bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Long-Term Progestin-Based Estrous Synchronization Protocols in Beef Cows and Heifers
Authors: Powell J. G. , Lester T. D. , Rowe M. P. , Williams C. L. , Rorie R. W.
Published: February 2023

Synchronization protocols utilizing a 14-day pre-treatment with exogenous progestins prior to gonadotropin releasing hormone (GnRH), and prostaglandin (PG) treatments have been shown to be effective for estrous synchronization in beef cows and heifers. However, beef producers are reluctant to incorporate estrous synchronization and artificial insemination (AI) into their operations. This may be due to the time and labor required for these procedures. Although effective, the progestin-select synch protocol described above can require 33 days to complete. Previous studies in our lab indicate that reducing the time between progestin (CIDR) removal and GnRH dosing from 12 to two days shortens the protocol by 10 days without loss of effectiveness. The objective of our current experiment was to compare the effectiveness of melengestrol acetate (MGA) with CIDR progesterone inserts in an estrous synchronization protocol, where the interval from progestin removal to GnRH dosing was two days.
Effects of Spaying on Average Daily Gain in Implanted Heifers on Pasture
Authors: Schunicht O. C. , Hannon S. J. , Vogstad A. R. , Booker C. W.
Published: February 2023

Pasture grazing of beef feeder cattle destined for subsequent grain-fed feedlot production and slaughter can be a cost-effective production approach for regions with large areas of available pasture, as opposed to dry lot production programs. However, due to reproductive cycling, rates of gain (and presumably grass utilization) for heifers on pasture are lower than for steers. Spaying heifers has been identified as a potential way to improve rates of gain in grazing heifers. The purpose ofthis study was to describe the effects of spaying on rate of gain and health of heifers on pasture in western Canada.
Factors that Influence Resting Time as an Indicator of Cow Comfort in Lactating Dairy Cows
Authors: Villarroel A. , Krahn B. J.
Published: February 2023

Resting time is commonly accepted as an indicator of cow comfort. Current knowledge establishes that cows need to rest as much as possible to produce milk at their genetic potential. In order to evaluate the best housing and management strategies to maximize cow comfort, it is necessary to first establish factors that influence resting time in lactating dairy cattle and determine which of those are manageable.
Veterinary technicians
Authors: Wagner Sarah
Published: February 2023

Employing credentialed veterinary technicians as part of the veterinary medical team enables veterinarians to use their time and skills to make diagnoses, develop prognoses, prescribe treatments, and perform surgeries, while delegating other tasks that require skill and knowledge to the veterinary technician. Practices that employ and properly leverage veterinary technicians can see benefits in several areas, including client services, time management, and profitability.
Case-based studies of infertility in bulls
Authors: Barth A. D.
Published: February 2023

The primary purpose of analysis of the spermiogram is to form an opinion on a bull's potential fertility. When spermiograms are abnormal, often a prognosis for recovery to normal sperm production is also a consideration. Semen quality can change quite rapidly for the better or worse depending on whether a bull is suffering from, or just recovering from, a process detrimental to spermatogenesis. Therefore, the spermiogram must be interpreted in light of the bull's history, the results of the physical examination, and in some cases the semen traits of volume and concentration. Some sperm defects appear to have a genetic basis and knowledge of recessive conditions, or genetic predispositions, will also help to decide on a course of action when abnormal spermiograms are encountered. Cases highlighted in this presentation demonstrate some examples of interpretation of abnormal spermiograms.
Cattle market update
Authors: Dunford Anne
Published: February 2023

Cattle markets in North America were already showing signs of tight supplies long before the 2011 and then 2012 drought occurred in the US. In many parts of cattle producing areas in the US supplies have been tightened even further as we head into 2013. In Canada, after five years of downsizing post-ESE, the beef herd appears to be poised to see growth through heifer retention. Contrary to the US, western Canada has seen two fairly good years in terms of moisture for grass and forage production - critical to growing the herd. But higher grain prices in 2012 are having impacts on both sides of the border as higher costs have meant cattle feeding losses for much of this year. Margin operators have been caught between fewer cattle supplies/higher cattle prices and record high costs. A key concern in both the cattle feeding and cattle packing industries is that there is too much capacity chasing these fewer cattle supplies. Add to that the global economy, which has been fragile at best, and you get a very volatile environment ranging from: tight supplies = higher prices; all the way to: cautious consumers = competitive protein markets both here and abroad. Record high cattle and beef prices would have historically meant great profits but with today's cost structure (namely grains), it's not quite that simple.
Diagnosis and control of small ruminant abortion
Authors: Menzies Paula I.
Published: February 2023

Abortion, as either an outbreak or enzootic disease issue, is an important production-limiting disease of sheep and goats. This article describes how to approach diagnosis and management of the more common causes of abortion in the US and Canada, i.e. Campylobacter fetus subspecies fetus, Campylobacter jejuni, Chlamydophila abortus, Toxoplasma gondii, and iodine deficiency goiter. It also gives an overview of the less-common causes of abortion in sheep and goats. Zoonotic implications of the various disease agents will also be addressed, as well as how to reduce risk to humans. Coxiella burnetii is covered in a separate lecture.
Preliminary program outcomes from the Atlantic Johne's Disease Initiative
Authors: MacDonald-Phillips Karen , Keefe Greg , McKenna Shawn
Published: February 2023

Johne's disease is an incurable, chronic, infectious enteritis of ruminants. It has been identified as one of the top animal health priorities for the Canadian dairy industry by the Dairy Farmers of Canada. As such, the Atlantic Johne's Disease Initiative (AJDI) was launched as a voluntary, long-term farm strategy. The overall objective of the program is to reduce the spread, prevalence, and overall impact of J ohne's disease in Atlantic Canada through education, strategic testing, and management programs. This report outlines program implementation statistics, preliminary prevalence data, and primary management plan recommendations.
Risk factors for Prototheca mastitis on Ontario dairy farms
Authors: Pieper Laura , Godkin Ann , Kelton David
Published: February 2023

Prototheca spp are unicellular, colorless algae that can cause incurable mastitis in dairy cows. Prototheca mastitis has been reported in many regions including North and South America, Europe, and Asia. Mastitis caused by these algae is rare, and knowledge about the risk factors for Prototheca mastitis is lacking. Anecdotal reports have suggested that improper milking hygiene, unsanitary environmental conditions, and the use of intramammary antimicrobial treatment may influence the development of the disease. However, scientific evidence in support of these risk factors has often been weak because of very small sample sizes or lack of comparison groups. In Ontario, mastitis caused by Prototheca spp appears to be an emerging disease, which leaves veterinarians and farmers with many questions and challenges. The aim of this case-control study was to formally assess herd-level risk factors for Prototheca mastitis on Ontario dairy farms.
Comparison of 5-day versus 7-day CIDR CO-Synch protocol in crossbred commercial beef cows
Authors: Holland S. C. , Whittier D. W. , Clark S. G. , Currin J. F. , Schramm H. H. , Kasimanickam R. K.
Published: February 2023

Artificial insemination (Al) is used by only approximately 10% of beef producers in the United States. Estrus synchronization and timed AI (TAI) minimize time and labor relative to heat detection; however, these factors are still a big constraint for producers. In literature, conception rates following TAI using various synchronization protocols range from approximately 30 to 65%. One commonly used protocol is CO-Synch, which consists of a shot of GnRH on day 0, a shot of PGF2a on day 7, and another shot of GnRH at breeding (72 hours after PGF2a). Several variations of CO-Synch that minimize labor but maximize conception rate have been identified, and comparisons are ongoing. Although the 7-day CIDR CO-Synch has been used with relative success, recent studies have suggested that a similar 5-day protocol may result in improved conception rates. Although the 5-day protocol may yield higher conception rates, especially in heifers, it also may require a second dose of PGF2a given six hours after CIDR removal, which will significantly increase time and labor required. Several recent studies have compared the 5-day to the 7-day CIDR CO-Synch, but cow numbers were too low to detect small differences. Further comparison of these two protocols is necessary to determine the benefit versus the cost of the 5-day CIDR CO-Synch.
Isolation of Mycobacterium avium ssp paratuberculosis from the saliva of cattle
Authors: Sorge U. S. , Kurnick S. , Sreevatsan S.
Published: February 2023

Johne's disease can be an economically devastating disease on dairy farms. Current risk assessment (RA)-based control programs use best management practices to prevent the transmission of the causative pathogen, Mycobacterium avium subsp paratuberculosis (MAP), between animals. Most effort is focused on the fecal-oral route of transmission between infectious dams and calves. Because MAP has been isolated from water troughs, the objective of this pilot study was to determine whether MAP can be detected in the saliva (a previously overlooked route of transmission) of infected cattle.
Comparison of serum concentrations and duration of BVDV 1, BVDV 2, BHV-1, BRSV, and PI3 virus-neutralizing antibodies in calves fed maternal colostrum or a colostrum replacer at birth
Authors: Chamorro M. F. , Walz P. H. , Haines D. M. , Passler T. , Earleywine T. , Givens M. D.
Published: February 2023

Providing newborn calves with high concentrations of neutralizing antibodies through colostrum is a key management strategy for the reduction of respiratory disease caused by BVDV, BHV-1, BRSV, and PI3 in young calves. When maternally-derived immunity decays, calves become susceptible to acute viral infection and disease. Duration of maternally-derived immunity is dependent on the amount of neutralizing antibodies absorbed from colostrum. Feeding a commercial colostrum replacer is an alternative to provide passive immunity to neonatal calves when availability of maternal colostrum is compromised. The ability of colostrum replacers to provide neonatal calves with an adequate concentration and duration of specific virus-neutralizing antibodies against common respiratory viruses has not been described. The objective of this study was to compare the total serum concentration and duration of BVDV, BHV-1, BRSV and PI3 virus neutralizing antibodies in calves fed maternal colostrum (MC) or a commercial colostrum replacer (CR) at birth.
Otitis media and interna in dairy calves
Authors: Gosselin V. Bernier , Fecteau G. , Francoz D. , Desrochers A. , Nichols S. , Babkine M.
Published: February 2023

Otitis media is a common disease in calves. Although its prevalence has not yet been established, it is probably underestimated. Clinical signs of otitis media include a dropped ear caused by facial paralysis, head tilt, and purulent auricular discharge. Prognosis is variable. Poor response to treatment has been reported to be associated with chronicity, intracranial invasion, multisystemic disease and etiological agent. Recently, Mycoplasma spp has been reported as a common cause of otitis in calves. The objective of this retrospective study was to review the epidemiological data, clinical findings, laboratory data, medical imaging results, and outcomes of dairy calves diagnosed with otitis media or interna that were referred to the Centre Hospitalier Universitaire Vétérinaire (CHUV) of the Université de Montréal.
Bovine coronaviruses from the respiratory tract
Authors: Fulton R. W. , Ridpath J. F. , Burge L. J.
Published: February 2023

Bovine coronaviruses (BoCV) have been associated with bovine respiratory diseases (BRD) in cattle pulled for treatment in feedlots and from healthy cattle in the US with BoCV identified by virus isolation from nasal swab and bronchoalveolar lavage (BAL) samples, and also by seroconversions for the detection of active infections. Bovine coronaviruses have been identified in pneumonic lungs from field cases, often in combination with other viruses and bacteria including Mycoplasma spp. Experimentally, BoCV infections have caused respiratory tract lesions. It has been suggested there is a dual tropism of BoCV for the respiratory and enteric tracts. Historically, BoCV was associated with neonatal enteric disease and adult winter dysentery. Respiratory isolates were identified later and focused on post-weaning cattle entering feedlots. Control measures are limited. There are USDA-licensed killed and modified live virus (MLV) vaccines for BoCV; however, these are for control of the enteric disease in cattle. There are no USDA-licensed vaccines for control of BoCV associated BRD in cattle. The purpose of the study was to compare BoCVisolates from the respiratory tract of cattle in Oklahoma to reference respiratory tract and enteric strains via antigenic and genetic procedures.
Biosecurity practices of midwestern veterinarians in food animal and mixed animal practices
Authors: Engelken T. J. , Bickett-Weddle D. , Wang C.
Published: February 2023

Biosecurity practices are designed to prevent the spread of disease, yet implementation of those practices varies greatly among animal owners and veterinarians. Veterinarians working in food animal and mixed animal practices have a role in the design and implementation of biosecurity protocols for their clients and are responsible for minimizing their potential to act as a disease "fomite" as they move between operations. The objective of this project was to survey Midwestern veterinary practitioners to determine their current implementation of biosecurity and infection control practices.
Effects of prepartum grouping strategy on immune, metabolic, health, reproductive, and productive parameters of dairy cows
Authors: Silva P. R. B. , Moraes J. G. N. , Mendonça L. G. D. , Scanavez A. A. , Endres M. I. , Chebel R. C.
Published: February 2023

Cows are social animals and as such are highly susceptible to social interactions and hierarchical order. Situations of limited space or access to feed and frequent regrouping during the prepartum period are expected to exacerbate aggressive and submissive behaviors. In studies conducted with a small number of cows per pen, cows had reduced feeding time, greater rate of displacement from the feed bunk and stalls, and reduced milk yield up to three to 14 days after regrouping. Therefore, weekly regrouping of prepartum dairy cows is expected to result in exposure of these cows to a continuous state of social unrest and stress during the most critical time of their lives. This abstract discusses results from a study in a commercial dairy that evaluated an 'All-In-All-Out' (AIAO) approach to regrouping prepartum cows.
Performance of feedlot Nellore cattle fed with rations containing different corn genotypes
Authors: Cunha G. E. , Mizubuti I. Y. , Sestari B. B. , Gomes R. C. , Pereira E. S. , Ribeiro E. L. A.
Published: February 2023

Of the world's maize production, 70% to 85% is used for animal feed and represents a high-quality energy source. The main corn genotypes are flint corn (high vitreous endosperm), semi-flint corn (medium vitreous endosperm), and semi-dent corn (low vitreous endosperm); as the vitreous in the grain increases, starch degradation decreases. The whole grain and intact matrix protein of corn are resistant to digestion by ruminants because rumen bacteria cannot adhere to them. Some studies have shown that starch degradation is better for corn with low vitreous endosperm; however, in Brazil, most of maize produced is flint corn (high vitreous endosperm). Most farmers use corn grain that is ground and incorporated into the concentrate ration for ruminant feeds without consideration of corn genotype or particle size, which influence rumen fermentation, microbial protein yield, and feed efficiency. This trial was conducted to evaluate the performance of beef feedlot cattle that received rations containing different corn genotypes.
On-farm study of mastitis-associated bacteria recovered from five bedding materials
Authors: Keefe Greg , Nekouei Omid , Dohoo Ian , Anderson Don , Yu Jenny
Published: February 2023

Mastitis remains the most costly infectious disease affecting dairy cattle. Bacterial populations in materials used as bedding in stalls for lactating cows has been correlated with teat-end exposure to mastitis pathogens and rates of clinical mastitis. Various bedding materials have different inherent ability to promote mastitis pathogen growth. In Atlantic Canada, access to quality bedding materials is a challenge. Milk 2020, a research agency of the New Brunswick dairy industry, sponsored this project to measure the growth patterns of mastitis-associated bacteria in different bedding materials under field conditions.
Optimization of in vitro gowth conditions and DNA extraction from Treponema phagedenis isolated from bovine digital dermatitis lesions
Authors: Krull A. , Plummer P.
Published: February 2023

Bovine digital dermatitis is a leading cause of lameness in the US dairy industry, and it also represents a significant welfare issue. Our group and others have demonstrated that, along with a number of other organisms, Treponema spp can be cultured from a large percentage of digital dermatitis lesions. As part of our ongoing effort to better understand the role that Treponema spp plays in this disease process, we are using a combination of culture-dependent and independent methods to better understand the physiology and metabolism of these bacteria. Treponema spp are fastidious and their growth in broth media has traditionally been difficult; thus; hindering the ability to grow sufficient organisms for DNA purification to be used in downstream sequencing or genetic modification. This study details the systematic evaluation of different culture conditions on the growth and replication of T. phagedenis isolated from digital dermatitis lesions of cattle.
Reasonable expectations for antibiotics in feedyards
Authors: Apley Michael D. , Dedonder Keith D.
Published: February 2023

Use of the Number Needed to Treat (NNT) statistic allows for evaluation and communication of reasonable treatment outcome expectations in populations. The NNT value for a treatment estimates the number of animals which need to be treated in order to make an outcome difference in 1 animal. Evaluation of negative control studies for bovine respiratory disease suggests that the NNT values in high-risk calves for creating a treatment success, prevention of a mortality, and prevention of a clinical case through treatment for control of BRD are 2, 7, and 5, respectively. These values will obviously vary significantly in different clinical situations, but give reasonable expectations for the use of multiple antimicrobials in different groups of cattle over time.
dairy producer's perspective on managing drug and antibiotic use in dairy animals
Authors: Weaver Leon D.
Published: February 2023

This presentation outlines how three large dairy farms with common ownership implemented programs to make standardized animal care and treatment decisions. The approach used on these dairies may offer concepts useful to others seeking to enhance their involvements and outcomes in these areas. Central to the effort on these dairies was identifying the one specific owner, partner or manager who would make the final policy decisions as well as the veterinarian(s) authorized to negotiate final drug and treatment policy and protocols with the owner. These dairies established an Animal Care and Health Policy Group to lead this effort. This group comprised of the owner, veterinarian, and Dairy Herd Managers meets at least monthly to discuss, establish and modify animal care and treatment policy, protocols and procedures. The policy group often includes or consults with others such as veterinarians representing pharmaceutical companies, drug vendors and milk inspectors in both policy planning and staff training activities. Monthly meetings are scheduled at each dairy to train animal care managers and their associated staff. Veterinarians involved in these planning and training activities have developed a portfolio of technical services and communication and language skills that they can provide more expertly and more conveniently than others.
From pasture to package
Authors: Hatcher Charles W.
Published: February 2023

The dairy industry in the United States has undergone significant structural change in the last 50 years. In Williamson County, Tennessee, which is my home county, there were over 500 dairies in the county during the 1950s. Now there are 4, and the Hatcher Family Dairy is one of those 4 remaining dairies.

This is the story of how our farm family reached for the retail dollar to save the dairy.
Milk bacteriology
Authors: Erskine R. J.
Published: February 2023

Bacteriological culture of milk provides fundamental information to veterinarians, their support staff, and dairy producers who want to improve milk quality on dairy farms. In-clinic or on-farm culture cannot achieve the degree of sophistication of an accredited diagnostic laboratory. Nonetheless, non-diagnostic laboratory culture of milk samples can help identify opportunities in farm management, as well as therapeutic decisions. The fundamentals of milk bacteriology are not difficult, and numerous resources are available to help veterinary personnel establish basic milk bacteriology laboratories. Care should be taken to avoid common pitfalls in interpretation and application of the culture results.
Economic considerations for subclinical ketosis in lactating dairy cattle
Authors: Gohary K. G. , LeBlanc S. J. , Lissemore K. D. , Von Massow M. , Overton M. W.
Published: February 2023

Milk production and reproductive performance can decrease as a result of hyperketonemia in lactating dairy cows. In addition, cows with hyperketonemia are at higher risk of developing a variety of diseases including displaced abomasum, metritis, retained placenta, and clinical ketosis, and are more likely to be culled. The negative impact of hyperketonemia can be observed at both the individual-cow and herd levels. As a result, significant economic losses might be encountered in dairy herds with a high incidence of hyperketonemia.
Association of bovine leukemia virus and Mycobacterium avium subsp paratuberculosis with shedding of Shiga toxin-producing Escherichia coli (STEC)
Authors: Venegas-Vargas C. , Bartlett P. , Coussens P. , Manning S. D. , Grooms D.
Published: February 2023

Cattle are a reservoir of Shiga toxin-producing Escherichia coli (STEC), which is an important cause of foodborne illness and hemolytic uremic syndrome (HUS) in children. Bovine leukemia virus (BLV) is a retrovirus that causes enzootic bovine leukosis. Most animals infected with BLV never develop clinical signs, but 30% of BLV carriers will develop a persistent lymphocytosis, and< 5% will develop malignant lymphosarcoma. Johnes' disease (JD) is caused by Mycobacterium avium subsp paratuberculosis (MAP), and cattle generally become infected with MAP at a very early age ( < 30 days old), although clinical disease does not typically manifest itself until 3-5 years of age. Recent studies have estimated the herd prevalence of BLV and JD in Michigan dairy herds to be approximately 85% and 50%, respectively. Both diseases are chronic in nature and can have a negative impact on the health and productivity of cattle from both clinical and subclinical effects. Because of their chronic and potentially debilitating nature, secondary health issues are often associated with BLV and JD. Our hypothesis was that cattle infected with BLV and JD were more likely to shed STEC than were uninfected cattle. Our rationale for this hypothesis was that BLV affects the immune system of cattle, which might favor the colonization and shedding of STEC. In the case of JD, the alteration of normal intestinal function and structure could potentially favor the colonization and shedding of STEC in infected cattle. Our objective was to determine whether cattle that test positive for JD and BLV could be a potential target population for the implementation of control strategies to reduce STEC contamination in the human food chain.
Evaluation of the API® 20 Strep system for identification of Lactococcus lactis subspecies lactis isolated from bovine milk samples
Authors: Barrett M. M. , Nydam D. V. , Carter B. Moslock , Charter M. E. , Burnett D. , Adamchick J.
Published: February 2023

Environmental streptococci and streptococci-like bacteria, including Lactococcus lactis ssp lactis, account for approximately 40% of clinical mastitis cases in cows. Recently, Lactococcus lactis ssp lactis was associated with intramammary infections on several New York farms. Although Lactococcus lactis ssp lactis has been isolated from the bovine udder, its importance as a mastitis pathogen is unclear because of misidentification by use of traditional bacterial identification techniques. Molecular identification has improved correct identification of bacterial pathogens, but it is expensive for the clinical practitioner. In this study, the sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), and kappa (k) of the API 20 Strep system for identification of Lactococcus lactis ssp lactis were assessed by the use of molecular identification results as the standard.
Use of thoracic ultrasonography for the evaluation of lung pathology in beef cattle with acute bovine respiratory disease
Authors: Rademacher Ryan , Buczinski Sébastien , Edmonds Matthew , Tripp Holt , Johnson Edward
Published: February 2023

Bovine respiratory disease (BRD) is the most economically important disease of feedlot cattle. To enhance management of individual feedlot cattle with BRD there is a need to better determine the extent and duration of lung pathology on a real-time basis. Development of an objective ultrasound (U/S) scoring system that allows for better interpretation of the disease pathogenesis may improve individual case management. Although the peer-reviewed literature contains multiple reports on the use of thoracic U/S for the evaluation of BRD in dairy cattle, reports of its use in feedlot cattle are limited. The purpose of this study was to describe the use of thoracic U/S for the evaluation of BRD in feedlot cattle.
Effect of surgical castration at different stages of maturity with or without analgesia on growth performance and acute-phase response
Authors: Powell J. G. , Hughes H. D. , Richeson J. T. , Kegley E. B. , Burdick Sanchez N. C. , Carroll J. A.
Published: February 2023

Although castration is a commonly practiced management procedure, it causes pain and stress that can temporarily reduce performance. Currently, there is no approved medication for analgesia in cattle. Meloxicam is a non-steroidal anti-inflammatory drug (NSAID) approved by the FDA for analgesic use in companion animal species. The objective of this study was to determine whether surgical castration at birth or weaning with or without concurrent analgesia by administration of meloxicam impacts growth performance or the acute-phase response (APR).
Genomic variation in innate immunity and susceptibility to uterine diseases in Holstein cows
Authors: Pinedo P. J. , Galvao K. N. , Seabury C. M.
Published: February 2023

Fertility is crucial for efficient dairy production, and adequate uterine health is a key element that allows for rapid resumption of reproductive function after calving. The challenge of uterine contamination with microorganisms at parturition is unavoidable. Some cows respond to this challenge successfully; however, approximately 20% of cows will develop metritis or clinical endometritis. Subsequently, the prevalence of subclinical endometritis will range from 25% to 75%. Innate immunity provides the first line of defense against infection by eliciting host responses to invading pathogens without requiring prior exposure. This response depends mainly on the action of neutrophils (PMNs) and macrophages with pattern recognition receptors that recognize molecular ligands from microbial species, which then initiate signaling pathways that result in the release of pro-inflammatory cytokines. One important group of receptors is the toll-like receptors (TLR), which regulate the activation of both innate and adaptive immunity. Likewise, the initial defense of the endometrium against invading microbes is dependent on the innate immune system, including initial recognition by host TLR proteins. Genetic selection for increased disease resistance in cattle has been proposed, and current molecular technologies provide the opportunity for exploring genomic variation related to health. We hypothesized that naturally occurring variation within the bovine TLR genes may be associated with differential susceptibility to reproductive diseases in Holstein cattle. The objective of this study was to test for associations between bovine single nucleotide polymorphisms (SNPs) and insertion-deletion (indel) mutations occurring in 7 bovine TLR genes (TLRsl, 2, 4, 5, 6, 9, and 10) that are known to recognize bacterial ligands and uterine diseases in dairy cows including metritis (MET), clinical endometritis (CE), and cytologic endometritis (CYE).
Intra-farm communication about calf health
Authors: Moore D. A. , Sischo W. M. , Davis M. A. , Vanegas J. , Pereira R. , Warnick L.
Published: February 2023

Effective communication within an organization is essential for accomplishing tasks and for job performance and satisfaction. The dairy business is not an exception to this rule, especially as it applies to animal health and the many people responsible for animal care. Because dairy veterinarians work with the consolidating US dairy industry, their understanding of the many layers of management on these larger farms and the communication realities within them are critical to effective implementation of health-care decisions. Of particular concern are drug-use decisions at the calf level.
Application of the Bovine Milk Pregnancy ELISA in beef cows
Authors: Roberts J. N. , Grooms D. L. , Byrem T. M.
Published: February 2023

Pregnancy-associated glycoproteins (PAGs) are produced by binucleate giant cells of the ruminant placenta and secreted into maternal circulation during pregnancy. These proteins can be detected in maternal serum and milk as early as 28 days post-insemination, which makes them a potential target for pregnancy detection, which in turn could provide an alternative management tool for dairy and beef producers. The presence of PA Gs in serum has been used extensively to diagnose bovine pregnancy. More recently, the Bovine Pregnancy ELISA (IDEXX, Westbrook ME) has been used to detect the presence of PAGs in milk. Although the milk ELISA was designed primarily to be a management tool for dairy operations, it has potential for use in beef operations in remote areas where veterinarians are not readily available to perform pregnancy diagnosis and the producer lacks the skill set to collect a blood sample. The objective of this study was to compare the results of the PAG ELISA used on milk and serum to pregnancy diagnosis by transrectal palpation or ultrasound in lactating beef cows with previous artificial inseminations or bull exposure.
Evaluation of behavioral changes in cattle using three-dimensional accelerometers during experimental infection with bovine viral diarrhea virus
Authors: Bayne J. E. , Passler T. , White B. J. , Theurer M. E. , Van Stanten E. , Walz P. H.
Published: February 2023

Bovine respiratory disease (BRD) is a leading cause of morbidity and death in cattle. Timely recognition of sickness before development of irreparable damage to the lungs, which results in substantial economic loss, continues to be difficult. Bovine viral diarrhea virus (BVDV) contributes to the development of BRD. Currently, detection of BRD relies upon subjective assessment of cattle, which is reported to have a low diagnostic sensitivity and specificity because ill cattle alter behavior in the presence of human observers. Efforts to identify BRD and predict its occurrence have used clinicopathologic measures of inflammation, including alterations in inflammatory cells and acute phase proteins, such as haptoglobin. These diagnostics are invasive, expensive, and subject to variability dependent upon the stage of the disease. The need for remote, objective measurement of behavior in ill cattle prompted the development of several technologies capable of real-time collection of various physiologic variables. The objective of this study was to evaluate the behavior of cattle that were experimentally inoculated with a low-virulent strain of BVDV and presumably subclinically infected by the use of 3-D accelerometers. Behavior responses were evaluated in conjunction with traditional markers of inflammation.
Pathogenicity of Bibersteinia trehalosi in cattle
Authors: Hanthorn C. J. , Dewell R. D. , Cooper V. , Plummer P. , Dewell G. A.
Published: February 2023

Bibersteinia trehalosi causes disease in ruminants worldwide, and is associated with pneumonia or septicemia in sheep. Although infection with B. trehalosi is uncommon in cattle, it is a potential pathogen responsible for bovine respiratory disease (BRD). Anecdotal reports of increasing prevalence of B. trehalosi isolated from cattle with severe disease have heightened producer and veterinary awareness.
Effect of adding gut-active carbohydrates to fresh colostrum on passive transfer of immunoglobulin G in Holstein dairy calves
Authors: Brady Matthew Patten , Godden Sandra , Haines Deborah
Published: February 2023

Lower concentrations of coliform bacteria in maternal colostrum (MC) have been associated with enhanced IgG absorption in calves. Mannan-oligosaccharide, a gut active carbohydrate (GAC) derived from yeast cell walls, can adsorb pathogens expressing type-1-fimbriae, which reduces their ability to colonize the gastrointestinal tract. Results of preliminary research suggest that feeding GAC in colostrum enhanced serum IgG concentration in calves. The purpose of this study was to investigate whether addition of a GAC (Bio-MOS®. Alltech, Inc.) to colostrum would increase IgG absorption in newborn calves.
Fecal lipidomic biomarkers in production-related metabolic disease (PRMD)-resistant and susceptible dairy cows
Authors: Roeder B. L. , Boyce T. T. , Olsen R. S. , Cook A. C. , Coutu B. G. , Eggett D. L.
Published: February 2023

Although it is known that the highest incidence for most production-related metabolic diseases (PRMDs; ie, milk fever, fatty liver, ketosis, LDA, mastitis, and infections) occurs within 60 days-in-milk (DIM), PRMD incidence has not been altered by transition diets, dietary CAD, and avoidance of over-conditioning. Economic returns are significantly affected by PRMDs because of altered milk composition or decreased production, conception, life expectancy, and cull value. The risk for PRMD has been correlated with increased serum FFA, NEFA, TG, and PHBA concentrations and hepatic TG-to-glycogen ratio. Regulation of hepatic metabolism is dynamic and can differ between similarly managed transition cows. The difference in fecal carbon stable isotopes (13C/12C ratio, 813C) measured 3 weeks prepartum and at parturition predicted 66% of cows resistant to or at risk for PRMDs in the subsequent lactation, with susceptible cows having a more depleted isotopic signature correlated with mobilizing endogenous lipid and protein stores for maintenance needs. Finding these differences prior to PRMD onset prompted investigation of fecal lipids present at the beginning of the transition period and at parturition. The objectives of this study were to determine the fecal lipid profiles for PRMD-resistant and PMRD-susceptible cows, and to determine if PRMD-susceptible cows have unique fecal lipidome biomarkers.
Field pathology
Authors: Glock Robert D. , Portillo Thomas A.
Published: February 2023

Necropsies are an integral part of health programs in cattle feeding operations. Multiple benefits include better methods of fine tuning prevention and treatment programs. Disease processes are made visible and can be used in the very important process of training cattle handling personnel. Efficient use of time is enhanced by practical necropsy procedures. Guidelines are provided for necropsy interpretation and differential processes. Necropsy tips include use of necropsies to evaluate vaccine effectiveness, evaluation of pneumonias as dynamic processes, recognition of different types of interstitial pneumonias, and clarification of relationships between acidosis and other digestive diseases. Diseases of the central nervous system can be differentiated through necropsy observations supplemented with judicious use of laboratory assistance.
Comparison of a remote early disease identification (REDI) system to metaphylaxis and conventional management for control of bovine respiratory disease in high risk beef calves
Authors: White Brad J. , Goehl Dan R. , Amrine David E.
Published: February 2023

Antimicrobial treatment of an entire cohort on arrival is common when the group is deemed high risk for bovine respiratory disease (BRD). Early and accurate BRD diagnosis could alter population disease dynamics and provide an alternative BRD control method. The research objective was to compare health and performance outcomes of high risk calves managed through conventional means (metaphylaxis and human observation) to cattle managed using a remote, early disease identification (REDI) system.
Predicting prognosis of left displaced abomasal corrective surgery
Authors: Reynen J. L. , LeBlanc S. J. , Kelton D. F. , Duffield T. F.
Published: February 2023

The incidence rate of left displaced abomasum (LDA) in North America is commonly 3 to 7% of calvings. Of these cases, 12 to 17% are culled or die within 30 days of surgery. There have been numerous studies focused on predicting prognosis for right displaced abomasal corrective surgery; however, fewer studies focus on LDA surgeries. These studies tend to measure only a few parameters (i.e. blood analysis) and none focus on concurrent disease or physical exam at diagnosis. Croushore et al (2013) reported that cows that were not ketotic at diagnosis (BHBA<1.2mmol/L) were at 2.5 times greater risk of being culled within 30 days than ketotic cows. Various studies have also demonstrated that elevated aspartate aminotransferase, glutamate dehydrogenase, ornithine carbamoyl transferase, bilirubin, urea, Ca, K, and Mg were associated with an increased risk of unfavorable outcomes. The objective of this research was to determine if patient survival (or culling) within 60 days after surgery could be predicted from the physical exam findings, concurrent disease status, and a biochemical profile from a blood sample obtained at the time of LDA diagnosis.
Comparison of serum progesterone curves in beef heifers during luteolysis after administration of dinoprost in the muscle or the ischiorectal fossa
Authors: Holland S. C. , Clark S. G. , Whittier W. D. , Swecker W. S.
Published: February 2023

Many producers and veterinarians report injection of products in the rear legs or hip due to convenience or lack of access to the neck. Provision of an acceptable injection site that can be accessed from behind the cow for administration of therapeutics may improve compliance and beef products. The authors propose the ischiorectal fossa (IRF), located adjacent to the tailhead and craniomedial to the tuber ischia, as an alternate injection site for products in cattle. A suitable drug to use for proof of concept is Prostaglandin F2α (PGF2α), given that the physiological outcome variable (luteolysis) is detected by a decline in serum progesterone. Colazo et al demonstrated that PGF2α given in the IRF or IM in the neck resulted in similar rates of luteolysis (2002). However, Chebel et al found a difference in time to estrus in beef heifers given a prostaglandin analog either IM in the neck or subcutaneously (2007). The objective of this study was to determine if PGF2α given in the IRF results in luteolysis at a similar time as PGF2α given IM in the neck. Our goal is to provide producers and veterinarians with an alternative to the current practice of harmful injections in the rear legs.
Pre-breeding beef heifer management and season affect mid to late gestation uteroplacental hemodynamics
Authors: Cain A. J. , Lemley C. O. , Walters F. K. , Christiansen D. L. , King E. H. , Hopper R. M.
Published: February 2023

In a well-managed beef herd, heifers should represent the most valuable genetics in the herd and be an improvement on the previous generation of females. Recent economic conditions have brought forth a trend in which heifers are developed in “low input” management scenarios where they typically achieve 50-55% of projected mature body weight at breeding as opposed to the more traditional 65-70%. Seasonal differences in calf performance and heifer reproductive efficiency have also been observed. The uterine environment during gestation is known to have lifelong epigenetic effects on offspring. This is often achieved by imposing suboptimal conditions or nutrition prior to breeding or during gestation, and the effects may be translated to the developing calf by altered patterns of uteroplacental blood flow. Thus, it was hypothesized that low input heifer development protocols resulting in light weight heifers at breeding may cause decreased uteroplacental blood flow during pregnancy compared to traditionally developed females even when nutrition during gestation is equivalent. Furthermore, it was posited that calving season may also alter uteroplacental hemodynamics. Therefore, the objective of the present study was to evaluate the effects of heifer development practices and season on uteroplacental hemodynamics during mid to late gestation of nulliparous beef females.
Pharmacokinetics of hetacillin in dairy cattle following 3X milking
Authors: Lindquist D. A. , Baynes R. E. , Smith G. W.
Published: February 2023

Mastitis remains a critical disease in the dairy industry and the use of intramammary antibiotics plays a critical role in mastitis treatment. Hetacin-K® (Boehringer Ingelheim Vetmedica, Inc) is currently approved as an intramammary antibiotic that is used to treat mastitis in dairy cows. It is approved for once daily intramammary administration and can be used for a total of three days. More and more dairy farms are milking three times per day instead of the traditional two times per day; however, there is very little pharmacokinetic data on the use of intramammary drugs such as Hetacin-K® in a 3X system. The purpose of this study was to determine if once daily intramammary infusion of Hetacin-K® is sufficient to maintain therapeutic drug concentrations in cattle milked three times per day.
Pharmacokinetics and tissue elimination of flunixin in veal calves
Authors: Smith G. W. , Brinson P. D. , Gehring R. , Baynes R. E. , Kissell L. W. , Tell L. A.
Published: February 2023

Currently flunixin is one of the leading violative drug residue found in veal calves. Although it is approved for use in adult cattle, there is not a specific approval for use in calves that are to be processed for veal. However the drug is often used in an extralabel manner as supportive therapy associated with calf diarrhea or pneumonia. Unfortunately pharmacokinetic data regarding the use of flunixin in young calves is not available. Therefore the primary objective of this study was to examine the pharmacokinetics and tissue elimination of flunixin following administration to veal calves.
Comparison of a novel umbilical dip, Super7+™ Navel Dip, to 7% tincture of iodine to desiccate the umbilical remnant in neonatal Holstein dairy calves
Authors: Gard J. A. , Rodning S. P. , Duran S. , Taylor D. R. , Edmondson M. A. , DeGraves F. , Fields B. , Farrell R. , Schnuelle M. L. , Bratcher C. , Justus W.
Published: February 2023

Reduction of naval infections through appropriate management including naval dipping is beneficial to the calf and the producer and is reported to decrease naval infection rates from 20-28% to 5-14%. Obviously, naval dipping is of great importance but obtaining tincture of iodine has become problematic. It has become necessary to develop other products that can be utilized to dry the umbilicus and assist in the prevention of navel infections. Hence, the aim of this study was to evaluate Super7+™ Navel Dip as an alternative to 7% tincture of iodine.
Using chitosan microparticles to prevent metritis in lactating dairy cows
Authors: Daetz R. , Bittar J. H. J. , Santos J. E. P. , Cunha F. , Magalhaes F. , Maeda Y. , Risco C. , Galvao K. N.
Published: February 2023

Metritis, an acute inflammatory disease of multiple layers of the uterine lining with systemic implications, affects 20 to 40% of the postpartum dairy cows and has marked welfare, health, production, reproduction, and economic consequences to the individual animal and the herd. In cows with risk factors such as dystocia, delivery of twin calves, retained placenta (RP) or stillbirth the incidence ranges from 50 to 70%. Traditionally, antibiotics have been used to prevent or treat uterine disease. Ceftiofur hydrochloride is 1 of the 3 approved antibiotics for systemic administration for treatment of metritis in dairy cows, and it is the antibiotic of choice because it does not incur a milk withhold. The Food and Drug Administration, based on the risk to public health, and as an attempt to limit the use of third generation cephalosporins, banned the use of this class of drugs for disease prevention in food animals. Chitosan microparticles (CM) is a polysaccharide derived from chitin found in the exoskeleton of crustaceans, and at a concentration of 0.2%, was found to be as effective as ceftiofur hydrochloride at reducing intrauterine E. coli. The main aim of this study was to investigate whether CM could be used as an alternative to traditional antibiotics for the prevention of metritis in dairy cows.
Using Y chromosome fragment testing to identify potentially sub-fertile beef heifers
Authors: Studstill Matthew , Stewart Lawton , Jones Lee
Published: February 2023

Selecting and developing fertile replacement heifers is essential for reproductive efficiency in beef herds. Fertile heifers that reach puberty and conceive early and calve early in their first calving season are generally more productive and have increased longevity compared to heifers that calve late in their first calving season. Costs of developing heifers through their first breeding season are substantial due to nutritional requirements for growth and maintenance. Recent literature has suggested new genetic technologies that may allow producers to select replacements based on genetic soundness. Genetic testing identified the presence of Y chromosome fragments in pools of infertile cows (McDaneld, Kuehn et al, 2012). Tests such as this could provide cow-calf producers with a convenient and economical tool to select replacement heifers before development costs are incurred. This study investigated the presence of Y chromosome fragments in 3 heifer development programs in Georgia. The goal of this study was to determine the presence of the Y chromosome anomaly in this population of replacement heifers.