WSU ag senior paper highlights, fall 2023

The relationship between Angus and Santa Gertrudis sired steer calves and Anabolic Implant Protocol relative to steer feeding behavior in the feedlot

By Sarah Bayles (Advisor: Dr. Kara Thornton-Kurth)


Beef cattle production faces challenges such as changing climate, limited water, and fewer resources making it essential to increase production with fewer inputs in order to have a sustainable food supply. Anabolic implants are commonly used in beef cattle to improve feed efficiency and growth in the feedlot setting in both bos Taurus beef cattle and bos Indicus. The Santa Gertrudis breed is 3/8 Brahman and 5/8 Shorthorn and developed to adapt well to hot climates and have rapid growth. Emerging research suggests that different cattle breed types respond differently to anabolic implants. The purpose of this research was to determine the effects of different anabolic implant protocols on feedlot performance in feedlot steers of two different breed types. Sixty steers were stratified by weight and breed in a 2×3 factorial design examining two different breeds: Angus or Santa Gertrudis-influenced, and three implant strategies: no implant, a medium-intensity implant protocol, or a high-intensity implant protocol. Steers were stratified by weight into pens equipped with Vytelle® bunks to collect feeding behavior data. Weight, chute score, exit velocity, serum, rectal temperature, hip height, and 12th rib fat thickness were collected approximately every 28 days. Carcass characteristic data was provided by a commercial harvest facility (Hyrum, UT, USA). Overall, both breed type and anabolic implant protocol influence feeding behavior, feedlot performance, and carcass quality of beef steers. This information will help us to better understand how anabolic implants impact beef steers and could further improve sustainability in the United States beef industry as the climate changes and resources become limited.


In conclusion, it is seen that both breed type and anabolic implant protocol influence feed intake and feeding behavior of beef steers. Additional breed × treatment interactions were found and are discussed in more depth in the referenced article.15 This information will help us to better understand how anabolic implants impact beef steers and could further improve sustainability while optimizing performance and economic return in the United States beef industry as the climate changes and resources become limited.

Rinderpest rights and wrongs: Disease control lessons for the small animal practitioner

By Meagan Soehn (Advisor: Dr. Chrissy Eckstrand)


Rinderpest was the first and only veterinary disease to achieve global eradication. The virus’ lack of carrier state, the development of an efficacious vaccine, and the globally perceived loss of this disease allowed for a coordinated, well-funded, and ultimately successful campaign.

In contrast, canine parvovirus (CPV) causes a highly fatal disease that has persisted despite attempted control efforts. Biologically, CPV is a good candidate for eradication, lacking prolonged carrier states and having an efficacious vaccine. However, immunization failures remain a large problem, and many of these failures are due to lack of resources or owner compliance. To help devise a better control strategy, inspiration can be taken from Rinderpest’s success story. This includes ensuring proper resource allocation, education of owners on the importance of control, and utilizing local efforts tailored to specific communities.


In June of 2011 the world celebrated the first animal disease to be eradicated, and every day since people have wondered which disease is next. While aiming for eradication is a noble goal, and for many diseases may be achievable, I don’t think this was the lesson we were meant to learn. This global triumph merely gave us a crash course in how to look at disease. One must first understand it both biologically and in the ways it impacts society. Then they can begin to control it. The greatest tools are not just vaccines, tests, or other scientific advancements, rather true control requires communication, education, and advocation for the animals, their owners, and all those impacted in their community.

Common causes of abortion in beef cattle in the Southwest Region of the United States

By Jordan Woodbury (Advisor: Dr. Michela Ciccarelli)


Reproductive losses continue to have a major economic impact on the beef cattle industry, abortion being one of the primary causes. There are various etiologies of abortion that can range from viral, bacterial, protozoal, and fungal infections to toxins, nutritional, metabolic, and physical insults. In only ~ 50% of abortion cases, the organisms or causes of abortion are identified, making the problem much more difficult to address. By becoming more familiar with the common types of abortion in a specific region, producers and veterinarians are better able to identify the cause of abortion and develop a plan to prevent it from occurring. This will allow producers to get a better idea of what to look for when it comes to abortion and how to prevent it from occurring. Within this paper, some of the most common causes of abortion recognized in beef cattle in the southwest region of the United States will be further defined and discussed.


It can be concluded that bovine abortions are a primary source of major economic loss within the cattle industry. There are various infectious and non-infectious causes that can lead to abortion, therefore it is essential that producers are educated about the many causes of abortion in the hopes to prevent them from occurring in the first place. By being aware of the symptoms, recognizing toxic plants, vaccinating animals, removing the cause, and treating early on, it is likely to reduce the risk of abortion. Having a good working relationship with a veterinarian is also very helpful as they can be a useful tool in helping producers address the issue and help develop a plan on how to move forward. There are various studies that are still being conducted, with the goal to further pinpoint common causes of abortion and how to manage them. At the end of the day, the veterinarian’s role is to work as a team with the rancher to produce the highest quality product possible.

Assessing the relationship between pulmonary lobar consolidation and bacterial prevalence in the upper respiratory tract of Holstein dairy calves

By Katherine Trepanier (Advisor: Dr. Craig McConnel)


Bovine Respiratory Disease (BRD) is a major cause of morbidity and mortality in preweaned dairy calves. This leads to major economic losses for the dairy industry as well as raising concerns about health and welfare. With increasing concerns about antibiotic resistance and more regulation around the use of antibiotics it is imperative for producers to be able to identify disease accurately so they can treat effectively. Using thoracic ultrasound is a promising way for producers to better identify calves that have lobar consolidation and need to be treated or culled which helps to improve animal welfare. Research around thoracic ultrasound has shown that it could be an effective way to diagnose and guide treatment decisions. This paper demonstrates the association between nasal swab bacterial prevalence and pulmonary lobar consolidation in Holstein dairy calves.


This research shows the information that can be gained from performing thoracic ultrasounds on dairy calves, which can be interpreted and used to help guide management decisions. Despite the high bacterial prevalence especially of Mycoplasma bovis on one farm we cannot conclude that there is any association with lobar consolidation, this is because of the high prevalence of Mycoplasma bovis as identified by PCR done on the nasal swabs. Future research could look at bacterial presence in lung lobe lesions to see if the high prevalence is associated with increased lobar consolidation. This data could then be used to offer more specific recommendations to the producer on what to vaccinate against. This research shows the importance of epidemiology for advising producers on management decisions. To increase animal welfare and decrease the use of antibiotics more research should be done on thoracic ultrasonography to better understand its abilities to help producers make management decisions.