bluuebunny/crossref_metadata_2025 huggingface dataset:
Cowslips, the alternative to the foot block
Authors: Blowey Roger
Published: March 2023

In the treatment of bovine digital lameness the practitioner must consider three general areas. These are speed of resolution of the lesion, reduction in pain and improvement in the welfare of the animal, and the cost of treatment. The latter category should include the cost of any drugs or other materials used and the labor in their application.
Clinical and laboratory investigations on chronic bovine fluorosis
Authors: Metwalli A. A. , El-Gharieb S. W. , Ashry K. M.
Published: March 2023

During summer 1995, a clinical picture of chronic bovine fluorosis was observed in Fowa villages (Kafr El-Sheikh Governorate) where many brick kilns were established. A total number of 26 cows (5-9 years) of native breed was investigated in the present study. Sixteen animals were collected from different places around the kilns, another 10 animals (control group) were chosen from places away from the brick kilns zone. The affected cows showed reduced appetite, loss in general body condition, lameness and dental lesions in the form of staining, mottling and blackish discoloration specially of the incisors teeth. Biochemical analysis of serum of affected cows revealed significantly decreased level of serum calcium and total protein, whereas serum alkaline phosphatase activity, fluoride content, urea, and creatinine were significantly increased as compared with control animals. Haematological examination of affected cows showed significantly decreased values of Hb and PCV. On the basis of laboratory and circumstantial evidence, the problem was suspected to be fluorosis, possibly due to environmental pollution with fluorine-bearing smoke arising from the large number of brick kilns.
Evaluation of attitudes of participating groups in the Colorado Beef National Animal Health Monitoring System pilot program
Authors: Grotelueschen D. M. , Mortimer R. G. , Salman M. D. , King M. E. , Odde K. G.
Published: March 2023

The National Animal Health Monitoring System (NAHMS) was established due to the need for information concerning the incidence of animal disease and the associated costs of disease. Three basic components were proposed in the pilot phase of NAHMS. They were the epidemiologic component, the economic component, and the evaluation component. The epidemiologic component was concerned with collection of data about disease incidence, including information related to identification of risk factors for disease. The economic component attached monetary significance to health occurrences. It also associated cost/benefit ratios with various management decisions and characteristics of individual operations. Food animal veterinary practitioners increasingly deal with animals on a population basis and can use this information in their animal health programming efforts. The third major component of the NAHMS pilot program in Colorado was the evaluation. Evaluation of the pilot project was essential to improve the program, to provide public accountability, to increase knowledge about it, and to provide assessment criteria for future development. There were two primary areas of focus in the evaluation process. They were the methodology of the study, which included the data collection methods and the procedures used to validate and analyze the data, and NAHMS itself, including input from participants.
Role of the bovine practitioner in cattle welfare
Authors: Webster A. J. F.
Published: March 2023

If the bovine practitioner is to make a positive contribution to cattle welfare then he/she must have a clear understanding of what constitutes welfare as perceived by the cow, and where the main problems are likely to arise. Welfare can be defined by the ability of an animal to sustain fitness and avoid suffering. The high-yielding dairy cow is genetically fit at the onset of her first lactation but then faces physiological demands that are abnormal not in intensity, but in duration. Too many dairy cows culled after only 1-4 lactations are chronically lame or emaciated and appear to be "worn out" by sustained hard work. The main welfare problems for dairy cows in northern Europe can be attributed to systems of feeding, housing, milking and management that are unfitting to the genotype of the high yielding cow. New technologies for the control of breeding or the hormonal manipulation of lactation should be controlled by legislation that gives better protection not just to the veterinary profession but also to the animals. Cattle used for commerce should receive equal protection in the law to that given to animals used for scientific purposes. In each case any cost to the animal must be justified in terms of any potential benefit to society.
Cattle welfare, science and policy
Authors: Wierenga Herman K. , Blokhuis Harry J.
Published: March 2023

This paper summarizes welfare problems in cattle. Behavioural as well as health problems are discussed for veal, beef and milk production systems. In particular in veal calves there are major welfare problems related to small space allowance, individual housing and denial of roughage. In the intensive beef production system there are welfare problems as well (some behavioural problems and leg disorders). Welfare problems in dairy cows are mainly caused by health problems such as claw disorders and mastitis. Welfare problems related to the transport of cattle are briefly described. Finally, potential threats are presented. In selecting programmes for increased meat or milk production, and in further developments of the milking robot and of biotechnology, the possible negative consequences for animal welfare (behaviour and health) need to be taken into account.
Experiences with two BHV1 marker vaccines
Authors: Straub O. C.
Published: March 2023

Both marker vaccines tested were deleted vaccines, one had a gG, the other a gE deletion. The gG deleted vaccine was inactivated the gE deleted vaccine had a live and an inactivated form. The object of the trial was to evaluate these vaccines in heifers and calves. Twenty young heifers were used for the inactivated deleted vaccines and 16 four week old female calves for the gE deleted live vaccine. Animals were three times vaccinated, first at 4 and 7 week intervals and again six or ten months later. Challenge was conducted by placing seronegative fields virus inoculated animals between the vaccines. Neither vaccine was able to prevent infection with filed virus, long virus shedding periods and the establishing of latency. Local reactions were insignificant concerning general health. The humoral response was better after the seven week interval but the protection form clinical disease was not. The live vaccine led to a better protection from clinical disease than the inactivated vaccines.
Management of the high yielding dairy cow
Authors: Albright Jack L.
Published: March 2023

This paper briefly discusses the management of dairy cattle, with particular reference to the following: feeding, and competition within the herd for feed and water resources, stress and how to recognise stressed behaviour in cows, and design of facilities (including milking parlours) to reduce stress and contribute to increasing milk yield.
Physiology and practice of induction and control of oestrus in cattle
Authors: Roche J. F. , Mihm M. , Diskin M. G.
Published: March 2023

This paper reviews current knowledge about the dynamics of ovarian follicle waves in cattle and the hormones associated with them, and gives an account of the rationale for existing and new treatments to control these waves and to synchronize oestrus in order to improve reproductive performance.
Relationship between nutrition and management to lameness in dairy cattle
Authors: Olson Jerry D.
Published: March 2023

Lameness, specifically laminitis, is discussed within the context of rumen acidosis, and heat stress and rumen acidosis.
Serum antibody response in calves receiving modified live and/or inactivated vaccines containing bovine herpesvirus-1, bovine viral diarrhea virus, parainfluenza-3 virus, and bovine respiratory syncytial virus immunogens
Authors: Fulton Robert W. , Burge Lurinda J. , D'Offay J. M. , Payton Mark E.
Published: March 2023

Serum antibody responses to bovine herpesvirus-1 (BHV-1) bovine viral diarrhea virus (BVDV), parainfluenza-3 virus (PI-3V), and bovine respiratory syncytial virus (BRSV) by calves receiving viral vaccines were evaluated. Calves were vaccinated at day 0 with one of four commercial vaccines containing BHV-1, BVDV, PI-3V, and BRSV immunogens. Selected vaccines were given a second time at day 28. Calves were revaccinated at day 140 with the respective vaccine given at day 0. The vaccines contained modified live virus (MLV) and/ or inactivated components. Serums were collected at day 0 and at various intervals through day 196, and assayed for viral neutralizing antibodies. Between various vaccine groups there were differences in onset and duration of serum antibodies to each immunogen postvaccination. Anamnestic responses after day 140 revaccination to some but not all viruses were sometimes dependent on the type vaccine and level of antibodies at revaccination.
Evaluation of viral shedding and immune response following vaccination with a modified live BHV1 vaccine
Authors: Roth James A. , Vaughn Michael B.
Published: March 2023

The purpose of the study was to monitor Bovine Herpesvirus-1 (BHV1) shedding to susceptible herdmates after vaccination with a modified live BHV1 vaccine and to monitor the development of the cell-mediated immune response to BHV1 (as measured by antigen specific lymphocyte blastogenesis). Ten calves received a modified live virus (MLV) vaccine containing BHV1, bovine viral diarrhea virus, parainfluenza 3 virus and bovine respiratory syncytial virus. Five calves that were seronegative for BHV1 served as contact controls. Multiple attempts to isolate BHV1 from nasal swabs and buffy coat cells from vaccinates and control animals between days 0 and 21 were all negative. By six days post-vaccination five out of ten vaccinated calves had a detectable post-vaccination lymphocyte blastogenic response to BHV1 antigen. The response continued to increase until at least 28 days after vaccination, at which time all ten calves exhibited a detectable response. None of the contact control animals developed an antibody or lymphocyte blastogenic response to BHV1 antigens. These results indicate that the MLV-BHV1vaccine used in this study induced an early and strong cell-mediated immune response as measured by lymphocyte blastogenic responsiveness to BHV1 antigens and the vaccine virus was not shed to susceptible herdmates.
Tongue ulcer
Authors: Wentzel Jim
Published: March 2023

Dairy veterinarians often have a diagnosis or at least a short differential list from only the clinical signs even before examining the animal. This article will challenge your diagnosis and lengthen your differential list.
Grumpy old vets
Authors: Nordlund Ken
Published: March 2023

The dairy industry of the upper Midwest is being restructured. The perceived long-term value of a 50-cow tie-stall barn with a vertical silo is low. If the owner is fifty-five years old, the plan is to ride the depreciation out to an unsaleable dairy. If the owner is forty years old, the question is whether to expand substantially or get out now. Paralleling the uncertainty of dairy operators is the palpable uncertainty of upper Midwestern dairy practitioners. The daily activities of a typical Midwestern dairy practice are changed very little from thepractice style that developed thirty years ago. However, that mix of sick cow exams, scheduled reproductive exams, the displaced abomasum surgery, and emergency services are not well accepted in the expanded dairy herds of several hundred cows. The 1960's dairy practice has arrived on the 21st-century dairy farm and whilethe cows look familiar, everything else has changed! This paper will explore some issues, problems, and possible solutions for adapting veterinary services for dairies in the next decade.
Outbreak of encephalitic listeriosis in Holstein bulls
Authors: Ayars William H. , Monke Donald R. , Love Brenda
Published: March 2023

Five Holstein bulls in a herd of 478 bulls were diagnosed with clinical encephalitic listeriosis. Four bulls survived after intensive therapy with oxytetracycline, dexamethasone, and oral fluid with electrolytes. The bull which did not survive had histological findings of lymphoplasmacytic encephalitis and inflammation of the trigeminal ganglion, which were consistent with the diagnosis of clinical listeriosis. A suspect silage sample was submitted for laboratory evaluation. The silage had a pH of 6.9 and was positive for Listeria monocytogenes. In vitro antibiotic testing of the organism isolated revealed resistance to penicillin, the drug commonly recommended for the treatment of listeriosis. It is concluded that caution should be exercised, however, when evaluating in vitro susceptibility results associated with a listeriosis outbreak because multiple ribotypes may be involved.
Uniform protocol for evaluating response to treatment of papillomatous digital dermatitis lesions
Authors: Britt Jenks S. , Berry Steven L. , Shearer Jan , Hemling Tom , Steevens Barry , Dreher Monika
Published: March 2023

Digital dermatitis or papillomatous digital dermatitis (PDD), commonly known as footwarts or hairy heel warts, was first reported in Italy in 197 4 and in New York in the late 1970's. Similar lesions have occurred in 40 or more states in the United States and many other countries. The etiology of this disease is unknown, however, two to five phylotypes of spirochetes (Treponema sp.) have been associated with active lesions and identified by using Polymerase Chain Reaction (PCR), histologic, or microbiological methods.

The purpose of this paper is to develop a uniform protocol which can be used to evaluate results of treatment to control PDD lesions. The remainder of this paper lists our suggestions for information which should be included in each trial protocol.
Testing and Management Strategies for Effective Beef and Dairy Herd BVDV Biosecurity Programs
Authors: Kelling Clayton L. , Grotelueschen Dale M. , Smith David R. , Brodersen Bruce W.
Published: March 2023

Elements of a bovine viral diarrhea virus (BVDV) biosecurity program, associated costs and benefits, and criteria veterinarians and producers can use in considering whether to adopt a program are described in this report. Protection against BVDV infections includes proper immunization, identification and elimination of persistently infected (PI) carrier cattle, and prevention of exposure of cattle at risk to BVDV. The decision to implement a BVDV biosecurity program must be based on a herd-by-herd cost-benefit analysis. Costs include diagnostic testing as well as costs imposed by constraints on production practices, which are necessary to implement the program. Benefits include reduced disease loss, potential added value of replacement breeding animals which can be marketed as test-negative for PI infection, and pregnant females at low risk of carrying a PI fetus. Various herd-level diagnostic strategies have been devised to screen herds for the presence ofBVDV, identify and eliminate PI carrier cattle, or help prevent new exposure of the herd to BVDV. No universally applicable protocol exists for herd level BVDV biosecurity. The specific biosecurity methods used in each herd depend on the type of livestock production system involved. Important variables to consider are the number of animals in the herd, livestock concentration, distribution of animal groups, and desired level of biosecurity assurance. When BVDV virus is known to exist in a herd, control of new infections must take into account the possible presence of PI animals. A single PI animal can serve as the source of virus for a herd, and a stringent herd testing program may be required to identify and eliminate PI animals. Producers must understand the risks of re-exposure occurring in a BVDV-free herd and the importance of continuous management to prevent contact with cattle from other herds. In BVDV-free herds, it is essential to annually test and confirm the BVDV PI-free status of all calves born. Purchased animals should be isolated and tested before being added to the herd to avoid introduction of transiently infected animals. It is strongly recommended that bred heifers from outside sources not be added to the BVDV-free herd. Purchasing tested, non-pregnant replacement heifers is less risky than buying tested pregnant females. If tested, pregnant cattle are purchased, then the offspring must also be tested to confirm their BVDV PI-free status before introduction into the herd.
Teat Dilators as Free Foreign Bodies in the Bovine Teat
Authors: Querengässer Klaus , Geishauser Thomas , Querengässer Julia , Bruckmaier Rupert , Fehlings Klaus , Wolf Winfried
Published: March 2023

The objective of this study is to report two cases of foreign bodies in teats of cows with milk flow disorders. Foreign bodies and the causes of the milk flow disorders were diagnosed and treated by using teat endoscopy. In the first case, a teat dilator was found in the teat along with inflammation of the teat cistern lining. The milk flow disorder was caused by teat canal skin which had ruptured and inverted into the teat cistern. In the second case, a wax teat insert was found in the teat cistern. The milk flow disorder was caused by a narrowed inner opening of the teat canal. In both cases the milk from the affected quarters showed signs of subclinical mastitis. The foreign bodies were removed through the teat canal by using forceps. The causes of the milk flow disorders were treated surgically. Antibiotics were administered into the affected teats and a sterile silicone implant was inserted into the teat canal. The teat was bandaged and rested for several days. On re-examination four weeks later, milk flow and milk quality were significantly improved. Our findings indicate that the alterations in the teat canal area were the cause of the milk flow disorders rather than the foreign bodies. We conclude that in teats with milk flow disorders, a diagnosis should be made first and then a causal treatment initiated. Teat dilators and wax inserts without heads may slip into the teat and act as foreign bodies. Teat dilators may be deleterious to udder health.
Hail Bruising of Fed Cattle
Authors: Schmidt Ty B. , Unruh Luke , Perino Louis J. , Montgomery Ted H.
Published: March 2023

On May 25, 1999, a storm producing hail approximately 1 ¾ to 3¾ inches in diameter crossed over a feed yard. On four occasions following the storm, 409 carcasses from six pens were observed at an abattoir. On day 1, 29 carcasses were examined at the abattoir and in the grading cooler. On days 10, 15, and 49, additional cattle (n = 117, 173, and 90, respectively) were examined at the abattoir only. On day 16 following the first storm, a second storm, producing approximately 1 ¾-inch-diameter hail, crossed over the feed yard. Bruises were classified into three size categories, into short- and long-duration categories, and location was recorded. One hundred, 85, 54, and 44% of the carcasses exhibited bruises on days 1, 10, 15, and 49, respectively. On days 1, 10, 15, and 49, 100, 98, 65, and 27% of bruises were classified as short-duration. Multiple bruises were observed on 100, 75, 42, and 16% of carcasses on days 1, 10, 15, and 49, respectively. Storms producing hail approximately 3¾ inches in diameter have the potential to cause extensive bruising in cattle in open feed yards. Cattle sold within 15 days of such storms may experience significant hail-associated carcass trim loss, but by day 49 bruising appears to return to baseline levels.
Case report
Authors: Hammer Elizabeth J. , Hawkins Jan F. , Divers Thomas J. , Sammons Lynn
Published: March 2023

A two week-old Holstein heifer was examined for dribbling of urine and scalding of the perineum since birth. The history and clinical findings were suggestive of an ectopic ureter. Contrast radiography, endoscopic examination of the vagina and urinary bladder, and ultrasonography were supportive of a left ectopic ureter. A definitive diagnosis of a left ectopic ureter and hydronephrosis was made during abdominal exploratory surgery. The left kidney and ureter were removed. The calf recovered without complications or urinary incontinence.
Herd Level Information and Bulk Tank Milk Analysis
Authors: Jayarao Bhushan M. , Pillai Shreekumar R. , Wolfgang David R. , Griswold David R. , Hutchinson Lawerencee J.
Published: March 2023

When milk produced on a farm is examined for bacteriological milk quality and mastitis causing bacteria, it can disclose descriptive information about the general udder health status of the herd, milk hygiene and milking practices on the farm. Many dairy producers periodically receive information about their bulk tank milk with reference to standard plate counts and bulk tank somatic cell counts. Some dairy producers also receive a report on preliminary incubation counts. This information, when collected over a period of time, in combination with bulk tank mastitis culture reports can become a significant knowledge base. This comprehensive data, when interpreted in context with the farm's management practices, provides a rationale to determine current and potential milk quality and mastitis problems in a herd. This paper describes the process of collecting, analyzing, and interpreting bulk tank milk microbiology test results, and utilizing the information to make decisions on improving udder health of the herd and improving milk quality.
Evaluation of three methods to clean feedlot water tanks
Authors: Smith David R. , Klopfenstein Terry , Moxley Rodney , Milton C. Todd , Hungerford Laura , Gray Jeffrey T.
Published: March 2023

Three methods of physically or chemically cleaning cattle feedlot water tanks were tested for their ability to reduce amounts of coliform bacteria in the water and the surface of the tank (biofilm) during the summer months: in the first method, the water tank was drained and refilled; in the second method, the water tank was scrubbed with a bootbrush to loosen and remove any visible sediment, drained and refilled; and in the third method, water tank was scrubbed with a brush (as above), drained and refilled. Household chlorine bleach (5.25% Na hypochlorite) was added to the water tank to a final 1:32 dilution. The disinfectant solution was kept in the tank for 15 minutes before the tank was drained again and refilled. In Trial 1, we found that the first and second methods did not reduce coliform bacteria in water or biofilm. On the other hand, coliform bacteria in water and biofilm were reduced 99% (p=0.0003) and 99.9% (p<0.0001), respectively, after draining, scrubbing and 15 minutes of chemical disinfection with chlorine bleach and refilling (method 3). However, coliforms returned to pretreatment levels 24 hours after treatment (p=0.12). In Trial 2, we demonstrated that the rapid re-population in coliform bacteria was due to the cattle drinking from the tanks (p=0.0003). These data indicate that coliform bacteria rapidly re-populate water tanks in the summer because cattle re-contaminate them with coliform bacteria and/or substrate. If the overall number of coliforms in a water tank reflects the likelihood of transmitting coliform bacteria from water tanks to cattle, then the benefits of cleaning and disinfecting water tanks to minimize the transmission of coliform bacteria to cattle are short-lived.
Case report
Authors: Prado Tulio M. , Morgan Gregor L. , Prado Maria E. , Bahr Robert J. , Streeter Robert N. , Emmett Gregory
Published: March 2023

A 4-year-old female llama was admitted to the veterinary teaching hospital with a 12-month history of urinary incontinence and scalding of the perineum and rear limbs. Before the development of the presenting complaint the llama experienced a complicated dystocia. A diagnosis of urine pooling was made following an initial physical exam. Surgical correction was attempted using a urethral extension technique previously described in the cow. However, the llama continued to pool urine post-surgery. After further vaginal examination using endoscopy, a urethrovaginal fistula was diagnosed 10 cm caudal to the cervix, midway between the cervix and the cranial portion of the extended urethra. A second surgery was undertaken to close the fistula. The llama recovered uneventfully, urine pooling ceased and the scalded areas healed. Urethrovaginal fistulas have not been previously documented in llamas.
Economic evaluation of beef cowherd screening for cattle persistently-infected with bovine viral diarrhea virus
Authors: Larson R. L. , Pierce V. L. , Grotelueschen D. M. , Wittum T. E.
Published: March 2023

Bovine viral diarrhoea virus (BVDV) infection is responsible for a variety of economically important syndromes in cattle. In order to quantify the economic benefit for removing BVDV persistently infected (PI) animals, a 10-year farm profitability simulation model was used to compare production scenarios with and without PI calves present. Differences in profitability between the scenarios, estimates the value of diagnostic testing given the expected prevalence in the herd. If the true prevalence of herds with at least one PI animal is 1% (low end of the 95% confidence interval for randomly selected herds), the average annual dollars available for screening is only $0.15. Using a 10-year period, if the whole herd is tested the initial year and the cost of the initial screening is pro-rated over 10 years, and only replacements are screened in subsequent years, $0.60 is available for costs associated with each animal tested. If, however, the true prevalence of herds with at least one PI animal is 30% (high end of the 95% confidence interval for pre-screened herds), the average annual dollars available for screening is $4.60. In this scenario, $18.40 is available for each animal tested. These figures show that practitioners may not be economically justified to initiate diagnostic screening protocols for PI BVDV cattle for all clients. However, if ranch history raises a suspicion of BVDV PI cattle being present, a screening protocol can be defended based on its likelihood to improve economic return.
Bovine coccidiosis
Authors: Step D. L. , Streeter R. N. , Kirkpatrick J. G.
Published: March 2023

Coccidians are protozoal parasites that are host specific, transmitted by the fecal-oral route and cause enteritis. Economically significant species discussed in this paper that cause disease in cattle belong to the genus Eimeria. Young animals are more susceptible to clinical disease than older cattle. Coccidiosis is frequently observed in stressed, overcrowded and confined conditions, however, the disease can occur on pasture. The disease can occur any time of the year but is more prevalent during winter months, even in confinement operations. Animals may pass oocysts in their feces without clinical disease, therefore, a diagnosis of coccidiosis is based on clinical signs and ruling out other diseases. Identification of coccidian postmortem specimens supports the diagnosis. Management procedures that reduce stress and prevent contamination of feed and water are important in preventing coccidiosis. Effective control programs also commonly incorporate the use of medicated feed or water. Drugs commonly used in the US for coccidiosis control and prevention programs include monensin, lasalocid, decoquinate and amprolium. When clinical disease is present, amprolium, sulfonamides and management changes are used to control the disease.
NYSCHAP Johne’s Disease Module, A Program to Change Management of Dairy Farms to Reduce Johne’s Disease Prevalence
Authors: Wapenaar W. , Van Schaik G. , Leids P. , Denney L. , Schukken Y. H. , Stehman S. M. , Huntley J.
Published: March 2023

characteristics of farms (herd size, objectives to join, etc.) which participated in the core and Johne’s disease (JD) modules of the New York State Cattle Health Assurance Program (NYSCHAP). In addition, we evaluated whether the NYSCHAP JD module was successful in motivating farmers to adopt recommended management practices that limit transmission of enteric diseases, including JD. First, descriptive parameters of farms engaged in the NYSCHAP were determined. Second, adoption of recommended management practices was evaluated in a sub-group of farms.The average NYSCHAP herd was larger than the average dairy herd in New York state and had higher milk production. Goals for participation in the JD module mentioned most frequently by participants were 1) limit transmission of the disease, 2) become a JD negative herd and 3) gain information and have knowledge to change management on the farm. Most farms (94%) intended to do some kind of herd testing for JD and 83% intended to test 75-100% of their herd. The large number of laboratory tests conducted for each farm showed that completed testing corresponded with intended plans. The average percentage of advised management practices implemented by a sub-group of NYSCHAP herds was 74%. This indicates that the average farm appeared to implement 13 of 17 advised measures. An educational, process-oriented program, such as NYSCHAP, may be a successful way to encourage producers to improve herd health management on farms.
Are Our Feeding Programs Contributing to Environmental Contamination?
Authors: Meyer Deanne
Published: March 2023

New Federal regulations related to concentrated animal feeding operations will prompt many states to increase permitting of these facilities. Included in the permit process with be greater accountability of land application of manure nutrients. In areas where livestock producers do not have sufficient land available for crop production to utilize manure nutrients, alternative utilization methods will need to be identified. The first logical step is to evaluate the dietary nutrient concentrations and make source reductions by reducing these inputs. It is critical that least cost ration formulation include the cost of manure nutrient utilization. Practitioners can assist their clients: identify reliable sources of information, understand new regulations and associated critical control points, assist clients with compliance assistance programs, encourage clients to keep records, identify consultants with expertise in crop production, assist clients in checking references of potential consultants, and encourage clients to make direct contact with regulatory agency staff.
Diagnostic complications from "fecal" trichomonads
Authors: Bagley Clell V. , Paskett Michael E.
Published: March 2023

Routine methods for the culture of Tritrichomonas foetus cannot differentiate between it and faecal/enteric trichomonads. Faecal/enteric trichomonads can contaminate the sheath of bulls and result in their being classed as infected with trichomonads. Current Utah regulations require the slaughter of all trichomonad-positive bulls. The presence of faecal/enteric trichomonads is documented, but the extent in Utah is unknown. Culture of faecal samples from 55 bull calves in 11 herds was conducted to recover trichomonads. The faecal samples were collected on 29 October 2002. Typical positive trichomonad cultures were found in 23 of 55 faecal samples (42%), and in all of the 11 herds (100%). Three samples with the heaviest growth of trichomonads were sent to a second laboratory for PCR and staining diagnostics. All 3 isolates were negative using T. foetus-specific PCR primers. They were also observed to have 4 anterior flagella and were classified as Tetratrichomonas species. These results indicate that faecal trichomonads are common in cattle of Utah and southern Idaho. There is no evidence that this type of trichomonad is pathogenic. Regulations need to allow for further specific identification of trichomonad organisms from young bulls, and especially for valuable bulls.
Comparative efficacy of a novel intramammary dry cow antibiotic to eliminate subclinical mastitis in the dry period
Authors: Dingwell R. T. , Duffield T. F. , Leslie K. E. , Keefe G. P. , DesCoteaux L. , Dick P. , Bagg R.
Published: March 2023

Although there is increasing concern over routine administration of long-acting antibiotics to all cows at the end of lactation, the practice is required to eliminate subclinical infections that are present at drying off. Alternatives to dry cow therapy (DCT) for preventing new infections from occurring in uninfected quarters in the dry period are increasingly common. However, until a cost-effective and reliable test becomes available to determine which cows and quarters are not infected at drying off, administering DCT to all quarters and all cows remains the recommended practice. The efficacy of a novel intramammary treatment containing tilmicosin, administered at drying off to eliminate mastitis pathogens other than Staphylococcus aureus, was compared to intramammary cloxacillin. Data from 406 infected quarters, representing 238 cows that either received intramammary tilmicosin or benzathine cloxacillin, were analysed. The study was conducted in Ontario, Quebec, and Prince Edward Island in Canada for a period of one year, beginning in July 1999. Results showed that 11% of quarters had a major mastitis pathogen recovered prior to the dry period. The overall cure rate of mastitis pathogens following administration of DCT was 89.2%. The cure achieved with intramammary tilmicosin was 87.2%, whereas for cloxacillin it was 90.9%. There was no significant difference in the cure rate between the 2 treatments, either in overall cure, or cure of any specific pathogen. Results of the final logistic regression models to determine factors associated with the probability of infected quarters to cure during the dry period reemphasized the importance of dry period length, season of drying off, and general environmental exposure. It is concluded that intramammary tilmicosin is as efficacious as benzathine cloxacillin for eliminating existing infections caused by pathogens other than S. aureus during the dry period. No commercial preparation of intramammary tilmicosin is currently available.
Tail docking and animal welfare
Authors: Ruegg Pamela L.
Published: March 2023

Tail docking is a common practice on many dairy farms, and is perceived by many farmers to improve cleanliness and enhance milking parlour efficiency. It is a controversial practice attracting increasing scrutiny by the animal welfare community. Scientific studies have been performed to evaluate physiological and behavioural responses to tail docking in preweaned calves and preparturient heifers. The effect of tail docking on animal behaviour, indicators of pain, fly avoidance behaviours, immune responses and circulating plasma cortisol have been reported. Additional studies have been performed to evaluate the effect of tail docking on cleanliness and udder health in lactating dairy cows. The purpose of this paper is to review current research related to tail docking in dairy cattle.
Record keeping system for capture of lameness and foot-care information in cattle
Authors: Shearer Jan , Anderson David , Ayars William , Belknap Ellen , Berry Steven , Guard Charles , Hoblet Kent , Hovingh Ernest , Kirksey Glenn , Langill Alan , Mills Arlen , Miskimins Dale , Osterstock Jason , Price Richard , Prigel David , Roussel Allen , Van Amstel Sarah , Wallace Richard , Wasson James , Cook Nigel , Garrett Edgar F. , Hostetler Douglas E. , Schugel Lavern
Published: March 2023

The American Association of Bovine Practitioners' (AABP) Bovine Lameness Committee met for the first time at the association's annual convention in Rapid City, South Dakota, in September 2000. The committee developed a mission statement and established a series of subcommittees to address specific issues. One subcommittee accepted the challenge to develop a system for recording lameness, trimming and foot care information. Objectives were to devise a system that would be simple to use, compatible with Dairy Herd Improvement Association record keeping systems or other record keeping programmes, and in agreement with internationally recognized definitions and nomenclature used to describe lameness conditions. With this system the veterinarian, trimmer or data recorder is required to identify specific lameness conditions through the use of a single upper case letter, which serves as the specific code for a particular disorder. In most cases, this letter corresponds to the first letter of the name for the lameness condition in question. If desired, lower case letters may be used as sub-codes to provide more detailed descriptions. Upper case letter codes are combined with numbered claw zones that specify location of the lesion. Whereas nine claw/foot zones were identified in the original diagrams, this system permits identification of lesions in four additional areas, including the interdigital skin, palmar/plantar interdigital cleft and axial wall. Using this system, lameness conditions may be simply and accurately documented by use of the upper case letter and number corresponding to the appropriate zone or region of the claw or foot affected. Claws, feet and limbs are identified or numbered from left to right beginning with the left front foot; left front lateral claw (LFL) #1, left front medial (LFM) claw #2, right front medial (RFM) claw #3, right front lateral (RFL) claw #4, left rear lateral (LRL) claw #5, left rear medial (LRM) claw #6, right rear medial (RRM) claw #7, and right rear lateral (RRL) claw #8. A foot or limb may be designated by use of the appropriate capital letters or both claw numbers; left front (LF) foot or limb #12, right front (RF) foot or limb #34, left rear (LR) foot or limb #56, and right rear (RR) foot or limb #78. This system provides a flexible yet uniform model for the capture of lameness information that will assist veterinarians, trimmers and others in the evaluation and monitoring of lameness and foot care information in cattle.
AABP Association and Conference News
Authors: American Association of Bovine Practitioners
Published: March 2023

Highlights of the Annual Conference of the American Association of Bovine Practitioners (37th : 2004), officers, district news, events, awards, and other news.
Update on dairy cow free stall design
Authors: Cook Nigel B. , Nordlund Ken
Published: March 2023

This paper summarizes recent advances in our knowledge of free stall design for dairy cows. New information related to free stall surface cushion and traction, resting space, head lunge and bob movement and neck rail location is reviewed and summarized. Diagonal lying of cows in stalls has several potential adverse effects, and can result from mechanical and social obstructions related to overall stall size. Recent research has shown that lame cows behave differently on mattress than on sand surfaces. It is likely that lameness is a risk factor for other stall injuries and entrapments. Currently, sand remains an optimal stall surface for the dairy cow as its cushion and traction allows lame cows to maintain normal patterns of daily stall activity.
Respiratory tract infections in dairy calves from birth to breeding age
Authors: Step D. L. , Confer A. W. , Kirkpatrick J. G. , Richards J. B. , Fulton R. W. , Payton M. E.
Published: March 2023

This observational study followed 30 dairy heifers from birth to breeding to identify when exposure to potential respiratory pathogens occurred. Following the standard heifer development protocol for the dairy farm studied, heifers were housed in larger group pens, termed "groupings", based upon individual growth and development. Samples were collected at each grouping to determine when potential respiratory pathogens were acquired. Nasal swabs for viral and bacterial culture, peripheral blood leukocytes for virus isolation, and sera for antibody titers were collected and assayed three times (days 0, 7 and 14) at each grouping, beginning at 24-36 hours of age. Nasal bacterial isolates included Mannheimia haemolytica, Pasteurella multocida, Histophilus somni (formerly Haemophilus somnus) and Mycoplasma spp. M. haemolytica and P. multocida were occasionally isolated in the first 24-36 hours of life. Isolation of M. haemolytica and P. multocida increased substantially in the second and fourth groupings, respectively. Bovine herpesvirus-1 (BHV-1), parainfluenza-3 virus (PI3 V), M. haemolytica and Mycoplasma spp. were isolated with increased frequency when heifers were housed with nose-to-nose contact with adult cattle, and when clinical respiratory disease that responded to treatment occurred. Heifers were vaccinated with modified live virus vaccine while in hutches and at 5-6 months of age (third and fourth groupings). Colostrum-derived antibodies to viruses had diminished by the second grouping (age 95.2ñ25.4 days), and during that time PI3 V and BHV-1 were isolated. Viral neutralizing antibody titers did not significantly increase until after the second vaccination, which may have reflected interference from maternal antibody. Calves spontaneously developed antibodies to P. multocida between the 14th day in the hutch and the second grouping, and to M. haemolytica during the second (age 95.2ñ25.4 days) and third groupings (age 134.5ñ36.1 days). In conclusion, transmission of potential respiratory pathogens was documented in young dairy heifers despite commonly accepted health management programs, including vaccination.
Atrial septal defect
Authors: Kaiser Lana , Ames N. Kent , Patterson Jon , Bell Thomas G.
Published: March 2023

This study was designed to determine the time sequence of postnatal changes associated with the atrial septum in the bovine heart, and to assess if atrial septal defect (ASD) is a genetic disorder in stillborn Maine-Anjou calves. The study was divided into three parts: (1) review of the necropsy database; (2) examination of hearts from "normal" Holstein-Friesian calves; and (3) examination of hearts from stillborn beef calves and cattle dying of unknown cause. In the normal Holstein-Friesian calf the opening in the atrial septum is covered completely by a membrane at birth, resulting in an anatomic but not a physiologic opening, and closes completely between seven and 14 days of age. The same time sequence appears true for hearts from beef calves. Of the 27 hearts from beef cattle examined, six bull calves (three purebred Maine-Anjou, two Maine cross, one Shorthorn) and one 18-month-old Maine cross heifer had an ASD, which included both an opening in the atrial septum and an abnormal membrane. ASD is likely a genetic disorder of cattle, which may have a greater gene frequency in the Maine-Anjou breed.
Baseline management practices and animal health data reported by US feedlots responding to a survey regarding acute interstitial pneumonia
Authors: Woolums Amelia R. , Loneragan Guy H. , Hawkins Larry L. , Williams Shamita M.
Published: March 2023

Little is published regarding management practices at US feedlots. As part of a study to characterize management practices related to feedlot acute interstitial pneumonia (AIP), baseline health and management data were collected by a cross-sectional survey sent to 561 feedlots in 21 states. Of 72 surveys (12.8%) returned, 53% came from Kansas and Nebraska. The total number of cattle placed by respondents was 2,495,439, representing approximately 10% of cattle placed in feedlots in 2000. Respondents placed 1,385,644 steers, 1,011,905 heifers, 48,987 Holsteins and 48,903 other cattle. Viral respiratory vaccination was common, while fewer feedlots vaccinated against bacterial respiratory pathogens. Sixty-one percent of respondents practiced mass antimicrobial administration to cattle, although only 17% of all cattle were mass-treated. Hormonal implants were used by 92% of feedlots, and approximately 80% of them used a final implant containing trenbolone acetate (TBA). Heifers were implanted with products containing higher doses of TBA than steers. Monensin and melengestrol acetate were included in the summer finishing diet by 97% and 75% of the respondents, respectively. Sixty-five percent of animals that died received a postmortem examination. Bovine respiratory disease complex (BRD) was the leading cause of morbidity and mortality: 12.8% of placements were treated for BRD, and 0.8% died of BRD. Of all placements, 1.3, 1.6 and 2.6% of cattle were treated for AIP, digestive disorders and all other diseases, respectively; 0.1, 0.3 and 0.2% of placements died of AIP, digestive disorders and all other diseases, respectively.
Probable source of Neospora caninum infection in an abortion outbreak in dairy cows
Authors: McAllister Milton M. , Wallace Richard L. , Bjorkman Camilla , Gao Liying , Firkins Lawrence D.
Published: March 2023

A small dairy had an outbreak of neosporosis. One-third of pregnant cows aborted or gave birth to a weak, premature calf over a period of 11 weeks. Serologic results of a Neospora caninum avidity enzyme-linked immunosorbent assay (ELISA) test were indicative of widespread, recently acquired infections in the cows and also in the farm dog. This dog was accustomed to sleeping and defecating in a pile of chopped hay used in the total mixed dairy ration, so it was a possible vector of infection in this outbreak. Replacement heifers, which did not consume the mixed ration or the chopped hay, had a low seroprevalence to N. caninum and did not have abortions. A new isolate of N. caninum, designated NC-Illinois, was obtained from a premature calf. The circumstances at this dairy illustrate a specific management factor that could help prevent outbreaks of neosporosis. To reduce the risk of infecting cattle with N. caninum, dogs and coyotes, which are definitive hosts of this parasite, should be prevented from defecating in stored feedstuffs. The small dairy in this study might have prevented the outbreak by simply keeping the door to the hay room closed. Large dairies could prevent contamination of stored feedstuffs by erecting a chain-link fence with automatic gates around the area where piles of silage and commodities are kept.
Review of milking machine-induced teat-end lesions and susceptibility to mastitis
Authors: Alekish Myassar O. , Kenyon Simon J.
Published: March 2023

Milking machine-induced teat lesions are commonly thought to be related to increased susceptibility to new intramammary infections. Many of the mechanisms of dimensional and physiological changes in the teat during milking, such as congestion and oedema, are quite well understood. Loss of keratin from the teat canal during milking is believed to lead to increased susceptibility to penetration and colonization by bacteria, but this effect is counterbalanced by the apparent protective effect of the proliferative response to mechanical stress on the teat. This leads to increased regeneration of keratin in the teat canal and hyperkeratosis of the teat-end. Severe teat-end lesions clearly increase susceptibility to new intramammary infections, while some degree of mild hyperkeratosis exerts a protective effect. There is conflicting evidence as to whether moderate hyperkeratosis of the teat-end affects susceptibility to new mastitis infections. Machine-induced teat-end changes may increase susceptibility to mastitis in the presence of other management failures, such as poor milking hygiene.