is the month society dedicates to thanking YOU, our dairy farmers, for all your hard work that provides us with wholesome food products. Thank you!

Summer is officially here and the WSU campus in Pullman is fairly quiet. The hustle and bustle of groups of students headed to class is gone, until August. This is the time of year for scientific conferences, research, and preparing for the fall semester. I had the pleasure of attending two conferences so far this summer. The International Committee for Animal Recording (ICAR) Conference was in Montreal this year. Some of the most interesting research I saw focused on using different types of technology to detect the onset of diseases in cattle. This is also an area of research that my lab has been working on lately. I’ll discuss more about this research in my Top Ten Tips article below. The second conference I attended was the International Society for Agricultural Safety & Health Conference, which was held in Fort Collins last week. It was intriguing to learn about the new methods of monitoring on-farm safety and teaching safe practices.

From a research and Extension standpoint, our dairy faculty have multiple projects in the works right now. Dr. Holly Neibergs conducted genomic selection workshops for dairy producers and veterinarians. Dr. Marcos Marcondes is conducting a research trial on calf nutrition, Dr. Martin Maquivar just started a study assessing repeat breeders, and my lab will be installing lasers next month to test their efficacy in deterring birds from the freestall barns. All of us can not wait to share our results with you in upcoming newsletters!

In the meantime, grab a scoop of ice cream and enjoy our June newsletter.

Enjoy!

Amber Adams Progar, amber.adams-progar@wsu.edu

 

 

What’s New in Dairy Science Research?

Callan Lichtenwalter, Ph.D. Student, WSU Department of Animal Sciences

It may not feel like it yet, but summer is here and that means it’s time for another round up of new dairy science research.  Please enjoy the articles I have chosen to write about for the June newsletter.

Importance of Providing Water to Calves [1]

Farmers may not think to provide water to their calves since calves get hydration from milk, and on average in the U.S., calves are not provided water until 17 days of age.  Researchers from New Zealand wanted to understand how providing water to calves receiving different quantities of milk would affect calf feeding consumption and behavior.  Fifty mixed-breed calves were provided with either high milk allowance (10 L/day) with and without water or low milk allowance (5 L/day) with or without water.  As the calves aged, they began to drink more water, and this was more pronounced in calves receiving a high milk allowance.  All calves also ate more hay and calf starter with age, but calves that were provided with water ate more hay than the calves that were not provided with water.  Across the study, there was a small increase in environmental temperature, but this small increase still caused calves to increase their water intake (8% increase for every 1°C (1.8°F) increase).  The results of this study show that providing fresh drinking water to calves can benefit their welfare, particularly on warmer days, and it may contribute to increased consumption of fiber and the development of the rumen.

Finding a Balance with High Concentrate Feeds [2]

High concentrate feeds are important in the dairy industry because they help support the high energetic demands of a lactating cow.  However, when too much concentrate is added to the diet, there can be negative effects on the cow.  A study on Holstein cows from China looked at how a low versus high concentrate diet affected rumen pH, the amount of inflammatory molecules in the blood, and the amount of fat in the milk.  The high concentrate diet fed in the study caused cows to experience sub-acute ruminal acidosis and have higher concentrations of inflammatory molecules in the blood and lower concentrations of fat in the milk than cows on the lower concentrate diet.  From these results we can see that too much concentrate can cause health and welfare issues for the cow and reduce the components in her milk.  If you have concerns about your cows’ diet, contact your nutritionist to see if any adjustments need to be made.

Affects of Different Calf Feeding Methods [3]

Nutrition is extremely important for the growth and development of calves.  Conventional methods suggest providing milk at about 8-10% of calf birthweight to encourage their transition to solid foods.  Researchers from Iran wanted to see if feeding calves using alternative methods would have an impact on their growth or feed intake.  Using 39 Holstein calves, the researchers tested feeding using the conventional method described above, a low milk intake method where milk provided increased until 30 days of age and then decreased until weaning, and a high milk intake method where milk provided increased until 30 days of age and then decreased until weaning.  Calves fed using the high milk intake step-up/step-down method had a greater dry matter intake, starter feed intake, and average daily gain, but were less feed efficient than the calves fed using the other two feeding methods.  If you plan to sell your calves at a few months of age, the high milk step-up/step-down feeding method might work well for you.  Otherwise, the conventional method is probably still your best option, but contact a vet or nutritionist if you have questions or concerns.

[1] Lowe, G.L., M.A. Sutherland, M. Stewart, J.R. Waas, N.R. Cox, and K.E. Schütz. 2022. Effects of provision of drinking water on the behavior and growth rate of group-housed calves with different milk allowances. J. Dairy Sci. 105(5):4449-4460.

[2] Ma, N., J.A. Abaker, G. Wei, H. Chen, X. Shen, and G. Chang. 2022. A high-concentrate diet induces an inflammatory response and oxidative stress and depresses milk fat synthesis in the mammary gland of dairy cows. J. Dairy Sci. 105(6):5493-5505.

[3] Valehi, M.M., G.R. Ghorbani, M. Khorvash, F. Hashemzadeh, H. Rafiee, and J.K. Drackley. 2022. Performance, structural growth, and digestibility by Holstein calves fed different amounts of milk through step-up/step-down or conventional methods. J. Dairy Sci. 105(5):3988-3996.

 

Amber’s Top Ten Tips: Using thermography on dairies

Amber Adams Progar, Dairy Management Specialist, WSU Department of Animal Sciences

Summer is here. Are you ready for the heat? Are your cows ready for the heat? As we know, heat stress has a multitude of negative effects on cattle well-being. Our ability to detect heat stress, as well as other ailments, early is essential for a positive prognosis for our cattle. One method to detect heat stress in cattle is to use thermal imaging to measure eye temperatures in cows. Thermography also shows potential in helping us identify cows with mastitis, foot issues, septic arthritis, and even cows in heat. Below are summaries of studies that tested  using thermography on dairies:

  1. Eye and rectal temperatures

Eye temperatures from thermal images and rectal temperatures in 113 calves were positively correlated, indicating that thermal imaging of eyes could help producers identify calves with a fever (Cossa et al., 2021).

  1. Heat stress identified by eye temperature

Forty cows exposed to mild – severe heat stress conditions displayed increased respiration rates and core body temperatures, as expected. Eye temperatures recorded with thermal imaging showed that left eye temperature readings had better repeatability than right eye readings. The lacrimal sac part of the eye was most closely correlated with the respiration rates and core body temperatures (Shu et al., 2022).

  1. Thermography does not detect feed efficiency

Thermal images of the cheek, right rib, muzzle, left flank, front, front limb, and hind limb were recorded in high-efficiency and low-efficiency cows, but no difference in temperatures was detected between the two groups of cows (Lombardi et al., 2022).

  1. Pasture access does not affect eye temperature

Average eye temperature, as recorded by thermal imaging, was not affected by housing in one study. Twenty-nine cows housed either indoors full-time or with overnight access to pasture did not differ in their eye temperatures (Crump et al., 2022). Eye temperatures tend to be higher when cows experience chronic stress.

  1. Calves with septic arthritis

Eleven calves with septic arthritis had higher skin temperatures, as recorded by thermography, in the areas of their affected joints (Arican et al., 2020).

  1. Detecting estrus

Muzzle and vulva temperatures were recorded via thermal imaging in 10 cows during different stages of estrus. Muzzle temperatures were 8% higher during standing heat than non-estrus. Vulva temperatures were 10% higher during standing heat than non-estrus (Tiwan et al., 2021).

  1. Udder temperature and SCC

Thermal images of all quarters of udders for 28 cows were compared to somatic cell counts. The front udder quarters were the most correlated with somatic cell counts (Machado et al., 2021).

  1. Mastitis detection

Udder surface temperatures for 105 cows were recorded using thermal imaging. Healthy quarters were 90.3 – 90.7°F and quarters with intramammary infections were 91.8 – 92.7 °F (Velasco-Bolaños et al., 2021).

  1. Locomotion score and foot temperature

Over 200 cows in New Zealand were observed for locomotion scoring and thermal images of their hind feet were recorded. For every one-unit increase in locomotion score, mean foot temperature increased by 0.944 degrees (Werema et al., 2021).

  1. Onset of digital dermatitis

My former graduate student conducted a study during the summer of 2020 that aimed to use thermal imaging to detect the onset of digital dermatitis. The intent was to identify cows developing digital dermatitis sooner so we could provide treatment sooner and, ultimately, improve the animal’s prognosis. We found that foot temperature increased by 73% from 16 days prior to diagnosis to the day of diagnosis (Magaña, 2021).

 

Thanks for reading our June newsletter!

We’ll see you in September for our next edition!