bluuebunny/crossref_metadata_2025 huggingface dataset:
Milk Yield, Somatic Cell Counts and Risk of Removal from the Herd for Dairy Cows after Covered Teat Canal Injury
Authors: Querengässer K. , Geishauser T. , Nitschke M.
Published: February 2023

The objective of the study reported here was to evaluate milk yield, somatic cell count (SCC), and risk of removal of cows from the herd after covered teat injury. In covered teat injuries the teat skin is relatively undamaged. Eighty-one patients were used for this study. Teat injuries were diagnosed and treated using endoscopy (Medl et al. 1994). After treatment teats were rested for 3 x 3 days (Geishauser et al. 1998). Each patient was matched to three herdmates by breed, age and calving date. Data on milk yield and SCC were available from DHI records.
Evaluation of Bulk-Tank Culture for the Identification of Major Contagious Mastitis Pathogens on Dairy Farms
Authors: Kelton D. , Alves D. , Smart N. , Godkin A. , Darden P.
Published: February 2023

From May 1997 to December 1998, 40 Ontario dairy veterinarians and 60 dairy producers participated in the Sentinel Herd project. Composite milk samples from all lactating cows were collected and cultured every 4 months. Bulk-tank milk samples were collected from each farm on the day of the fourth herd culture. The objective of this analysis was to describe the prevalence of bacterial pathogens in the bulk-tank samples, the variability of culture results among the repeated samples, and the association of the bulk-tank culture results with the results of the corresponding cow-milk cultures.
Effect of Prepartum Crude Protein Level on Performance of Multiparous Holstein Cows
Authors: Santos J. E. P. , Jardon P. W. , DePeters E. J. , Huber J. T.
Published: February 2023

Recent studies have shown that increasing dietary crude protein (CP) prepartum above National Research Council (NRC) (1989) recommendations does not influence multiparous dairy cow performance. To evaluate the effect of prepartum dietary CP level on performance during early lactation, 64 multiparous Holstein cows were utilized in a randomized complete block design
Cow-Side Milktests for Subclinical Ketosis
Authors: Geishauser T. , Leslie K. , Duffield T. , Kelton D.
Published: February 2023

The objective of this article is to report on the evaluation of cow-side ketosis-tests used with milk to detect subclinical ketosis. Our findings indicate that Pink Milk® and Ketolac® BHB are highly sensitive and specific tests for subclinical ketosis when used with milk. Other tests such as Ketocheck™, Utrecht, Bioketone, Ketostix®, Rapignost®, Uriscan™, Ketur®, Medi, and Azetonreagenz were poorly sensitive but highly specific for subclinical ketosis. Hence, Pink Milk® and Ketolac® BHB may be useful to monitor cows for subclinical ketosis on a regular basis.

Cows with subclinical ketosis produced one to four liters milk less daily (Dohoo and Martin 1984, Duffield 1997). The interval from calving to first service was longer, they needed more services to conceive (Wenninger and Distl 1994), and they were at increased risk of developing cystic ovaries (Gustafsson and Emanuelson 1996), clinical ketosis and displaced abomasum (Duffield 1997, Geishauser et al. 1998b). About 90% of the subclinical ketosis cases were diagnosed within the first two months after calving, and the prevalence of ketosis peaked in the second or third week after calving. Between 10% and 30% of fresh cows already had subclinical ketosis in the first week after calving (Dohoo and Martin 1984, Duffield 1997, Francos et al. 1997). However, losses due to subclinical ketosis can be minimized by early detection and treatment of cows affected (Girschewski et al. 1977).
Levels of D- and L-lactate in Rumen Liquid, Blood, and Urine in Calves With and Without Evidence of Ruminal Drinking
Authors: Grude T. , Lorenz I. , Rademacher G. , Gentile A. , Klee W.
Published: February 2023

Objective: To find out whether ruminal drinking is associated with systemic lactic acidosis.
Use of Flunixin Meglumine as Adjunct Therapy for Bovine Respiratory Disease in Stocker Cattle
Authors: Hellwig D. H. , Kegley E. B. , Johnson Z. , Morris J. , Hunsaker B.
Published: February 2023

Ninety-six stocker calves were purchased from several sale barns in central Arkansas and delivered as a group to the University of Arkansas Beef Cattle Research Facility in Savoy. Processing was done within 24 hours and serum was collected for baseline determination of a-glycoprotein and haptoglobin. The calves were blocked by weight and randomly assigned to 1 of 16, 1.1- acre grass lots, with 6 calves per lot.

Calves pulled for bovine respiratory disease (BRD) from group 1 were treated with flunixin meglumine1 at 2.2 mg/kg body weight, IV and tilmicosin4 at 10 mg/kg, SC when first pulled. Calves from group 2 were treated with tilmicosin at 10 mg/kg, SC without non-steroidal anti-inflammatory (NSAID) therapy. Blood was collected each time an animal was treated for BRD, as well as 48 hours after treatment. Serum was used to determine aglycoprotein and haptoglobin levels using agar gel immunodiffusion5 (AGID).
Dual Infection of the Bovine Fetus with Bovine Virus Diarrhea Type 1 and Type 2
Authors: Chase C. C. L. , Braun L. J. , Brock K. V.
Published: February 2023

Infection of the fetus between 40-120 days of gestation with bovine virus diarrhea virus (BVDV) results in a persistently infected animal that is a constant source of BVDV to the herd.
Clinical Effect of Local Antibiotic Treatment of Digital Dermatitis Lesions and Detection of Spirochetes by Means of PCR
Authors: Dreher M. , Döpfer D. , Mumba T. , Ames K. , Sears P. , Wadell M. , Zwaagstra C. , Plas M.
Published: February 2023

The etiology of digital dermatitis (DD) remains to be fully understood. The disease has been associated with the presence of anaerobic bacteria, though, which most likely are spirochetes (Walker et al., 1997).

The purpose of the study was to monitor the clinical healing process and the recurrence of lesions after topic antibiotic spray treatment. The presence of spirochetes in superficial wound smears taken during the course of the disease was monitored by polymerase chain reaction (PCR).
Prevalence of Major Mastitis Pathogens on Ontario Sentinel Dairy Farms
Authors: Kelton D. , Godkin A. , Alves D. , Lissemore K. , Leslie K. , Smart N. , Church C. , Meadows P.
Published: February 2023

In May and June 1997, 40 Ontario dairy practitioners and 60 of their dairy-producer clients were recruited to participate in the Sentinel Project. Composite milk samples from all lactating cows in each Sentinel herd were collected and cultured during July and August. A milking and management questionnaire was administered to each participating producer at the time of the initial herd culture. Subsequent herd cultures were carried out every 4 months through December 1998. Composite milk samples from all fresh cows were collected 24 hours after calving. Clinical mastitis cases were recorded and quarter samples were collected and stored. The fresh-cow and clinical-case samples were stored frozen and periodically cultured.
Penicillin Residues in Milk Following Subconjunctival Injection of Procaine Penicillin G
Authors: Liljebjelke K. , Warnick L. D. , Witt M. F.
Published: February 2023

Subconjunctival injection of procaine penicillin G is used to treat infectious bovine keratoconjunctivitis. The purpose of this project was to find out how long pencillin can be detected in milk after a single 1 ml bulbar subconjunctival injection of procaine penicillin G.
Plasma and Urine Biochemical Profiles in Grazing Holstein-Friesian First Calf Heifers
Authors: Medina-Cruz Mario , Bouda Jan , Paasch-Martínez Leopoldo
Published: February 2023

The metabolic changes are characterized initially by biochemical alterations in the body fluids (blood, urine, ruminal fluid) and thereafter by reductions in the quantity and quality of milk production, susceptibility to diseases, infertility and increases in morbidity and mortality in calves. Metabolic profiles can be used as monitoring methods for the diagnosis and prevention of subclinical metabolic diseases, for investigation of herd health problems or suboptimal herd performance and for the diagnosis of nutritional deficiencies.3,5,14

The objectives of this research were to determine the dynamics of biochemical parameters in plasma and urine in Holstein-Friesian first-calf heifers.
Strategies for Managing Septic Arthritis of the Digit in Cattle
Authors: Guard Charles
Published: February 2023

Conservative therapy of deep sepsis of the digit is generally unrewarding even with prolonged administration of antibiotics. What we consider prolonged antibiotic administration in bovine practice is clearly different from that employed in other species. In nonruminant species including humans, treatment with antibiotics for septic arthritis typically extends for 2 months or 3 weeks after all clinical signs have resolved. This duration of therapy is clearly not practical in cattle and still might not resolve the types of lesions occurring in the digits. The end result following a common 1 to 2-week course of antibiotics for septic digital arthritis is usually euthanasia or culling after appropriate withholding for drug residues. In the author's opinion, less than 5% of cases of deep digital sepsis respond satisfactorily to such conservative treatment. Why? Possibilities include failure to choose an appropriate antibiotic, inability of the antibiotic to penetrate to the site of infection, or drug resistant strains of bacteria. Most digital infections are caused by a mixed population of bacteria including at least Arcanobacterium pyogenes and Fusobacterium necrophorum; there may also be various Streptococci, Staph. aureus, and other anaerobes involved.8
Liver Abscesses in Beef Cattle
Authors: Nagaraja T. G.
Published: February 2023

The prevalence and economic impact of liver abscesses in feedlot cattle are well documented.7 Abscessed livers in slaughtered feedlot cattle generally result from an aggressive feeding program, with incidence averaging from 12% to 32% in most feedlots.3 Because liver abscesses are secondary to ruminal acidosis and rumenitis, such feeding practices as rapid increase in energy intake and poor or inconsistent bunk management - characterized by irregular feeding (both amounts and intervals) - promote a higher incidence of liver abscesses.4 While abscesses are the leading cause ofliver condemnation, the greatest economic impact of liver abscesses is from reduced animal performance and carcass yield. Reported effects of abscesses on animal performance have ranged from no effect to a depression in daily gain as great as 11% and a decrease in feed efficiency as much as 9.7%.3 Cattle with multiple and/or large liver abscesses also may require more carcass trimming because of adhesion of abscesses to the diaphragm and surrounding organs. In some instances, condemnation of the entire viscera is necessary, contributing to significant economic loss.
How Much Is That Heifer Worth?
Authors: Hughes Harlan
Published: February 2023

My decade of analyzing Integrated Resource Management (IRM) cooperator beef cow herds suggests that heifer retention and replacement strategies have a large impact on long-run profits. What seems to separate profitable beef cow herds from less profitable herds is what is done with the females in the herd and when it is done. Financial problems are frequently exacerbated when replacement heifers are retained at an improper time during the cattle cycle.

The beef cattle cycle typically leads to cash flow "booms" during high-priced times and cash flow "busts' during low-priced times. The beef cattle cycle, its resulting beef price cycle, and resource costs are the three most important factors affecting the long-run profitability and sustainability of today's beef cow producers. The timing of herd expansion, and the buying and selling of females, seem to be particularly critical to the long-run profitability of a beef cow herd. This paper presents a procedure for determining the economic value of a bred heifer at any point in the cattle cycle.
Management of Pregnant Heifers in the Feedlot
Authors: MacGregor Scott
Published: February 2023

Pregnant heifer management is a challenge to the feeding industry. Pregnant heifers represent a loss to the feedyard in numerous areas. Most packing plants don't mind pregnant heifers because they are buying the cattle on a grade and yield basis, and they get the fetal calf serum, which they sell for $25.00 to $110.00 per liter. Therefore when management strategies are evaluated, all of these areas need to be considered. If the last two decades of experience have taught us anything, pregnancy testing on arrival and the judicious use of abortifacients will generate the most cost-effective program.
Surgical and Anesthetic Procedures Performed in Bovine Practice and Proficiency Expected of New Veterinary Graduates
Authors: Morin Dawn E. , Constable Peter D. , Johnson Ann L.
Published: February 2023

Bovine practice is perceived to be changing, with the emphasis shifting from diagnosis and treatment of disease in individual animals toward enhanced production and disease prevention in herds. Therefore, faculty members at veterinary colleges must periodically ascertain the most relevant procedures and skills for veterinarians entering bovine practice, and adjust curricula accordingly. Of particular concern is ensuring that new graduates are proficient in surgical and anesthetic procedures deemed most important by practitioners, given declining case loads at most teaching hospitals and attempts to find alternatives to live animal surgical laboratories. To assist with curriculum adjustment at the University of Illinois, a mail survey was conducted to determine procedures performed most frequently in bovine practice, and skills expected of new veterinary graduates.
Use of Eosin Methylene Blue Agar to Differentiate Escherichia coli from other Gram-negative Mastitis Pathogens
Authors: Leininger Dagny J. , Roberson Jerry R. , Elvinger François
Published: February 2023

Mastitis is a continuous concern for dairy producers in the US because of its economic consequences. Coliform mastitis accounts for 20% to 80% of acute clinical mastitis cases and includes gram-negative pathogens Escherichia coli, Klebsiella and Enterobacter species. Rapid identification of the causative organism is essential to implement a prudent treatment plan. Escherichia coli can be rapidly identified with eosin methylene blue (EMB) agar based on the occurrence of a green-metallic sheen that appears on the surface of the bacterial colonies. The primary goal of this study was to evaluate EMB agar for differentiation of E. coli from other gram-negative mastitis pathogens. The secondary goal was to determine the time to first visible sheen.
Accurate Diagnosis of the Mycobacterium paratuberculosis Status of Cattle Herds
Authors: Smith David R.
Published: February 2023

Programs to classify cattle herds by M. paratuberculosis infection status must satisfy buyer's concerns that cattle from tested herds are unlikely to be infected (high negative predictive value), and seller's concerns that their herds will not be erroneously, classified as infected (high positive predictive value). Veterinarians recommending these programs need confidence that a high percentage of herds will be classified correctly. Probablistic models were used to evaluate 3 diagnostic strategies that use tests of individuals to classify cattle herds by M. paratuberculosis infection status: 1) enzyme-linked immunosorbent assay (ELISA) serology; 2) culture of feces; 3) ELISA serology in series with confirmatory culture of feces.
Diagnosis of A Novel Variant of Bovine Viral Diarrhea Virus Infection in a Bull
Authors: Gnad D. , Debey B. , Kapil S. , Wilkerson M.
Published: February 2023

Bovine viral diarrhea virus BVDV is economically devastating to the beef and dairy industries in most parts of the world, and diagnosing variant strains of BVDV can challenge the practitioner. Being aware of available diagnostic tests and their limitations will aid in making an accurate diagnosis.
Increased Risk of Non-pregnancy Associated with Neospora caninum Infection in Western Canadian Beef Herds
Authors: Waldner C. L. , Cunningham G. L. , Janzen E. D. , Campbell J. R. , Henderson J.
Published: February 2023

The first study examined long-term impact of a N. caninum-associated abortion outbreak in a large northern Alberta cow-calf herd.

Blood samples were collected three times from all bred females and from heifer calves born the spring before the outbreak (average age 7-9 months). These blood samples were collected (1) at the time of the outbreak, (2) the following spring, and (3) again the subsequent fall.
Descriptive Epidemiology of Chronic Disease of Calves in a Western Canadian Feedlot
Authors: Pollock C. M. , Campbell J. R. , Janzen E. D. , West K.
Published: February 2023

A pattern of chronic disease has been recognized in fall-placed, weaned beef calves in western Canadian feedlots. Affected calves become "non-responders" to antibiotic therapy, with weight loss, chronic pyrexia and/or lameness. These calves are moved to a chronic pen for a period of convalescence. This study is describes this pattern of chronic disease in terms of morbidity, days on feed, weight change, and mortality. Its second objective is to determine the association between bovine virus diarrhea virus (BVDV) and Mycoplasma bovis infection and chronic pneumonia and/or polyarthritis in feedlot calves.
Beef Cow-calf Herd Biosecurity Practices
Authors: Sanderson Michael W. , Dargatz David A. , Garry Franklyn B.
Published: February 2023

The literature contains little information on current biosecurity practices of beef cow-calf producers. The cow-calf industry is experiencing an increasingly global marketplace and increasing pressure to minimize antibiotic use and maximize food safety. In this climate, economical biosecurity programs may be an important component of an integrated production management program. Biosecurity programs may be efficiently integrated with Hazard Analysis Critical Control Point (HACCP)-like programs to control food quality and safety, and minimize antibiotic use. This analysis is based on a recent survey on the management and biosecurity practices of U.S. beef cow-calf producers. This analysis identifies current biosecurity practices of beef cow-calf producers, management adjustments to biosecurity risks, and opportunities for veterinary intervention to decrease herd disease risk and risk of quality and safety defects.
New Mutations in Beef Cattle
Authors: Steffen David , Lapointe Jean-Martin , Lachance S. , Sherman Gary , Godfrey Maurice
Published: February 2023

Mutation rates are estimated in the range of 104-106 per generation. This suggests that mutations recur at regular intervals, and inherited phenotypes are likely to emerge or recur in unique breeding populations. In spite of these probabilities, recurrent mutations are not often documented. Syndactyly is a recent example of two mutations that emerged independently in Holstein and Angus cattle. In syndactyly, cattle are born with fused claws. Crossbreeding trials demonstrated the mutation, to be allelic but the phenotypes are distinct, suggesting unique mutations.
Effect of Respiratory Disease on Weight Gain and Infrared Thermal Profiles in Feeder Cattle
Authors: Spire M. , Drouillard J. , Sargeant J.
Published: February 2023

Respiratory disease is the most costly disease of feeder cattle, and remains a major, ongoing concern for health care providers and feedlot operators. Currently, rectal temperature, feed intake, and visual appraisal are used to assess an animal's clinical condition and response to treatment. Marked physiological events associated with disease, adaptation to rations, and acute and chronic stress can modify heat loss or alter blood flow to the body surface and change metabolism in underlying muscle tissues. These changes can lead to alterations in the amount of radiant energy lost to the environment. Thermal imaging measures the amount of infrared radiation on the surface of an animal. Scanning animals with an infrared camera could detect changes in radiant energy loss associated with physiological and pathological events resulting from respiratory disease. This study evaluated the effect on performance and radiant energy loss wrought by clinical illness in feeder cattle with acute respiratory disease.
Epidemiology of Salmonella Fecal Shedding in Naturally Infected Ohio Dairy Herds
Authors: Taylor Carla L. , Wittum Thomas E.
Published: February 2023

Salmonella is a common bovine pathogen that is known to cause severe enteritis and septicemia in cattle of all ages, often resulting in serious economic losses through increased disease or reduced production. The gastrointestinal tract of food animals is also considered to be a major source of food-borne Salmonella infections in humans. However, little is known about the transmission patterns and cycles of infection that allow this bacteria to persist in populations of dairy cattle. The goal of this project was to characterize the population dynamics of Salmonella infection and fecal shedding in naturally infected dairy herds.
Incidence and Impact of Clinical Endometritis in Dairy Cows
Authors: LeBlanc Stephen , Leslie Ken , Duffield Todd , Bateman Ken , Keefe Greg
Published: February 2023

Endometritis is a localized inflammation and/or infection of the uterus, characterized by subinvolution, and associated with chronic bacterial uterine infection and purulent discharge. Diagnosis and treatment of endometritis is a source of controversy among practitioners fueled by lack of large-scale clinical trials with objective case definitions and economically meaningful outcomes. Objectives of this study were to assess diagnostic criteria for endometritis and quantify its impact on reproductive performance.
Effect of Lesion Stage on the Treatment of Digital Dermatitis
Authors: Hemling Thomas , Bathina Harinath , Lising Joy , Siciliano-Jones Joanne , Calaman Jordanna
Published: February 2023

Hairy heel warts disease (digital dermatitis, papillomatous digital dermatitis or PDD) continues to plague the nation's dairies with corresponding profit loss.2 While extensive studies have been conducted on specific treatment compounds and their effects, there has been minimal investigation into the various stages of the disease and their susceptibility and/or resistance to treatment. In this study, correlation between the stage of the disease at which treatment is initiated, and effectiveness of the treatment, is investigated.
Effect of Forage and TMR Particle Size on Cow Health and Milk Components
Authors: Cramer G. , Duffield T. , Kelton D.
Published: February 2023

Particle size of forages and total mixed rations plays an important role in the health and performance of dairy cattle. Objective of this study was to determine the effect of forage and total mixed ration (TMR) particle size on various health and production parameters in Ontario dairy herds.
Characterization of Specific Immune Cell Parameters in Calves Produced by IVF, Microinjection of DNA, and Delivered by Elective Cesearean Section
Authors: Caudell D. , Saker K. , Kalnitsky J. , Bailey T. , Whittier W. D.
Published: February 2023

In vitro fertilization (IVF) and micro-injection of DNA are reproductive technologies available to enhance the genome of production animals. Immune cell function is poorly understood in calves produced by these reproductive methods. Based on economic value and potential use, characterizing immune cell function would aid in better understanding of both management and medicine of calves produced by enhanced reproductive technologies. The objective of this study was to evaluate specific immune cell parameters in these calves.
Comparison of Two Assay Techniques to Study In Vitro Phagocytosis of Bovine Granulocytes Using Flow Cytometry
Authors: Caudell D. , McCourt S. , Kalnitsky J. , Ward D. , Sriranganathan N. , Saker K. E.
Published: February 2023

The response of phagocytic cells to Pasteurella haemolytica is difficult to study in situ. Available assays to study the function of these cell types often do not accurately reflect the physiology of the cell in response to bovine pasteurellosis. This study compared granulocyte phagocytosis of fluorescent beads and fluorescent bacteria using flow cytometry. Development of an in vitro assay would provide a model to study nutrient and pharmaceutical effects on the immune response to Pasteurella infections. It would also allow for future studies of the pathogenesis of not only bovine pasteurellosis but other diseases.
Association Between Ration Protein and Economic Efficiency of Milk Production on Ontario Dairy Farms
Authors: Lissemore K. , Kelton D. , Martin S. W. , Godden S. , Vonk Noordegraaf A. , Edge V. L.
Published: February 2023

An investigation of the association between the protein content of the ration and the economic efficiency of milk production indicates that increasing forage protein on Ontario dairy farms increases the daily milk income minus feed costs (IMFC).
Effects of Prophylactic Administration of a Nonspecific Immune Stimulant on the Performance of Hutch-Reared Calves
Authors: Nosky Bruce J. , Worthington Thomas J.
Published: February 2023

A 75-day study was conducted in 400 beef-production, Holstein-cross calves to determine the effects of administering a single dose of a nonspecific, mycobacterial cell wall fraction immunotherapeutic (Immunoboost®, Vetrepharm, Georgia, U.S.A.) via various routes within the first 24 hours of life.
Evaluation of Lameness in Michigan Dairy Herds
Authors: Kopcha M. , Fowler L. , Bartlett P. , Coe P. , Ames N. K. , Beede D. , Sears P.
Published: February 2023

Lameness in dairy cattle is a well-recognized health concern and is associated with significant economic loss. Numerous studies have investigated lameness with a focus on lesions found in lame cows, rather than a comparison of lesions found in lame and non-lame cows. Moreover, lameness scoring has had but a minor role in lameness research. Objectives of this study were to categorize lesions in lame and non-lame cattle, and correlate them with lameness scores (LS), body condition scores (BCS) and milk production in select dairy cows in Michigan.
Developing Responsible Use of Antibiotics Protocols
Authors: Lawrence Keith
Published: February 2023

The emergence of Bovine Spongiform Encephalopathy (BSE) in Europe and its association with a human disease, variant Creutzfeldt-Jakob (vCJD), has had a profound effect on the psyche of consumers, politicians and regulators. This has been reinforced by thestream of food scares from E.coli 0:157 H:7 to quinolone-resistant Salmonella and PCB contamination in Belgian animal feeds. The result has been an intense interest in the food chain, concentrating on food production methods. Everything that has been seen as accepted practice in the past is now open to challenge. Even the professions are having to justify and defend what they are doing.

Clear evidence of this change in approach within the European Union (EU) has been the ban of hormone growth promoters, beta-agonists, bovine somatotrophin (BST), Genetically Modified Organisms (GMOs) and more recently a group of antibiotic growth promoters that were related to human medicines. There has also been an increasing emphasis on seeking to attach blame for antibiotic resistance in hospitals and the community on the veterinary and zootechnical usage of antibiotics. This has triggered an increasing interest in how antibiotics are used on farms and attempts to measure the quantities used in agriculture. Out of this has arisen a move to promote the 'responsible' use of medicines, which is evident in either the development offormularies or responsible use guidelines.
Implementing Expanded Services or Working Outside the Box
Authors: Day John D.
Published: February 2023

Practitioners are faced with several dilemmas when trying to expand their services. The first is making the decision to add to the current services offered, the second is making time to actually perform those services, and the third is getting compensated for the new services.
What I've Learned about Veterinary Medicine Since Becoming a Dairyman
Authors: Guterbock Walter M.
Published: February 2023

About 20 years after graduating from veterinary school, and after a career in clinical practice, teaching, dairy management, and consulting work, I became managing partner of a dairy farm in Michigan in December 1998. There have been many challenges, but it has on the whole been an interesting and rewarding experience. The experience has intensified some insights into the role of veterinarians on large dairy farms that had slowly been emerging from my previous work as a consultant and dairy manager for the family enterprises of my partners.

The dairy industry is consolidating. Co-ops and processors continue to merge and get bigger. Traditional farms, where family members provided most of the labor, are going out of business as larger producers continue to expand. While the traditional smaller dairy farms will be with us for many years to come, more and more of the nation's milk will be provided by large producers who must use hired labor.
Bovine Mycoplasmosis
Authors: Rosenbusch Ricardo F.
Published: February 2023

Mycoplasmal diseases remain among the most intractable infectious diseases of cattle. Difficulties in diagnosis, poor response to treatment, few preventive measures and increased incidence have converted these diseases into a new frontier for the bovine practitioner. On this frontier, unknown factors and scarce resources create conditions of great danger, and perhaps also opportunity. A regional context is in order. In Asia, Africa, the Middle East, and parts of southwestern Europe contagious bovine pleuropneumonia, caused by Mycoplasma mycoides subsp. mycoides continues to be a problem. Rapidly spreading into new regions, or to regions previously cleared of this disease, the disease represents a continuing world-wide threat.8 Introductions of this endemic disease into North America via infected bovidae have been prevented by prolonged quarantine observations.

In the United States several diseases of bovines that are caused by mycoplasmas can be recognized. Feedlot pneumonia, arthritis, and mycoplasmal mastitis are diseases that can cause severe losses at this time. Pneumonia, arthritis and otitis of young diary calves can also be significant. Some mycoplasmas can play a significant role in enzootic pneumonia of dairy or beef calves. Finally, some diseases of minor importance have been recognized, such as ulcerative vulvovaginitis, ureaplasmal infertility and bovine mycoplasmal conjunctivitis. This paper will only provide an overview of the major bovine mycoplasmal diseases of North America.
Marketing Veterinary Services to Small Beef Producers
Authors: Hilton W. Mark
Published: February 2023

I was in a three person mixed practice in DeWitt, Iowa for fifteen years and we were able to increase our revenue by 90% in the beef cow-calf portion of our practice from 1988 (start of Total Beef Herd Health Program) to 1997. I am quite certain that you can also increase your revenue by initiating some new cow-calf beef programs in your practice.

The beef cow-calf enterprise has critical success factors, and you need to be involved in enhancing the probability of success in these critical success factors.

Various studies show that the critical success factors include:6,71. Knowing your cost to produce 100 lb of beef.

2. Becoming a low-cost, high-profit producer.

3. Reducing feed cost for the cow herd.

4. Learning to optimize vs. maximize. Adding an extra pound of weaning weight is not always cost-effective.

5. Learning that herd improvement does not come from doing one thing 100% better, but from doing 100 things 1% better.

As we look at the entire beef cow-calf enterprise, we can divide it into the following segments:• Herd Health• Fertility• Nutrition• Genetics• Environment• Records• MarketingWhile you as a practitioner surely don't need to be an authority in all these areas, if you want to enhance your business, you should find your areas of expertise and work in these areas.5
Study of the Prevalence of Hemophilus somnus, Mycoplasma bovis and Bovine Virus Diarrhea Virus in Western Canadian Feedlot Cattle Dying with Heart Lesions
Authors: Haines Deborah , Myers Doug
Published: February 2023

Myocarditis has become an increasingly diagnosed cause of death in fall-placed feedlot calves in western Canada. There are few published studies investigating the pathogens involved in this syndrome. The objective of this case control study is to determine the incidence of three proposed agents that are recognized as causes of infection in feedlot calves.
Effect of Estradiol Cypionate in Postparturient Dairy Cattle at Increased Risk for Metritis
Authors: Overton Michael W. , Sischo William M. , Reynolds James P.
Published: February 2023

Metritis is a postparturient uterine disease that adversely affects fertility, milk production, and health of dairy cattle. Although few cows in most herds develop life-threatening septic metritis, many may develop anorexia secondary to metritis-related pyrexia. In an attempt to prevent or reduce the effects ofmetritis, many dairymen have adopted some form of a standardized fresh cow program that often includes administration of 4 mg Estradiol Cypionate (ECP) to postparturient cows with retained fetal membranes. Estradiol has been shown to stimulate uterine contractions, increase phagocytosis of bacteria, increase uterine blood flow, and enhance uterine immune function. However, data is not available to support the use of ECP for prevention of metritis. Recent work by Wagner, et al showed no benefit to the routine use of ECP in randomly assigned postparturient dairy cattle. However, this study contained relatively few cows with known risk factors for metritis. A study was conducted to determine whether the administration of 4 mg of ECP to cows at higher risk for metritis is efficacious in preventing or decreasing severity of metritis in the first 10 days postpartum.
Persistent Infection and Sub-Clinical Bovine Viral Diarrhea Virus Transmission in Dairy Calves
Authors: Hietala Sharon K. , Thurmond Mark C. , Rush Donald M. , Munoz-Zanzi Claudia
Published: February 2023

Clinical disease associated with Bovine Viral Diarrhea Virus (BVDV) has been well documented in the literature and includes respiratory, enteric, hemorrhagic, and reproductive problems. While sub-clinical presence of BVDV in herds is also acknowledged, its significance and impact on animal health and herd economics are not well understood. The objective of our ongoing study is to understand BVDV transmission and how the virus becomes established at a sub-clinical level in typically managed herds. In the first phase of the project, reported here, we focused on identifying sources and extent of BVDV transmission in dairy herds.
Jejunal Hemorrhage Syndrome of Dairy Cattle
Authors: Kirkpatrick M. A. , Timms L. , Kersting K. W. , Kinyon J.
Published: February 2023

Recommendations for investigation of a problem herd are discussed. Our findings suggest that the historical increases in milk production associated with the dairy industry's increases in ration density, as well as overt contamination of haylage, may be creating a new "niche" opportunity for an organism previously considered non-pathogenic.
Field Trial of Intrauterine Antibiotic or Prostaglandin for Treatment of Clinical Endometritis in Dairy Cows
Authors: LeBlanc Stephen , Leslie Ken , Duffield Todd , Bateman Ken , Keefe Greg
Published: February 2023

Endometritis is a localized inflammation and/or infection of the uterus characterized by sub-involution of the uterus, and associated with chronic bacterial uterine infection and purulent uterine discharge. Diagnosis and treatment of endometritis are a source of controversy, fueled by a lack of large-scale clinical trials with an objective case definition and economically meaningful outcomes. The objective of this study was to compare the effect on reproductive performance of two common approaches to the treatment of endometritis.
Homoeopathic Remedies in the Treatment of Mastitis
Authors: Mueller K.
Published: February 2023

There is an increasing demand for organic produce worldwide. In the United Kingdom, the organic food sector shows a growth in retail sale values of approximately 40% per year. Currently, there are about 150 organic dairy farms, with organic milk production predicted to reach 150 million litres in 2003.2 Mastitis affects organically managed cattle to the same degree as conventionally farmed cows, and has been identified as a major concern in organic dairy herds.1 Use of antibiotics for the treatment of sick animals is allowed under organic regulations, but milk and meat withholding periods are extended. In addition, the routine or continued use of antibiotics is prohibited.

Homoeopathy was found to be the main alternative to antibiotics for mastitis treatment in the Hovi and Roderick1 study. However, existing data on the efficacy of alternative therapies is deficient. The current study at Cambridge University aims to establish the efficacy of a commonly used homoeopathic remedy for the treatment of clinical mastitis by comparing it with intramammary antibiotic therapy.
Results of a Seven-Year Surveillance of Milk Safety Related to Use of Ceftiofur Sodium and Ceftiofur Hydrochloride
Authors: Gillette Gary L.
Published: February 2023

In 1991 and 1998, respectively, PharmaciaAnimal Health (PAH) received FDA approval to use Naxcel® Sterile Powder (ceftiofur sodium) and Excenel® Sterile Suspension (ceftiofur hydrochloride) in lactating dairy cattle. Currently, these cephalosporin (penicillin-family) products are the only two that can be used with no milk-discard period. Since 1991, PAH has received about 50 complaints each year where milk adulteration incidents allegedly resulted following proper (labeled) use of these products. To resolve these complaints, we developed a system to determine what actually caused these adulterations.
Evaluation of the ImmunoCardSTAT Rotavirus Assay For On-site Detection of Bovine Rotavirus
Authors: Maes Roger , Grooms Dan , Ciesicki Valerie , Han Cunqin , Wise Annabel
Published: February 2023

Diarrhea is the most important disease in neonatal dairy and beef calves. Significant economic loss occurs due to increased morbidity and mortality, treatment costs and reduced growth rates. Rotaviruses usually cause diarrhea during the first three weeks of life. Clinical signs can be quite variable and are similar to those caused by other neonatal bovine enteropathogens such as corona virus and Eschericia coli.

Diagnosis of rotavirus in calves is based on the identification of viral particles, antigens or nucleic acids in feces. Tests include direct or immune electron microscopy, immunofluorescence, antigen capture enzyme- linked immunosorbant assay (ELISA), latex agglutination and polymerase chain reaction (RT-PCR). All of these tests are useful for diagnosing rotavirus infections, but in general are relegated to use by diagnostic laboratories. Development of an on-site diagnostic assay for bovine rota virus would be a useful tool for veterinarians and cattle producers in making management decisions regarding neonatal bovine diarrhea.

The ImmunoCardSTAT Rotavirus (ICS-RV) Assay (Meridian Diagnostics, Cincinnati, OH) is a patient-side assay designed to detect group A rotavirus in humans. This assay is based upon rapid immunomigration (RIM) technology. This technology allows for packaging of all reagents into a single-step assay that can then be used patient-side (similar to a "home pregnancy test"). The objective of this study was to evaluate the ICS-RV assay's usefulness as an on-site diagnostic test for bovine rotavirus.
Evaluation of Milk Urea Nitrogen Levels on Bulk Tank Milk and Individual Cow Milk
Authors: Arunvipas P. , VanLeeuwen J. , Dohoo I. , Leger E. , Keefe G.
Published: February 2023

There are two purposes of this research: 1) to evaluate the repeatability, precision and accuracy of milk urea nitrogen levels (MUN) using an infrared test, the Fossomatic 4000 MilkoScan analyzer (Foss 4000) at the Prince Edward Island Milk Quality Laboratory (PEIMQL), compared with an enzymatic reference method conducted at the laboratory of the Ontario Dairy Herd Improvement Corporation (ODHIC); and 2) to determine the representativeness of bulk-tank MUN (BTMUN) as a herd representation of the MUN levels.
Evaluation of Two Treatment Protocols against Staphylococcus aureus at Drying-off
Authors: Castillo Jorge , Bouchard Émile , DesCôteaux Luc , Dutil Lucie
Published: February 2023

A lot is known about control strategies to treat and prevent Staphylococcus aureus mastitis in dairy cattle. However, S. aureus continues to be one of the major causes of mastitis in dairy herds worldwide. The efficacy of current lactating cow antimicrobial therapy is clearly limited. Although intra-mammary dry cow therapy improves cure rate, the high proportion of treatment failures prevents this procedure from forming the basis for an effective control program. It has been suggested that extended lactational therapy prior to drying-off might improve cure rate. The goal of this study is to compare the efficacy of two treatment protocols, using either the combination of novobiocin and penicillin as a dry cow therapy (Novodry plus®), or the same treatment preceded by 3 complete treatments with Pirlimycin (Pirsue®), on bacteriological cure and reduction of somatic cell count (SCC) in cows infected with S. aureus.
Impact of Treatment with Monensin Controlled-release Capsule on Blood Biochemical Constituents
Authors: Cécyre Dominique , DesCôteaux Luc , Brodeur Marcel , Tremblay Armand V.
Published: February 2023

In the context of a large, post-approval randomized clinical trial on Rumensin CRC®, blood samples were collected to determine the impact of treatment on different blood constituents of lactating dairy cows. This study was performed on 730 cows from 38 Quebec herds. Cows were randomly assigned to receive a Rumensin CRC capsule (n=354) or a placebo capsule (n=376) between two and four weeks before the expected calving date. Two blood samples were taken for each cow: once between two and four weeks postpartum and again between six and eight weeks postpartum. Blood analyses were performed on serum for the following biochemical constituents: glucose, urea, total protein, albumin, GGT, AST, potassium, inorganic phosphorus, calcium, Na, Cl, total CO2, Mg, cholesterol and B-hydroxybutyrate (BHB).

Herd means for serum BHB were calculated from the first blood samples taken from the placebo cows. Those means were ranked, and three groups of risk for ketosis were created based on quartiles. For the low-risk-for-ketosis (LRK) herds, herd BHB mean was in the first quartile; for the medium-risk-for-ketosis (MRK) herds, between the first and third quartile; and for the high-risk-for-ketosis (HRK) herds, in the fourth quartile. A linear mixed-effect model (proc mixed in SAS) was applied to assess the effect of treatment on each biochemical constituent. Herd was entered in all models as a random variable and the following variables were included in the models to control for their fixed effects: treatment, biochemistry number, herd risk for ketosis, cow's level of production, herd's level of production, type of feeding, group of lactation and body condition. Interactions of each fixed variable with treatment were also verified. Tests for BHB were performed on log transformation.
New Diagnostic Test for the Detection of Bovine Leukemia Virus (BLV) Infection in Cattle
Authors: Connelly Holly , Kelsey David , Reeve Elizabeth , Luck Michael , Crabb Joseph
Published: February 2023

Bovine leukemia virus (BLV) is a retrovirus infection of both dairy and beef cattle known to cause bovine leukosis and malignant lymphoma. Clinical signs of the disease, such as weight loss and decreased milk production, yield economic losses. Moreover, trade restrictions are placed on positive animals. Since there is no vaccine or treatment, biosecurity measures can help control the spread of the disease. Current testing methods, although highly sensitive and specific, require the practitioner to send in samples to a specialized laboratory. The turnaround time for results can be on the order of a few days to a few weeks. Tip-Test™: BLV (ImmuCell Corporation, Portland, Maine) has developed an on-site, rapid serological test for the presence of anti-BLV antibodies. The test is based on the enzyme-linked immunosorbent assay (ELISA) principle, yet provides results in 25 minutes and can be used with whole blood, serum or plasma. This self-contained kit requires no specialized equipment or laboratory and can be used by practitioners in the clinic or on-site.
Effect if an Orally Administered Antacid Agent Containing Mg(OH)₂ and Al(OH)₃ on Abomasal pH in Milk-fed Calves
Authors: Ahmed A. F. , Constable P. D. , Misk N. A.
Published: February 2023

Abomasal ulceration occurs commonly in milk-fed calves and adult cattle, and severe ulceration can result in abomasal perforation, peritonitis and death. An important therapeutic goal in treating gastric ulceration in monogastric animals is maintaining gastric pH >3.5 by administering oral antacid agents, proton pump inhibitors, or histamine H2-receptor antagonists. Because the efficacy of oral antacid agents in increasing abomasal pH is unknown in cattle, the purpose of this study was to determine the effect of a widely available oral antacid agent (Extra-strength Maalox®) on abomasal pH in calves. This antacid contains 90 mg of Mg(OH)2 and 100 mg of Al(OH)3 per mL, and the antacid increases gastric pH through the following chemical reactions:Mg(OH)2 + 2H+ ⇒ Mg2+ + 2H2OAl(OH)3 + 3H+ ⇒ AI3+ + 3H2O

Purportedly, Mg(OH)2 / Al(OH)3 antacid agents have clinical efficacy in the treatment of abomasal ulceration in adult cattle. There do not appear to be any data available to support or refute such a claim.
Comparison of Three Different Methods of Serological Testing for the Presence of Antibodies to Neospora caninum in Beef Cattle
Authors: Cunningham Gail , Waldner Cheryl , Campbell John , Janzen Eugene , Polley Lydden
Published: February 2023

Several serological tests for the presence of antibodies to Neospora caninum are commercially available. These tests have all been used in current N. caninum research, but limited information is available on the level of agreement between them. This makes it difficult, to compare serological results from research projects that use different testing methods. The objective of this study was to test the level of agreement between three different commercially available serological tests for antibodies to Neospora caninum.
Evaluation of Vaccinations of Calves and their Impact on Feedlot Performance
Authors: Fulton R. W. , Cook B. J. , Step D. L. , Confer A. W. , Saliki J. T. , Welsh R. D. , Blood K. Shawn
Published: February 2023

The objective was to assess vaccination programs for calves in a Retained Ownership Program (ROP) and their effect on feedlot performance.
It is Feasible to use Test-day Information (DHI Milk Control Data) for the Estimation of Energy Uptake in Dairy Cows
Authors: Heuer C. , Schukken Y. H. , Van Straalen W. M.
Published: February 2023

Low energy balance increases the incidence of disease and contributes to poor reproductive performance. Monensin (an ionophore) increases energy precursors in the rumen. Monensin-treated cows had higher milk yield and lower serum ketone bodies, and thus better energy status, than control cows. This study aimed to validate a previously developed model for the prediction of energy balance from test-day information. Predicted energy balance was compared for cows with or without monensin supplementation.
Risk Factors for Neospora caninum Infection and Associated Abortion in Ontario Holstein Dairy Herds
Authors: Hobson J. , Duffield T. , Peregrine A. , McEwen B. , Hietala S. , Kelton D. , Lissemore K. , Leslie K. , Cramer G.
Published: February 2023

Neospora caninum has been identified as a major cause of abortion in dairy cattle worldwide. The objective of this component of an epidemiological study investigating N. caninum in Ontario was to identify risk factors for N. caninum serostatus and related abortions in Ontario Holstein dairy herds.