By Bailey Bailey (Advisor: Dr. Ramanathan Kasimanickam)
Summary: This paper serves as a comprehensive overview of Neonatal Maladjustment Syndrome (NMS) in cattle. There are several other terms that are recognized as NMS andthe syndrome is not unique to cattle. This paper should provide a better understanding of the clinical signs that the syndrome encompasses, thoughts on etiology, major risk factors, strategies for treatment, and preventative measures. Given its impact on calf survival and an operation’s profitability, economics was considered. While elements of etiology are not fully understood, there is value in researching how one manages these cases. It is the author’s intent to equip the novice reader with enough of a foundation to confidently navigate these cases. The seasoned practitioner can also utilize this as a compilation of current thoughts about NMS. Due to the multifactorial nature of this syndrome, and the varying clinical presentation of the calves, their management can be complex and frustrating. However, efforts to provide these neonates with care can be utilized in the treatment of several neonatal conditions. It is important to note that this paper does not attempt to cover every cause of NMS but instead highlights the most common etiologies. Because of the overwhelming number of risk factors, it was attempted to consolidate this information into one source. As the author, my motivation stems from my commitment to becoming an exceptional bovine practitioner and a desire to learn more about bovid neonatal care. To compile this information, I have referenced several journals that demonstrate current and past NMS research. Additionally, materials presented by educators at Washington State University’s College of Veterinary Medicine were reviewed before the writing process.
Conclusions: This paper provides a broad overview of current understanding of NMS in calves. What the syndrome encompasses has been defined and the proposed etiology and risk factors were discussed. Additionally, therapeutic and preventative measures were described. Hopefully, the reader walks away with a better understanding of NMS and its impact on producers. Provided this information, hopefully cases of NMS will be less troublesome for the clinician to navigate. Because the syndrome can be linked to several etiologies, no two cases are likely to present or respond to management in the same way. Thankfully efforts to provide supportive care can be utilized in more than just NMS patients; therefore, this section of the paper served as a good refresher on neonatal resuscitation. It is important to note that even in the face of excellent supportive care, prognosis can be poor. For this reason, prevention was discussed in detail, considering it is the best option for combatting NMS. If anything, this paper should prove to the reader that several aspects of management must be considered in outbreak scenarios and getting to the bottom of the etiology requires a significant amount of investigation. Ultimately, there is still a lot we do not know about this syndrome, but given its prevalence, we can presume it will continue to be researched.
By Chance Marsh Advisor (Dr. Ramanathan Kasimanickam)
Summary: The postpartum period is a critical time for dairy cattle, marked by profound physiological changes that increase susceptibility to a variety of metabolic and reproductive disorders. Among the most prevalent diseases during this period are ketosis, hypocalcemia, and uterine diseases including metritis, purulent vaginal discharge (PVD), and subclinical endometritis (SCE). This review provides an in-depth discussion of the pathophysiology, diagnosis, treatment, and prevention of these conditions. Ketosis stems from negative energy balance and excessive fat mobilization, leading to ketone body accumulation. Hypocalcemia arises from insufficient calcium mobilization and is influenced by metabolic alkalosis and hypomagnesemia. Uterine diseases develop from bacterial contamination during parturition and dysregulation of uterine immunity. Effective management involves timely diagnosis, evidence-based therapeutic interventions, and nutritional and environmental strategies aimed at prevention. Understanding the complex interplay of metabolic and immune mechanisms during the postpartum period is essential to improving herd health, reproductive performance, and overall productivity in dairy operations.
Conclusions: Postpartum diseases in dairy cattle represent a convergence of metabolic imbalance, immune dysfunction, and environmental challenges during a period of intense physiological demand. Ketosis exemplifies the consequences of negative energy balance and excessive fat mobilization, while hypocalcemia highlights the critical role of calcium homeostasis and the complexities introduced by metabolic alkalosis and mineral imbalances. Uterine diseases, including metritis, PVD, and cytological endometritis, underscore the importance of microbial regulation and immune competence in the postpartum reproductive tract. Effective management hinges on early detection, targeted treatment, and proactive prevention, particularly through nutritional planning, body condition scoring, and microbial control. While current therapies show promise, variability in treatment responses, particularly in uterine diseases, indicates a pressing need for further research. Continued efforts to understand the multifactorial nature of postpartum disease will enhance health outcomes, reduce losses, and improve sustainability in dairy production systems.
By Kaatje Fisk (Advisor: Dr. Heloisa Rutigliano)
Summary: In vitro 2-dimensional trophoblast cell cultures systems are limited by their inability to accurately mimic the complexity of tissue structure and physiology of in vivo placentation. Three-dimensional (3D) long-term cultures have the potential to represent the in vivo microenvironment of placental tissue more accurately. This study aimed to characterize the morphology, gene expression and protein expression of cells from a long-term 3D bovine trophoblast culture. Cellular viability and proliferation assay results show proliferation in all culture groups with cell numbers less than 10,000 at the beginning of the assay. Gene expression was assessed using qRT-PCR to compare long-term 3D trophoblast cultures and day 40 fresh placental tissue. Expression of trophoblast specific genes and transcription factors were evaluated. Gene expression results show that the 3D cell culture groups express placenta specific genes, and that expression of these genes was maintained throughout the duration of time in culture. The presence of Placental Alkaline Phosphatase (PLAP) was assessed using a sandwich ELISA. PLAP was detected in all 3D culture groups at variable concentrations. Histologic analysis of 6-month 3D cell culture shows presence of binucleate cells which indicates differentiation of the trophoblast cells in culture. Further characterization of this 3D model is needed to better understand if it could be a useful tool to study fetal-maternal interactions in cattle. Future characterization assays will include Western Blot and immunohistochemistry to assess protein expression and physical distribution of placental proteins in the 3D cell culture model.
Conclusions: Cell viability and proliferation assay results show cellular proliferation over the 24-hour period in all culture groups with seeding densities less than 10,000 cells per well. Culture groups starting with seeding densities greater than 10,000 cells per well show a decline in cell number over the course of the 48-hour assay. This decline in cell number can be attributed to the high seeding density and rapid utilization of culture media components by viable cells in the 24 hours of incubation prior to addition of the assay reagents and absorption measurements. In future assays cell seeding density needs to be controlled for. Using a hemocytometer, cell counts for each culture should be established prior to plating to ensure that each well contains less than 1000 cells. This will prevent complete consumption of available media components and allow cell proliferation to be accurately measured. Programmed death ligand 1 (PD-L1) is a cell surface protein expressed by trophoblast cells and modulates the placental immune environment during gestation. This protein facilitates the transition of M1 to M2 macrophages promoting an anti- inflammatory environment which is a crucial step in the maintenance of pregnancy in humans. Expression of this surface protein is maintained in 3D cultures as we would expect it to be expressed in in vivo placental tissue. Prostaglandin-endoperoxide synthase 2 (PTGS2) is an important cyclooxygenase that is expressed by the trophectoderm of the conceptus in early pregnancy, specifically elongation and implantation. PTGS2 plays a crucial role in regulating the synthesis of prostaglandins during early pregnancy.13 This enzyme is expressed in 3D cultures and overtime in culture we see a reduction in expression. Bovine prolactin related protein VII (bPRP-VII) is a protein expressed in trophoblast cells that is involved in development of syncytiotrophoblast cells, also known as binucleate cells. The expression of this gene in the 3D cultures indicates the potential for these cells to differentiate while in culture to form binucleate cells. These cells are unique to ruminant placentas and are a key feature of the placental microenvironment. PAGs 11 and 12 are expressed in mononucleate trophoblasts and their function is still being investigated, but they are believed to play a role in placental adhesion to the endometrium. Evidence of trophoblast specific gene expression in 3D long-term cultures show potential for this cell culture model to reflect the placental microenvironment. Further quantification and comparison to a 2D cell culture system is indicated in future studies to determine if this model could be a useful tool to study bovine placentation. Placental alkaline phosphatase concentrations were detected in all 3D culture groups at variable levels. There were no significant changes in protein concentrations between 6-month and 12-month 3D trophoblast cell cultures. Histologic analysis of 6-month 3D cell culture shows the presence of binucleate cells which indicates differentiation of the trophoblast cells in culture. In vivo, trophoblast binucleate cells form on day 19-20 of gestation. This trophoblast tissue was harvested on day 17 of gestation and should not have differentiated binucleate cells. Presence of binucleate cells indicate that the cells continued to differentiate while in culture. These results show that the 3D trophoblast cell culture model is morphologically similar to placental tissue and has the potential to represent the in vivo placental microenvironment. The 12-month culture group morphology results revealed 3D trophoblast spheroids comprised of multiple cells. This confirms cell-cell interactions form in the 3D culture system that recapitulate the in-vivo microenvironment more accurately than a classic 2D cell culture model. Further characterization of this 3D model is needed to better understand if it could be a useful tool to study fetal-maternal interactions in cattle. Future characterization assays will include immunohistochemistry to assess protein expression and physical distribution of placental proteins in the 3D cell culture model. The scope of this study was limited due to the study timeline. My contribution to this work began 12 months following the establishment of the 3D cell culture systems, and therefore, my ability to acquire control groups to compare cell culture systems to freshly harvested trophoblast cells and 2D cell culture systems was restricted. Future characterization of this 3D system should be compared to trophoblast cells that are freshly harvested at several time points in gestation and compared to a 2D trophoblast culture system cultured in stock DMEM/F12 culture media. The results from this experiment indicate that these trophoblast cells maintain characteristics of in vivo trophoblast cells but quantification of protein expression, and PLAP concentrations among these control groups is necessary to better understand the accuracy of this culture system compared to the in vivo microenvironment of bovine trophoblasts.
By Mirella Ramirez (Advisor: Dr. Craig McConnel)
Summary: Listeria monocytogenes (L. monocytogenes) is a significant foodborne pathogen that affects both animals and humans. This pathogen is found worldwide, in various environments, including soil, water, and animal feces. It creates a persistent risk in food production, especially in developing countries with inadequate food safety practices. Factors contributing to the prevalence of L. monocytogenes include inadequate sanitation, a lack of regulatory oversight, and insufficient education for personnel involved in food handling and preparation. Although developing countries have limited resources to fund organizations that can prevent outbreaks of L. monocytogenes, outbreaks also occur in developed nations, where manufacturing processes and refrigeration can create favorable conditions for this bacterium to thrive. In terms of pathogenesis, L. monocytogenes can infect animals through ingestion, inhalation, or direct contact. L. monocytogenes remarkable adaptability enables it to survive in virtually every environmental condition contributing to its status as a global public health concern. If food processing and handling are not done properly, L. monocytogenes can be harbored in food products such as meats, dairy, and ready-to-eat items. Organizations in developed countries are working to mitigate risks through food safety regulations and response strategies; however, ongoing vigilance is necessary to prevent outbreaks of listeriosis.
Conclusions: L. monocytogenes is a highly adaptable bacterium that causes disease in humans and animals. It is important to prevent L. monocytogenes from infecting animals that are then processed for human consumption. Veterinarians have a responsibility to help prevent L. monocytogenes from infecting animals at the farm and food processing level. By recognizing the clinical signs that distinguish L. monocytogenes from other known foodborne diseases or neurological diseases, and using the diagnostic tools available to get a definitive diagnosis to treat animals accordingly. Veterinarians also play a role in training animal handlers to identify L. monocytogenes in early stages of disease, how to properly dispose of contaminated animal secretions, and how to prevent the spread of L. monocytogenes to humans or other animals. Although the elimination of L. monocytogenes may not be possible, it remains preventable through simple hygiene protocols implemented at the food processing level and through the development of new technologies created each year. Further investigations are needed to verify whether the new technologies pose any potential harm to humans who consume these animal products.
By Larell Bermudez-Koch (Advisor: Dr. Craig McConnel)
Summary: Developing a diagnostic testing strategy for Johne’s disease (Mycobacterium avium subspecies paratuberculosis; MAP) in small ruminants has proven challenging for small ruminant stakeholders due to infrequent shedding, subtlety of clinical signs, and a lack of prevalence studies conducted in the United States. To understand Johne’s disease diagnostic trends, Washington Animal Disease Diagnostic Laboratory (WADDL) small ruminant submissions from May 2015 to June 2024 were evaluated. During this period, 108,100 samples were submitted for sheep and goat MAP serum ELISA, and 1,090 for sheep and goat fecal PCR. Ten samples were submitted to outside laboratories for AGID or MAP sheep and goat fecal culture. WADDL utilized two commercial MAP ELISA tests: IDEXX (May 2015 to October 2023) and VMRD (October 2023 to June 2024). In goats, ELISA results revealed a sample prevalence of 1.3% (1,454/108,100) and an individual animal prevalence of 1.2% (1,059/88,466). In sheep, ELISA results revealed a sample prevalence of 3.1% (363/11,667) and an individual animal prevalence of 3.2% (351/11,024). In goats, PCR results revealed a sample prevalence of 7.0% (69/984) and an individual prevalence of 7.1% (68/954). In sheep, PCR results revealed a sample prevalence of 1.9% (2/106) and individual animal prevalence of 2.0% (2/103). The proportion of ELISA to PCR tests show that ELISA tests are the overwhelming choice of small ruminant stakeholders when testing for Johne’s Disease. To compare the agreement between VMRD and IDEXX ELISA, a subpopulation of goat samples (n = 270) with unknown MAP infection status was tested with both ELISAs, showing little agreement (𝜅 = 0.15). To fully delineate the characteristics of ELISA tests in a field setting, a prospective study on herds with known MAP infection status is required.
Conclusions: This study offers valuable insights into the prevalence of MAP infection in domestic goats and sheep across the United States, the preferred tests among producers and veterinarians, and variations in ELISA test characteristics. Study limitations included the preponderance of samples sourced from Washington State as compared to other states within the US, the large volume of samples with variable information provided on submission forms (resulting in the loss of detail and demographic information), and inconsistencies in WADDL’s data management software. Future research would benefit from a prospective study with control groups to further evaluate the performance of the ELISA test in a field setting. For future retrospective studies, improved data collection is essential for developing more efficient means of data analysis. A better understanding of test performances, as well as herd and individual prevalences, will be necessary for the management of small ruminant Johne’s disease within the United States.