bluuebunny/crossref_metadata_2025 huggingface dataset:
Distribution of Mycobacterium avium paratuberculosis in Minnesota Dairy Farms Using Bacterial Culture of Fecal Pools
Authors: Raizman E. A. , Wells S. J.
Published: February 2023

Paratuberculosis, or Johne's disease, is a chronic and progressive intestinal disease in ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). The usual route of infection is fecal-oral, with young cattle becoming infected by exposure to infected adults or their contaminated environment. The disease becomes manifest in adulthood and results in economic losses due to premature culling, reduced milk production and loss of body weight in cattle sold for slaughter. Johne's disease control programs have been developed in different countries and in several US states, with a goal to test and classify herds of cattle as infected or presumptively non-infected with maximum accuracy and least cost. Generally, these programs utilize recognized laboratory tests such as ELISA or direct microbiological individual fecal culture. However, these tests have several disadvantages, especially when applied in herds with subclinical disease or low prevalence. A pooled fecal culture method, which aggregates several cows' fecal samples to one culture unit, has been recently suggested as a good alternative strategy for lowering the procedure cost for herd screening programs for dairy cattle. The objectives of the current study were to: 1) describe the apparent fecal pool prevalence of MAP in known to be infected and non infected Minnesota dairy herds based on pooled fecal culture, 2) estimate the animal-level prevalence based on fecal pool results, 3) characterize the association between cow age and pool status and shedding level results, and 4) characterize the association between pooled culture results and serum ELISA results at the herd level.
Evaluation of Diagnostic Tests for Johne's Disease Using Detection of Mycobacterium avium Subspecies paratuberculosis in Tissues to Classify Infection Status of Dairy Cows
Authors: Lombard J. E. , Hirst H. L. , Antognoli M. C. , Salman M. D. , Garry F. B.
Published: February 2023

Interpretation of Johne's disease (JD) diagnostic tests is not always clear to determine the infection status of animals. Multiple tests on an individual animal are often not in agreement. The objectives of this study were to determine the association between infection status of individual dairy cows, based on postmortem histopathology and culture of multiple tissues, and the previous results of fecal culture and multiple serum ELISA tests.
Effect of Presence of Claw Lesions in Heifers Prior to First Parturition on Risk of Developing Claw Lesions during Lactation
Authors: Drendel T. R. , Hoffman P. C. , St. Pierre N. , Schugel L. M. , Socha M. T. , Tomlinson D. J. , Larson C. K.
Published: February 2023

According to the 2002 National Animal Health Monitoring Systems (NAHMS) survey, 16% of cattle are culled due to lameness. However, this survey may underestimate this number, as cows culled for low production (19%) or reproductive failure (27%) may actually have been lame. Lameness has been shown to reduce milk production (Guard, 1997; Robinson et al, 2003) and fertility (Sprecher et al, 1997; Hernandez et al, 2000; Melendez et al, 2002). Furthermore, dairy producers tend to underestimate extent and severity of lameness within their herd (Whay et al, 2002). Literature also indicates that previously lame cattle are more prone to future recurrences (Peterse, 1986; Raven, 1989; Enevoldsen et al, 1991). Therefore, preventing animals from becoming lame must be a key management objective. However, there is limited data on incidence and severity of claw lesions in calves and heifers. Data is also limited on the impact of claw lesions during the rearing phase on reoccurrences of claw lesions during lactation. The objective of this study was to determine incidence and severity of claw lesions in heifers from 12 months of age to calving and the impact of claw lesions during the rearing phase on recurrence of claw lesions.
Vaccination Programs for Breeding Heifers using Combinations of Killed and Modified-Live BVDV Vaccines
Authors: Dubovi E. J. , Grohn Y. T. , Nydam D. V.
Published: February 2023

Despite preventing morbidity and mortality in properly immunized cattle, sometimes bovine viral diarrhea virus (BVDV) vaccines have failed to prevent reproductive consequences of BVDV infection, in particular, persistently infected animals.

High (SN) titers may provide fetal protection in at-risk breeding heifers. Our objective was to test different types and sequences of administration of killed and modified-live virus (MLV) vaccines to determine which produced the greatest titer response.
Lameness Treatment Rates in Wisconsin Dairy Herds
Authors: Cook N. B.
Published: February 2023

Few studies have documented lameness treatment rates in North American dairy herds. Case definition, ability to detect lame individuals and frequency of delivery of the hoof trimming program significantly impact the incidence of new and recurrent cases.
Effect of Lameness in Fresh Cows on Milk Production and Somatic Cell Counts on a Large Commercial Dairy
Authors: Stockler R. M. , Neuder L. M. , Sears P. M.
Published: February 2023

Lameness in dairy cattle is a both an economic and welfare issue for most dairies. Lameness is defined as the departure from the normal stance or gait of an animal. This is the result of a structural or functional disorder of one or more limbs. Lameness can affect the cows feed intake, body weight, milk production and place them at a greater risk of culling. This study was designed to follow cows right after calving and evaluate the effect of being lame on early and peak milk production and level of milk somatic cell counts at freshening. The hypothesis proposed is that clinical lameness causes losses in milk production and high somatic cell counts.
Comparison Of Commercial ELISA Tests For Johne's Disease In Beef Cattle Herds
Authors: Heeb Matt , Austerman S. R. , Hall Jason , Evans R.
Published: February 2023

The prevalence of Johne's disease throughout the United States has prompted the development of several USDA approved ELISA kits. These test kits are widely used in diagnostic labs throughout the country. As numbers of beef producers utilizing these ELISA tests to detect Johne's disease increase, it becomes important to critically evaluate the performance of these diagnostic tests specifically in beef cattle.

The aim of this study was to evaluate the specificity and agreement between the three commercially manufactured ELISA tests for Johne's in beef cattle herds. Two-thousand fifty-four sera samples were collected from six beef herds in Iowa, South Dakota and Georgia. The samples were ran according to manufacturer's recommendations. The results were evaluated based upon specificity in negative herds, and kappa statistics were calculated for both positive and negative herds. The specificities ranged between 90.48 and 9.41 %. Agreement between tests ranged from k-0.394-0.061 in negative herds and k-0.503-0.310 in positive herds. These data indicate a significant difference between commercial ELISA tests.
Johne's Disease as a Probable Cause for Higher Culling Rate in Cows with Left Displaced Abomasum and Diarrhea in a Dairy Herd in Iran
Authors: Kasravi R. , Nowrouzian I.
Published: February 2023

According to a few previous reports, cows with left displaced abomasum (LDA) presenting with diarrhea respond less favorably to surgery and appear to be at a greater risk of removal from the herd compared to cows presenting with normal feces. However, there is a paucity of information in the literature about the probable relationship of Johne's disease (JD) to the higher culling rate.
Transmission of Mycoplasma bovis and the Syndromes that Result in Beef and Dairy Cattle
Authors: Rosenbusch Ricardo F.
Published: February 2023

Infections with Mycoplasma bovis can result in several syndromes of importance for dairy and beef cattle of all ages. These diseases continue to require the attention of practitioners due to poor response to treatment and the marginal effectiveness of prophylaxis. We explore here parameters of transmission of the infections, and how practitioners can use this knowledge to develop management strategies. General concepts about transmission of the mycoplasma are followed with specific description of several different mycoplasma mastitis clinical presentations. Issues with transmission and mastitis are outlined. Pneumonia and polyarthritis, and middle ear infections in dairy calves are described next and transmission of infection differences are highlighted. Examples of presentations of pneumonia and polyarthritis in beef calves are presented together with discussion of some of the transmission questions that are commonly raised when considering this disease.
Treatment of Mycoplasma Infections: Susceptibility of Field Isolates and Outcome of Treatment
Authors: Ayling Roger D. , Nicholas Robin A. J.
Published: February 2023

A number of Mycoplasma species cause disease in cattle including Mycoplasma niycoides subspecies mycoides small colony type, the cause of the OIE list A disease, contagious bovine pleuropneumonia in Africa, and Mycoplasma bovis, one of the biggest causes of calf pneumonia world-wide. Symptoms include pneumonia, mastitis and arthritis, all of which adversely affect the economics of farming. Control of M. bovis is difficult because it has systems for evading the immune system and has developed resistance to a number of antimicrobials. While strategies can be deployed on the farm to reduce or possibly eliminate disease caused by M. bovis, these approaches can be time consuming, and costly in terms of drug treatment and testing, with no guarantees of success. Although some vaccine trials have seen an exacerbation of disease, vaccines are being developed, and some are in use in the USA, although data on their efficacy is sparse.
Practitioners Experience with Mycoplasma bovis Outbreaks
Authors: Gawthrop Jan C.
Published: February 2023

Mycoplasma bovis infection in dairy calves is a very common problem that requires all the common principles of good medical management. Reduce exposure, detect early, treat properly, feed and house optimally and vaccinate if necessary. More knowledge on management of this disease is surely needed.
Choosing a New Vaccine
Authors: Tremblay Robert
Published: February 2023

Vaccination is an integral part of disease prevention and control programs in dairy and beef production systems. Despite widespread acceptance of vaccination, many aspects of vaccination are controversial. Veterinarians are often confronted with implementing or changing vaccines and vaccination programs without having access to adequate information. This paper addresses controversial issues related to the implementation of modified-live viral vaccine programs and the selection of BVD and BRSV vaccines.
Histophilus somni
Authors: Clark Ted
Published: February 2023

Haemophilus somnus has recently been renamed Histophilus somni and it has been proposed this name also includes Haemophilus agni and Histophilus ovis. The organism occurs in all management systems of the cattle industry, but the most serious losses occur in beef feedlots where co-mingling of cattle from numerous farms occurs. The disease in feedlots most often manifests as the septicemic form and is known as the Histophilus somni disease complex (HSDC), but pleuritis and bronchopneumonia are two other very common causes of disease or death. Despite effective vaccines and antibiotics,  sudden losses from 30 to 90 days after arrival at feedlots continue to occur in significant numbers, especially in certain geographical areas ofNorth America and Europe. There undoubtedly remains much to be learned about predisposing factors to histophilosis and how this organism avoids natural body defense mechanisms.
Implementing New Procedures on My Own Dairy
Authors: Niles Donald E.
Published: February 2023

In a decade and a half of dairy practice, I had the luxury of remaining outside the actual "black box" of the dairy's inner workings. By this, I mean even when working directly with the herd manager, or even the owner himself, I was able to maintain a polite distance from the actual process of implementing my recommendations. Instead, I would make a management recommendation, often of unparalleled insight and breathtaking intuition, and insert it into the black box. Shortly thereafter, the appropriate management change would occur and be well entrenched by my next visit. Occasionally, if I was very lucky, there would be some holdup or breakdown in the implementation of the new procedure, which would allow me to use some of my best and wittiest consultant lines such as ''Why are only some of your milkers ... ", or, my personal favorite, "I thought we agreed you were going to ... " The pleasure I took from my client's discomfiture was reward enough for all my labors.

Now, however, I live in the black box. As a veterinarian who is both owner and manager of a 1500-cow dairy, it is my job to implement change, monitor results and look for opportunities to keep moving ahead. Now, as my advisors make recommendations, I need to evaluate the value of the recommendations as well as determine whether the dairy has the energy and resources to make the suggested change(s). This talk is intended to address that process.
Managing the Organic Dairy
Authors: Fry Robert C.
Published: February 2023

Management of cows in certified organic dairies requires an understanding of organic protocols and regulations for veterinarians and producers. If a dairyman chooses to manage his or her cows under organic guidelines, specific principles of management that are unique to organic production must be coupled with best-known traditional management practices used in non-organic herds. Management systems and protocols are reviewed for a 600-cow operation in Maryland producing certified organic milk since 1998.
Milking Cows Four and Six Times per Day (4X-6X) and its Impact on Animal Performance
Authors: Dahl Geoffrey E.
Published: February 2023

Increasing the frequency of milk removal increases absolute milk output in cows during an established lactation. Recent studies indicate that high frequency of milking in the first three weeks of lactation can produce lasting increases in persistency after the milking frequency returns to 2 or 3X. This approach reduces the labor requirement of continuous frequent milking. However, a number of management factors need to be considered to effectively implement increased milking frequency. This paper presents evidence of the response, describes collateral effects and discusses possible limitations to implementation.
Applications of Biotechnology in Today's Dairy Industry
Authors: Oliver S. P.
Published: February 2023

Advances in biotechnology and molecular biology in the last decade or so have brought exciting new technologies that can/will be used to solve complex problems confronting animal agriculture. These advances could have a fundamental impact and perhaps revolutionize production agriculture systems as we now know them. For example, improved disease surveillance; enhanced disease resistance; increased animal growth, efficiency and productivity; and manipulation of food quality and quantity are just a few possibilities that could impact the agricultural sector in the not-too-distant future. The purpose of this communication is to describe how biotechnology and molecular biology are used in research on mastitis, food safety and foodborne pathogens, and whenever possible describe how these advances have/will impact food-producing animals with particular emphasis on the dairy industry.
Incorporating Veterinary Care into the Sheep Production Cycle
Authors: Van Metre David C.
Published: February 2023

According to recent national survey data, roughly half of sheep producers in the United States regularly utilize veterinary consultation as a diagnostic service. A large proportion of health problems in conventional flocks is the result of management errors and is potentially preventable. Veterinarians are well positioned to provide consultation services to improve management practices as well as diagnostic services to monitor health and disease in the animals. A logical starting point is the introduction of certain practices that have high potential to provide direct economic benefit to the producer, such as fertility testing of rams. By 0ffering such services at opportune times, veterinarians can efficiently integrate their expertise into the annual flock production cycle.
Herd-based Testing for the Preventive Medicine Practice
Authors: Oetzel Garrett R.
Published: February 2023

Strategies have been developed to diagnose and monitor key metabolic and nutritional diseases in dairy herds. Veterinary technicians can play a key role in gathering and managing the herd-based data needed. Tests that can be used include ruminal pH (for subacute ruminal acidosis), blood β-hydroxybutyrate (for subclinical ketosis), cowside ketone tests (for identifying individual cases of ketosis), blood non-esterified fatty acids (for evaluating energy balance on pre-fresh cows), blood calcium (for parturient hypocalcemia) and urinary pH (for monitoring acidification of pre-fresh cows to prevent hypocalcemia).
Multiattribute Evaluation of Two Simple Tests for the Detection of Cryptosporidium parvum Oocysts in Calf Feces
Authors: Trotz-Williams Lise A. , Martin S. Wayne , Martin Donald , Duffield Todd , Leslie Kenneth E. , Nydam Daryl V. , Sockovie E. , Peregrine Andrew S.
Published: February 2023

Cryptosporidium parvum is increasingly recognized as an important pathogen in neonatal dairy calves. As a result, there is a need for simple, inexpensive and quick methods for the detection of C. parvum infection in calf feces. Most diagnostic and screening methods for this parasite that are currently in common use, such as concentration and staining methods and immunofluorescence (Kvac et al, 2003), are expensive and time-consuming, and as such are unsuitable for the screening of large numbers offecal samples in veterinary practice or research. At the Ontario Veterinary College (OVC), a simple sucrose wet mount method without centrifugation has been in use for some time. However, to the authors' knowledge, there are no published reports that have evaluated the performance and utility of this method when used for the detection of C. parvum oocysts in calf feces. In this study, the OVC sucrose wet mount method and a lateral immunochromatography test for detection of C. parvum antigen in feces (BioX Diagnostics, Jem~lle, Belgium) were evaluated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with gel electrophoresis as a gold standard.
Effect of Feeding Medicated or Non-medicated Milk Replacer on Growth, Morbidity and Mortality of Holstein Heifer Calves
Authors: Averill J. J. , Erskine R. J. , Bartlett P. C.
Published: February 2023

With the emergence of antimicrobial resistance in the medical communities, the agricultural community has been heavily scrutinized on how antimicrobial agents are used. This has led to calling for more prudent use of such drugs in animal agriculture. Given the advances in veterinary preventive medicine, some question the necessity of adding antimicrobial agents to milk replacer for dairy calves. The purpose of this study was to determine the effect of feeding milk replacer with or without antimicrobial agents on growth, morbidity and mortality in dairy heifers.
Fecal Shedding of Mycobacterium avium subsp paratuberculosis in Calves
Authors: Bolton Michael W. , Grooms Daniel L. , Kaneene John B.
Published: February 2023

It is widely accepted that most infections caused by Mycobacterium avium subsp paratuberculosis (MAP) occur in utero or in the neonatal animal. The challenge, however, has been to demonstrate and detect the infection in the young animal, as the onset of clinical signs often takes several years. Earlier detection may allow for more prudent animal management decisions. Two primary objectives of this study are to determine whether fecal shedding of MAP can be detected in naturally infected young animals and if there is a relationship between MAP-shedding cows and fecal shedding in their offspring. This was a longitudinal, prospective study of two years' duration with more than 1,600 samples. It is a cooperative study with MSU, USDA, Michigan Dairy Association, private practitioners and dairy producers.
Clinical and Subclinical Diseases Predisposing to Johne's Disease in Dairy Cattle
Authors: Raizman Eran A. , Wells Scott J. , Godden Sandra M.
Published: February 2023

Paratuberculosis or Johne's disease (JD) is a chronic and progressive intestinal disease in ruminants caused by Mycobacterium avium subsp paratuberculosis (MAP). The usual route of infection is fecal-oral, with young cattle becoming infected by exposure to infected adults or their environment. The factors that trigger MAP fecal shedding or JD clinical disease are not understood and little information is provided about it in the literature; why do some cows that already shed the organism in the feces suddenly break into the clinical phase, whereas other shedding herdmates continue in the subclinical phase? The objectives of this study were to identify associations between clinical or subclinical diseases and risk for subsequent occurrence of clinical Johne's disease (JD) and onset of fecal shedding after 305 days in milk (DIM).
Efficacy of Monensin Sodium for the Reduction of Fecal Shedding of Mycobacterium avium subsp paratuberculosis in Infected Dairy Cattle
Authors: Hendrick S. H. , Kelton D. F. , Leslie K. E. , Lissemore K. D. , Archambault M. , Bagg R. , Dick P. , Duffield T. F.
Published: February 2023

Reducing the quantity of Mycobacterium avium subsp paratuberculosis (MAP) being shed by cows with Johne's disease should decrease the risk of spread of this disease to young stock. Previous work has suggested that monensin sodium decreases the pathologic lesions associated with Johne's disease, but the impact on shedding of viable MAP remains unknown.
Efficacy of Intramammary Pirlimycin as a Pre-calving Antibiotic Treatment for Nulliparous Heifers
Authors: Roy J. -P. , Du Tremblay D. , DesCôteaux L. , Messier S. , Bouchard É.
Published: February 2023

Recently, more and more studies indicate that intramammary infection (IMI) in peripartum heifers are frequent and associated with financial losses. The objective of this study was to evaluate the effectiveness of an intramammary antibiotic treatment (pirlimycin) during the pre-calving period on the proportion of intramammary infection (IMI) in heifers at the onset of lactation as well as on milk production and somatic cell count (SCC) during their first lactation.
Effect of Prepartum Intramammary Treatment of Heifers on Somatic Cell Count, Milk Production and Mastitis Postpartum
Authors: McCarthy K. K. , Kreft R. A. , Sears P. M.
Published: February 2023

Mastitis in heifers has been the topic of numerous studies in the past few decades. Many studies have concluded that a large percentage of heifers began their first lactation with intramammary infections (IMI), usually with coagulase-negative Staphylococcus (CNS) species. These bacteria are ubiquitous on skin and hair of heifers, and then colonize the teat canal and gland. Several studies have examined the outcome of prepartum intramammary antibiotic therapy in heifers and have shown antibiotics are successful at reducing infections.1,2 However, results have varied on the benefit of reducing these infections. Oliver et al2 found prepartum intramammary antibiotic therapy in heifers increased milk production ( + 1000 lb; 454.5 kg) and decreased somatic cell count (SCC) linear score (-0.6) significantly over untreated animals. Treatment was demonstrated to be profitable, as long as the increase in milk production is greater than 84 lb (38.1 kg).4 In the seven-state study,1 prepartum antibiotics were effective in curing IMI in heifers, but the differences in SCC and milk production between treatment and control groups were small. The goal of this study was to treat prepartum heifers with intramammary antibiotics and monitor SCC, cultures and milk production during the first part of their lactation to determine the efficacy and value of therapy.
Relationship between Locomotion Scores and Lameness Lesions in Dairy Cattle
Authors: Cramer Gerard , Lissemore Kerry , Kelton Dave , Guard Chuck , Leslie Ken , Laferriere Janyk
Published: February 2023

To preserve and improve the perception that the dairy industry has among consumers, there is a need to be able to identify and act upon animal welfare concerns. Lameness is the dairy industry's most visible animal welfare concern. Unfortunately, dairy producers often underestimate the level of lameness on their farm. Bovine practitioners need to take a leadership role in assisting the dairy industry in monitoring and reducing lameness. To meet this challenge, accurate methods to diagnose lameness early is needed. A variety of locomotion scoring systems are used to assess lameness. However, few of these systems have correlated the score assigned to a cow with the lesion present in the claw. The objective of this project was to evaluate the association between locomotion scoring and lesions found at the time of foot trimming.
Johne's Disease
Authors: Whitlock R. H. , Sweeney R. W. , Fyock T. , McAdams S. , Gardner I. A. , McClary D. G.
Published: February 2023

Johne's disease (paratuberculosis) is a chronic, granulomatous infection of the intestinal tract of ruminants caused by Mycobacterium avium subspecies paratuberculosis (MAP). There is no approved treatment, no known way to eliminate the infection once established, nor is there an effective vaccine for the disease. Johne's disease (JD) has emerged as an important disease of cattle due to the economic impact and the potential link to human Crohn's disease. The recently introduced herd Risk Assessment (RA) and Herd Management Plan (HMP) developed by the National Johne's Working Group (NJWG) have been incorporated into the national program standards by USDA, APHIS. Increased state and federal funding for Johne's disease has increased the focus on ways to control the condition. Methods to control the spread and to reduce within herd transmission of Johne's disease (JD) are being adopted by both dairy and beef herds in many states through implementation of the national Johne's disease program. Implementation of best management practices (BMP) following a herd risk assessment (RA) designed to reduce the risk of transmission of JD remains the focal point of the national effort to reduce the prevalence of JD in cattle herds today. Although a vaccine for JD is available in many states, its use is closely regulated by individual state veterinarians and usage by the profession remains less than 2,000 herds nationally. Test and culling of culture-positive cattle seems a low priority if the infected animals are profitable. Reduction of the herd bioburden of MAP seems a lower priority for many producers. Brumbaugh et al1 demonstrated a reduction in the number of colony forming units (cfu) of MAP from the livers of experimentally MAP-infected mice treated with monensin compared to non-treated controls. More recently he showed monensin reduced the severity of histological lesions in cattle with clinical signs of Johne's disease, including weight loss and diarrhea.2 Initial infection with MAP is generally considered to occur in the neonatal calves. Our laboratory at the University of Pennsylvania, New Bolton Center has successfully induced experimental MAP infection in neonatal calves via oral gavage of MAP on two consecutive days.4 The current experiment was designed to assess the efficacy of monensina to reduce pass-through fecal shedding and to reduce tissue bacterial load (bioburden) of MAP in calves.
Prevalence, Risk Factors and Treatment of Postpartum Anestrus in Dairy Cattle
Authors: Walsh R. B. , Walton J. S. , Leslie K. E. , LeBlanc S. J.
Published: February 2023

Reproduction remains a significant limiting factor to the achievement of economic goals on dairy farms. Dairy producers are making increasing use of management aids, such as estrus detection devices and estrus or ovulation control programs, to mitigate the impact of poor heat detection. While such management aids are useful, their success is dependent on the rate that animals return to a predictable estrus cycle. The objectives were: 1) to determine the prevalence of anestrus in Ontario dairy herds, 2) to evaluate herd and cow level risk factors for anestrus and 3) to investigate the impact of a progesterone releasing intravaginal device (PRID) on days to first service, first service conception risk and days from calving to conception in animals at risk of anestrus.
Risk Analysis for Beef Cow-Calf Retained Ownership Decision Making
Authors: White B. J. , Anderson J. D.
Published: February 2023

Cow-calf producers recognize the value of postweaning performance information and have collected a large volume of data through alliances and university feed-out programs. These statistics are largely used to address and guide production decisions including genetic, health and management issues. Value Based Marketing (VBM) of fed cattle is increasingly popular, and individual animal value is determined based on specific carcass merits. This system of marketing increases income variability compared to traditional liveweight marketing of fed cattle. This research is designed to illustrate how feedlot and carcass performance information can be incorporated into the cow-calf producer's risk analysis decisions regarding retained ownership from weaning to harvest. Economic risk of retaining ownership is based on uncertainty of market conditions, cattle performance and expected income based on carcass merits. This study addresses utilization of historical performance data to compare the market value of feeder cattle with their expected value as finished cattle in a VBM system. From a feeder cattle producer's perspective, this is a very important issue. If, from past experience with the same or similar genetics and management, a producer knows with some degree of certainty that his cattle will perform well in the feedlot and/or in terms of carcass merits, then the market price may significantly undervalue those cattle. The producer would be better off to retain ownership of the calves or to market feeder cattle through some alternative means (e.g., direct sales to a cattle feeder with knowledge the cattle's performance potential) in order to receive a price that more accurately reflects their true value.
Fetal Protection Against a Type 2 Bovine Viral Diarrhea Virus (BVDV) Challenge in Cattle Vaccinated with a Type I Modified Live BVDV Vaccine
Authors: Brock K. V. , McCarty K. , Hartland R.
Published: February 2023

Bovine viral diarrhea virus (BVDV) is a continual concern to the cattle industry. Infection with BVDV may result in either acute disease or persistently infected, asymptomatic carriers. Clinical signs of acute disease include depression, anorexia, reproductive failure, respiratory and gastrointestinal disease in cattle. Acute BVDV infection of pregnant cattle at 30-150 days of gestation may result in calves that are persistently infected (PI). Due to intermittent shedding of virus, these calves pose a continual threat to other cattle. In addition, calves may be at risk for superinfection with a different strain of BVDV, resulting in high mortality. The objective of this study was to evaluate the efficacy of a BVDV Type I modified-live virus (MLV) vaccine to protect against the development of persistently infected calves following a homologous Type 2 challenge of heifers.
Bovine Viral Diarrhea Viruses (BVDV) in the Feedlot
Authors: Fulton R. W. , Hessman B. , Johnson B. J. , Ridpath J. F. , Saliki J. T. , Burge L. J. , Confer A. W. , Payton M. E.
Published: February 2023

Bovine viral diarrhea viruses (BVDV) represent significant pathogens for cattle. The BVDV affect several organ systems; however, the respiratory tract and fetal infections receive critical attention based on disease impact and potential for reservoirs/transmission. BVDV may cause primary infection of the respiratory tract and also serve to predispose the infected bovine to bacterial pathogens such as Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Archanobacterium pyogenes and Mycoplasma spp. Calves infected in utero and born persistently infected (PI) are important reservoirs of infection as they are life-long shedders of virus to susceptible cattle. Respiratory diseases in the feedlot are significant based on morbidity mortality and economic losses. Detection and removal of PI cattle could potentially lessen the economic effect of BVDV in the feedlot. Also, current BVDV control programs utilize vaccines in the US, primarily those containing BVDV1a and BVDV2a strains. Research at our institution has shown that the BVDV1b subgenotype is the major BVDV strain in our diagnostic laboratory accessions. The purpose of this study was three-fold: (1) determine prevalence of PI cattle entering a feedlot; (2) to utilize and compare various diagnostic tests to identify PI cattle; and (3) to determine the distribution of the BVDV1a, BVDV1b and BVDV2a subgenotypes in PI cattle entering the feedlot.
Moraxella bovis and Branhamella ovis and the Occurrence of Pinkeye in Beef Calves
Authors: O'Connor A. M. , Kinyon J. , Whipple A. E. , Reecy J.
Published: February 2023

This study examined the association between Moraxella bovis (M. bovis) and Branhamella ovis (B. ovis) and pinkeye in beef calves.
Summer Externship Program in Food Animal Medicine, Food Safety and Veterinary Public Health (FAME)
Authors: Nydam D. V. , Edmondson K. , Schukken Y. H. , Warnick Lorin
Published: February 2023

Though veterinarians play a vital role in producing an abundant, affordable and safe food supply, fewer veterinarians entering the profession are interested in this aspect of work. Our goal is to attract and train qualified professionals in these areas through experiential learning and real-world problem solving early in their training.
Now That I've Got My Ultrasound, How Do I Pay For It?
Authors: Tabor Elizabeth H.
Published: February 2023

The purpose of this article is to evaluate costs associated with purchasing an ultrasound, and also to consider some applications in a mixed animal practice that may help offset those costs and serve as a lucrative profit center for the clinic.
Dealing with Downers
Authors: Reynolds Jim
Published: February 2023

"Down cattle" are non-ambulatory cattle that cannot stand or walk without assistance. Down cattle present welfare, food safety and economic problems to the cattle industry. Decisions must be made quickly to either care for non-ambulatory livestock properly or to humanely euthanize them. USDA estimated that approximately 200,000 down cattle were presented to slaughter facilities in the US in 2003, and that almost 5% of dairy cattle became non-ambulatory in 2005. Causes are injuries related to dystocia, infectious diseases (toxic mastitis, toxic metritis, lymphoma, peritonitis, septicemia) and metabolic disorders (hypocalcemia, hypomagnesmia, hypophosphatemia, hypokalemia, acidosis). If the animal is suffering and the pain or distress cannot be controlled or is not likely to be controlled quickly, the animal should be euthanized. Treatment includes nursing care that provides comfortable bedding, shelter, food and water, and protection from other cattle and wildlife as well as medical care. Down cattle can be moved on sleds, belts or carefully in tractor buckets, but should not be dragged except in emergency situations. Non-ambulatory cattle cannot be left without water, feed and shelter. Public health issues involve increasing pathogen loads (salmonella, E. coli, and Bovine Spongiform Encephalopathy (BSE)) and tissue residues at slaughter. Current USDA rules curtail the slaughter of down cattle in the US. Economic costs relate to replacement, treatment and nursing care, and potential effects on milk and meat markets (consumer acceptance); 77% of consumers polled replied that they found it unacceptable that downed animals were used for food.
Prudent Use of Pain Relief in Food Animals
Authors: Navarre Christine B.
Published: February 2023

Relief of both acute and chronic pain in animals is an important part of the practice of veterinary medicine. Human pain medications are frequently used in small animal and equine practice. However, food animal practitioners must follow the Animal Medicinal Drug Use Clarification Act (AMDUCA), which puts restraints on the use of analgesics for pain management in food animals. This paper discusses the use of systemic pharmacologic agents for pain. management in cattle, with an emphasis on nonsteroidal anti-inflammatory drugs (NSAIDs). Local anesthetic techniques for pain management are discussed in "Numbirig-Nose to Tail".
Numbing - Nose to Tail
Authors: Navarre Christine B.
Published: February 2023

In this paper, local anesthetic techniques for the most common surgical and medical conditions will be described. These include eye surgery, dehorning, castration, teat surgery, surgery of the foot and epidural anesthesia.
Strategies for the Successful Implementation of Sex Sorted Semen for Beef Females
Authors: Stroud Brad
Published: February 2023

The ability to predetermine the sex of offspring has tremendous managerial and economic implications in the beef cattle industry. With a world population close to seven billion, there is a growing need to produce more beef via the more muscle laden male. In commercial dairy cattle, the situation is just the opposite: the male is an unwanted by-product of breeding for female replacements.

Rabbit sperm was first stained and sorted in 1989, and within a decade the technology was improved through use of high speed flow cytometric sorting of DNA stained sperm. Sorting of bovine sperm has been available for the bovine industry in the US since 2003. The demand is high, but there are significant differences in how sorted sperm is processed before freezing compared to traditional non-sorted sperm. Also, the sorted sperm is packaged differently than traditional non-sorted sperm, which creates handling issues during shipping and thawing samples in the field. These differences have a significant effect on the conception rates of inseminated females. There are many management considerations on the farm or ranch that must be taken into account before a veterinary practitioner recommends sex sorted frozen semen to his clients.
Thoughts on Biosecurity and Biocontainment in Beef Cow-Calf Herds
Authors: Grotelueschen Dale M.
Published: February 2023

Biosecurity and biocontainment plans designed by veterinary practitioners for beef cow-calf operations offer promise for increasingly effective health programs. Individualized utilization of practical methods to eliminate or control pathogen exposure in combination with increased herd immunity engages the operation in health programs that effectively reduce risk for health related losses and increase economic returns to the enterprise. Biosecurity and biocontainment principles address elimination of the agent or agents, prevention of contacts that result in transmission of an agent or agents, and increasing animal resistance to disease.

Changes and trends in the beef industry suggest these concepts are becoming more applicable, practical and potentially of more value. Biosecurity and biocontainment concepts are being further developed. Additionally, more tools, such as diagnostic tests and epidemiological information, are available.

Education and changes in how beef producers address disease control will allow implementation of biosecurity and biocontainment concepts across the industry. Proactive veterinary profession leadership is required for the most successful implementation.
Therapy of Claw Diseases
Authors: Guard Charles
Published: February 2023

The usual treatment of infectious causes of lameness is parenteral antibiotics for foot rot and topical antibiotics and disinfectants for the dermatitides. There continue to be cases of drug resistant foot rot that mostly respond to tylosin when other routine antibiotics fail. Tetracycline powder, oxytetracycline liquid, and a variety of acid or metal salt disinfectants are used successfully to treat digital dermatitis. Greater opportunities for veterinary involvement in lame cow care exist in surgical management of deep sepsis of the digit. Description of claw amputation, simple arthrodesis, navicular resection and arthrodesis, and flexor tendon resection illustrate that there are several field surgical procedures that can be offered for severely lame cows. The outcome for a group of cows from our client farms that received these surgical procedures, without randomization, showed that recovery was better for the arthrodesis procedures than for amputation. Current information on the pathogenesis of digital diseases is included with the discussion of treatment options.
Dual Roles of Cow Comfort in Dairy Herd Lameness Dynamics
Authors: Cook Nigel B.
Published: February 2023

This article describes the dual roles of cow comfort in herd lameness dynamics - interacting with trigger factors to ensure that cows 'get lame' and interacting with the cow once she is lame to ensure that she 'stays lame'. Duration of daily standing activity, the surface that the cow is standing on, and hygiene of that surface are principal components of cow comfort that need to be addressed if we are to break the cycle of 'get lame- stay lame'.
Post-breeding Treatments to lmprove Fertility in Lactating Dairy Cows
Authors: Sterry R. A. , Welle M. L. , Fricke P. M.
Published: February 2023

Lactating Holstein cows were assigned randomly to treatments to improve fertility after first postpartum timed artificial insemination (TAI). In Experiment 1, cows received no treatment (C; n = 223); a CIDR insert from five to 12 days after TAI (CIDR; n = 218); or 100 μg of genadotropin releasing hormone (GnRH) five days after TAI (G5; n = 227). In Experiment 2, cows received C (n = 160), G5 (n = 159), or treatment with 100 μg of GnRH seven days after TAI (G7; n = 163). Although treatment did not affect fertility, when data were combined to compare C (n = 383) and G5 (n = 386) treatments, pregnancies per AI (P/AI) tended to be greater for G5 (49.1 %) than C (45.8 %) cows, and this effect resulted from a GnRH treatment by cyclicity status interaction in which P/AI for anovular cows receiving G5 was greater than that for anovular C cows (45.5 vs. 31.1%). In conclusion, treatment with CIDR inserts after TAI had no effect on fertility, whereas treatment with GnRH five days after TAI improved fertility for anovular, but not for cycling cows.
Client Education
Authors: Czeck Melissa
Published: February 2023

Client education has been practiced in small animal medicine by both veterinarians and technicians for some time and is commonplace. However client education in large animal medicine especially in the cattle industry is not as common and is traditionally done by the veterinarian. Using technicians to educate producers is a management tool that veterinarians are starting to utilize.

As a technician you need to know your limitations both personally and legally. Use a teaching style that best suits you and works for the producer. Using continuing education to educate you both on teaching skills and keeping up on industry trends will help the veterinarian and technician feel more comfortable. Educating producers may be done one on one or in a group, each having benefits according to the situation. Large numbers of people can be reached by producer meetings, peer group sessions, newsletters or websites. One on one session give more personal attention and may be necessary in topics of sensitive issues or with a person who can not learn in a group setting.

Educating clients can be profitable for both the clinic and the farm if done correctly. Using the talents of educated technicians to provide client education will free up time for the veterinarian and increase technician revenue all while benefiting the producer.
Profitability of Producers Who Purchase Beef Cows vs. Those Who Raise Replacements
Authors: Robbe-Austerman S. , Strohbehn D. R.
Published: February 2023

Because the cow-calf sector of the beef industry is mature, average sale price (including high profit and low profit years) hovers around the average cost of production. For cow-calf operations to maintain profitability, producers must either command a higher price or produce calves at below average cost. With the exception of the seed stock sector, calves are usually considered a commodity product; consequently, focusing on producing calves at below average cost is generally more profitable. Comments are often made that it is cheaper to purchase replacements rather than raise heifers. Our objective was to evaluate the profitability and overall production cost of producers who purchase cows compared to producers raising replacement females.
Association between Hoof Lesions and Milk Production in Ontario Dairy Cows
Authors: Cramer Gerard , Lissemore Kerry , Kelton Dave , Guard Chuck , Leslie Ken
Published: February 2023

To preserve and improve the perception of the dairy industry among consumers, there is a need to identify and act upon animal welfare concerns. Lameness is the dairy industry's most visible animal welfare concern. Unfortunately, dairy producers and practitioners often underestimate the level and impact of lameness and hoof lesions on their farm. The impact of lameness and hoof lesions on milk production in North America has not been widely evaluated across a wide number of herds. The objective of this project was to determine the association between infectious and non-infectious hoof lesions and 305-day milk production in dairy cows.
Association between Hoof Lesions and Culling Risk in Ontario Dairy Cows
Authors: Cramer Gerard , Lissemore Kerry , Kelton Dave , Guard Chuck , Leslie Ken
Published: February 2023

Lameness is one of the most important issues facing the dairy industry, both in terms of production costs and consumer perception of dairy cow welfare. One way that lameness and hoof lesions reduce the productivity of dairy cattle is by decreasing longevity. Within the dairy industry, there is widespread concern about the longevity of today's dairy cow. Considering the high prevalence of lameness and hoof lesions, it is surprising that the association between hoof lesions and culling has not been widely evaluated. The objective of this project was to determine the association between infectious and non-infectious hoof lesions and culling risk in dairy cows.
Factors Associated with ELISA S/P Ratio Scores for Paratuberculosis in an Angus-Brahman Multibreed Herd of Beef Cattle
Authors: Elzo M. A. , Rae D. O. , Lanhart S. E. , Wasdin J. G. , Dixon W. P. , Jones J. L.
Published: February 2023

Dam and calf genetic and environmental factors were evaluated for their association with enzyme-linked immunosorbent assay (ELISA) s/p ratio scores for paratuberculosis in a multibreed beef cattle population.