bluuebunny/crossref_metadata_2025 huggingface dataset:
Prospects For a Preclinical Diagnostic Test
Authors: Sommerville R. A. , Farquhar C. F. , Birkett C. R.
Published: March 2023

At present diagnosis of BSE in cattle and sheep scrapie routinely requires post-mortem confirmation which is traditionally performed by neurohistological examination for Spongiform Vacuolation. Detection of disease specific forms of the host protein PrP, called PrPSc, offers alternatives. Deposits can be detected immunohistochemically, by searching tissue extracts by electron microscopy for the fibrils (scrapie associated fibrils: SAF) which are comprised of PrPSc, or immunoblotting of tissue extracts for PrPSc. In this paper we examine the possibilities of using the immunochemical detection of PrPSc diagnostically. We have raised antibody reagents to PrP, used them to determine the kinetics of PrPSc deposition in murine models of the disease and to determine if PrPSc can be detected in ruminant tissues from BSE or scrapie infected animals.
Can a Link Between Cattle and Human Disease be Proven or Disproven?
Authors: Bruce M. E.
Published: March 2023

There are numerous laboratory strains of transmissible spongiform encephalopathies (TSEs), distinguishable on the basis of their disease characteristics in panels of inbred mouse lines.1 The main criteria used to identify different TSE strains are the incubation periods of the disease in these mice and the distribution of pathological changes seen in their brains, expressed as a "lesion profile". Studies on TSE strain characteristics after passage in hosts of different species or genotypes have shown that the agent contains an informational component that is independent of the host.2,3 In recent years strain typing methods have been used to explore epidemiological links between spongiform encephalopathies occurring in different species.
Vaccination with bovine herpesvirus 1 inactivated vaccine cannot be considered as a stimulus of reactivation
Authors: Thiry Etienne
Published: March 2023

In countries where bovine herpesvirus 1 (BHV-1) infection is highly prevalent, repeated vaccinations of seropositive cattle are recommended to reduce virus circulation with the aim of reaching infectious bovine rhinotracheitis (IBR) free status. In this context, it was of great importance to investigate whether or not vaccination of seropositive latently infected cattle with inactivated vaccine could induce BHV-1 reactivation and re-excretion. Six seronegative calves were intranasally infected with BHV-1 Iowa strain. Four months later, they were randomly allocated in two groups. Four animals were vaccinated twice, four weeks apart, with an adjuvanted inactivated BHV-1 vaccine and two animals were used as controls. After viral inoculation, all calves excreted large amounts of viruses. Following each vaccination, no infectious virus was isolated in the nasal secretions of calves. Three weeks after the second vaccination, all calves were subjected to a five consecutive days dexamethasone treatment to reactivate putative latent virus. Although the magnitude of virus shedding was lower in vaccinated than control calves, all animals re-excreted virus after dexamethasone treatment. This study demonstrates that vaccination of latently infected animals with an inactivated BHV-1 vaccine does not provoke virus re-excretion, and therefore, in our conditions of work, is not considered as a reactivation stimulus.
Age and the effectiveness of chewing during eating in Holstein cows
Authors: Corley R. N. , Murphy M. R. , Wold J. E.
Published: March 2023

Six lactating Holstein cows with rumen cannulae were separated into age groups of 3, 4 and >5 years old, to examine the potential effect of age on the effectiveness of chewing during eating. The first 15 boluses swallowed during a meal of high-quality long lucerne hay were collected from the cardia to determine their mean particle size and weight. The mean particle size of the swallowed boluses did not differ between age groups. As the meal progressed, the mean particle size of boluses decreased from 3.1 to 1.9 æm. The weight of the swallowed boluses was also unaffected by age. There did not appear to be any relationship between the weight of the swallowed bolus and the time it was collected or mean particle size. Over the normal productive lifespan of cows in the USA, age does not appear to greatly affect the effectiveness of chewing.
Thirtienth Annual Conference of the American Association of Bovine Practitioners
Authors: American Association of Bovine Practitioners
Published: March 2023

Description of the 30th American Association of Bovine Practitioners Conference, 1997.
Management of a Salmonella outbreak on a dairy farm
Authors: Larew Alecia L.
Published: March 2023

A 200 cow dairy in Northeast Ohio experienced an outbreak of Salmonella typhimurium during the spring of1994. In addition to human health implications, Salmonella outbreaks negatively impact herd health and productivity. As the United States Department of Agriculture institutes changes in the current inspection system to focus on microbial contamination of food, a greater emphasis will be placed on controlling the disease agent on the farm. This challenges both veterinarians and farmers to work as a team to institute management changes that will result in lowering the number of pathogenic organisms associated with foods of animal origin prior to their entry into the food chain. This paper reviews this Salmonella outbreak, offers management suggestions to control the disease agent, and describes how the problem was resolved on this farm.
Determination of alpha-toxin antibodies against Staphylococcus aureus and phagocytic ability postimmunization in rabbits
Authors: Han Hong Ryul , Park Hee Myung , Kim Doo
Published: March 2023

30 rabbits were inoculated i.m. 3 times, at 2-week intervals, with a S. aureus subunit bacterin preparation (10 HU of alpha-toxin, 600 æg of capsular polysaccharide, 200 æg of fibronectin binding protein). The levels of specific antibodies against alpha toxin in immunized rabbits were significantly increased over 4 weeks compared with control rabbits, which showed no response. There was no significant difference between immunized and control rabbits in bacterial clearance rate. The use of the vaccine for prevention of bovine mastitis is discussed.
Systems electronic information
Authors: Waddell James
Published: March 2023

The Internet is a loosely organized and as yet unregulated network of computers. It stretches across the entire world, knowing no political or geographic boundaries. The physical connections are usually high speed, dedicated telephone lines. They may be old-fashioned copper wires, modern fiber optics, microwave or even satellite lines. There is much redundancy in the connections and the routing of information occurs almostrandomly. A computer in Minneapolis may connect to one in California by way of Denver one day and Washington, D. C. the next. No one person or even organization knows exactly how the Internet works. Local system administrators know how their own part of the network operates and what other remote systems they are connected to.
Alleviated nutrient imbalance by monensin premix (Romensin®, Rumensin®)
Authors: Jonker L. J. , Wilkinson J. I. D. , Tarrant M.
Published: March 2023

In a European series of studies, the effects of administering monensin premix (Romensin®, Rumensin®) to dairy cows via the feed were examined. A total of 365 cows received either 0 or 300 mg monensin per cow per day from approximately one month post calving onwards. Blood samples were examined for ketone levels (beta-hydroxybutyrate and acetoacetate). Cows were categorized for ketonaemia risk by using their average ketone levels for up to five months of treatment. Mean ketone levels of or below 1.0 mmol/1 were considered to indicate normal values. Cows with normal ketone values were categorized into three groups: low normal (≤.50 mmol/1), medium normal (>0.50 to ≤0. 75 mmol/1) and high normal (>0. 75 to ≤1.00 mmol/1). Ketone levels above 1.00 mmol/1 were considered to indicate a ketonaemic condition. Cows treated with monensin were approximately twice as likely to occur in the lowest normal risk category and were approximately half as likely to occur in the highest normal category than control animals. Five percent of the control cows were found in the ketonaemic condition category versus one percent of cows which had received monensin. The difference between the two groups was significant (p<0.001).

These findings were most likely caused by the effects of monensin on rumen fermentation, increasing the production of propionic acid and increasing the supply of glucogenic nutrients derived from the ration. In these studies, monensin apparently alleviated nutrient imbalance and reduced the risk of ketonaemia in dairy cows during early lactation.
Clinical and subclinical events related to the presence of mycotoxins in cattle feed
Authors: Schuh M.
Published: March 2023

An overview is given of the most important mycotoxins affecting cattle and cases which occurred in Austrian dairy herds and steer fattening units are described. Feeding studies with zearalenone- and vomitoxin-contaminated feed and their effect on dairy cows are also reported.
Antibiotic residues
Authors: Neubauer Gary D.
Published: March 2023

Milk residues - just the mention of it creates fits of anger, anxiety, fear, confusion and distrust. There are many perceptions on how and why residues occur but in reality are they truely accurate or are they painstakingly misleading? My hope is that this paper can give you the facts and information to make sound decisions and recommendations for the dairies that you work on.
Control of inflammation in experimental bovine pneumonic pasteurellosis
Authors: Bureau F. , Van de Weerdt M. L. , Hanon E. , Pastoret P-P , Lekeux P.
Published: March 2023

An experimental model of bovine pneumonic pasteurellosis was used to compare the effects on lung mechanical, gas-exchange, biochemical and cellular parameters before and after a nonsteroidal and a steroidal anti-inflammatory drug. Eight Friesian calves were inoculated with Pasteurella haemolytica. After randomisation, 4 calves were treated with a nonsteroidal drug (ketoprofen) and 4 calves with a short-acting dexamethasone solution, all in combination with antibiotics for three days. The calves were inoculated a second time, three days after the last treatment. Flow cytometry was used to differentiate blood mononuclear cells and to measure oxidative burst capacity of anti-inflammatory cells in venous blood and in brochoalveolar lavage samples before and after inoculation and treatment. After the first inoculation, all calves had increased respiratory rates, rectal temperatures, increased neutrophil blood count, and a decline of the arterial pressure in oxygen and lung compliance. After treatment, rectal temperature dropped significantly (P < 0.05) and a higher arterial pressure in oxygen was found in both groups. However, there was only in the ketoprofen group a significant reduction of the tachypnea. After the second inoculation, a significant drop of the arterial pressure in oxygen and a significant higher respiratory rate was seen only for the dexamethasone group, while a significant neutrophilia was found only in the ketoprofen group. No important treatment differences of oxidative burst activity were evident using the flow cytometry technique due to the large within treatment group variability. In this model of lung inflammation, there was a significant higher impairment of the lung mechanics and the arterial pressure in oxygen after the second Pasteurella challenge for the dexamethasone group compared to the ketoprofen treated calves.
Effects of teat dilators, teat cannula and a natural teat insert (NIT) on teat cistern lining during temporary cessation of milking
Authors: Geishauser T. , Seeh C. , Bostedt H.
Published: March 2023

Three lactating cows each were inserted with a teat dilator, a gut string teat dilator, a teat cannula or a natural insert into all teats. All teats of 3 control cows were not treated. Milking was ceased for 5 days and all devices were left in the teats during that period. All teats were examined by endoscopy before and after insertion. By day 6, all teats inserted with a teat dilator, a gut string teat dilator or a teat cannula showed severe proliferative inflammation and injuries of the teat cistern lining. All teats inserted with the natural insert and controls were grossly normal.
Is bovine mastitis being reduced?
Authors: Booth James M.
Published: March 2023

The International Dairy Federation has carried out surveys of its member countries at 5 year intervals in an attempt to quantify the mastitis situation and monitor progress in control. The survey takes the form of a questionnaire which has gradually expanded and now includes questions on the dairy cow population, mastitis control schemes, monitoring procedures, mastitis control measures, milk payment, progress in mastitis control and future plans. Nine countries replied to the first questionnaire in 1973; by 1994 this had increased to 24 countries. Data on mastitis cell counts have been available in some countries from the first survey, but seven countries were still unable to provide national data in 1994. Most of the available data demonstrate a reduction in national average cell counts. In the 1994 survey 13 countries recorded a reduced cell count since 1990 although 21 considered there had been definite or some improvement recently. Few data are available on the national situation on subclinical and clinical mastitis and comparative information is rare. In the same survey the prevalence of subclinical mastitis had been reduced in 3 of 7 countries since 1990 and the incidence of clinical mastitis had been reduced in 2 of 6 countries. These data indicate little progress in reducing mastitis in recent years.
Environmental assessments
Authors: Forbes A. B.
Published: March 2023

Environmental safety is an important consideration in the registration and use of veterinary products in farm livestock. A common approach to environmental risk assessment is through a tiered testing system in which compounds may be taken through a gradation of tests of increasing complexity and scale. Whilst activity at lower tiers is not necessarily predictive of impact in the field, absence of effect in small scale studies generally obviates the necessity to proceed to larger scale testing. If effects are observed in the initial experiments, then the likely environmental impact of a particular compound can be estimated from consideration of the predicted exposure of non-target organisms to the active ingredient and its physico-chemical and biological characteristics. Confirmation that environmental impact assessments based on this type of extrapolation are valid can be determined through further testing of products at higher tiers representative of conditions of particular use. Testing at these higher tiers is logistically more demanding and limits the degree of control and replication compared to that which can be achieved in the laboratory, however the results are more closely allied to normal farm conditions and evaluations can include population and community measurements.
AABP Association and Conference News
Authors: American Association of Bovine Practitioners
Published: March 2023

Description of the Annual Conference of the American Association of Bovine Practitioners (31st : 1998), officers, district news, events, awards, and other news.
Standardized Performance Analysis (SPA)
Authors: Collett Shan
Published: March 2023

Standardized Performance Analysis (SPA) is a systematic approach to tracking beef cattle production (SPA-P) and finances (SPA-F). This paper considers 15 important financial measures, and for each of them illustrative calculations are given and interpretations and limitations of the measure are discussed. The article is intended to provide information that will assist in making profitable production-based decisions.
Risk assessment
Authors: Powell Douglas
Published: March 2023

Whether it's excess fat leading to cancer, heart trouble and diabetes, nasty bacteria leading to food poisoning,or unknowns surrounding the use of agricultural chemicals leading to fear, people are worrying about what they eat. Meals, it seems, are no longer gatherings at which friends and family share stories and food, but a crisis of introspection and guilt.

People are concerned about the quality of the food they eat. Producers and others want to bring the best knowledge to bear on any decision or action involving food. But the ability to apply science-based solutions to food safety and other food-related challenges is intricately dependent on issues of public perception, the regulatory environment, fairness, accountability and, most importantly, trust.

On-farm food safety programs are an action, an appropriate risk management strategy, to demonstrateto consumers that producers are cognoscent of their newfound concerns about microbial food safety, and to demonstrate that producers and others in the farm-to-fork continuum are working to reduce levels of risk. Because when the next outbreak comes - and microorganisms can adapt and evolve to any food production and distribution system that is created - producers need to demonstrate due diligence to minimize potential losses.
Atresia coli in calves
Authors: Constable P. D. , Huhn J. C. , Morin D. E. , Nelson D. R.
Published: March 2023

Atresia coli is a congenital abnormality in cattle that is lethal without surgical correction. Although the condition has been reported predominantly in the Holstein-Friesian breed, the inheritance of atresia coli remains controversial and not completely understood. A systematic review of published cases and hospital-based case-control study were undertaken to evaluate breed as a risk factor for atresia coli in cattle, and to determine the best method for surgical management. Systematic review of 37 published studies indicated that atresia coli has been diagnosed in 10 cattle breeds and 12 countries, with the marked preponderance of cases occurring in Holstein-Friesian calves. Epidemiologic analysis indicated that Holstein-Friesian cattle were at significantly greater risk for the condition than all other dairy cattle breeds (P < 0.0001) and all other cattle breeds (P < 0.0001). Atresia coli probably occurs secondary to vascular insufficiency of the developing colon in calves. Holstein-Friesian cattle are predisposed to atresia coli, probably because their developing colon grows at a faster rate and/or to a greater extent than that in other cattle breeds. Early or vigorous palpation per rectum of the amniotic vesicle appears to increase the risk of atresia coli in a predisposed fetus, probably through palpation-induced damage to the rapidly developing colonic vasculature. Surgical correction of atresia coli had a poor overall success rate (short term survival rate was <50%) and long term survival rate (<35%). Because of the poor survival rate, expense, and potential for propagation of a genetic defect, definitive surgical correction should not be routinely performed on affected Holstein-Friesian calves.
Pooled faecal samples compared with individual samples for detection of Salmonella in cattle
Authors: Kivela Sirkka-Liisa , Ruoho Olli , Seun Eija , Hintikka Eeva-Liisa
Published: March 2023

The modified ISO 6579:1993 method was used to examine in parallel the presence of Salmonella in 4579 individual faecal samples and 210 pooled samples from 130 herds of cattle. 25 clinically or subclinically S. infantis-infected herds were detected. Positive herds were examined once a month for 7 months. 112 pooled samples and individual samples, respectively, were negative. 88 pooled samples were Salmonella-positive. Ten negative pooled samples contained faeces from animals which were found to be Salmonella-positive in individual sampling. Nine of these false negative pooled samples contained faeces from more than 20 animals and all contained relatively few Salmonella-positive animals. These results indicated that Salmonella was reliably detected in pooled faecal samples of a maximum of 20 animals (Kappa test 0.98).
Breeding programs for dairy herds using prostaglandin F2α products to save labor
Authors: Seguin B. , Momont H. W. , King V. L. , Johnson D. G. , Marx G. , Otterby D. E.
Published: March 2023

Three reproductive management systems designed to use prostaglandin F2α (PGF) to save labor needed for estrous detection and artificial insemination (AI) were compared to conventional dairy herd reproductive management to evaluate their potential to maintain herd reproductive performance. The four experimental groups were: (1) CONTROL = daily estrous detection for AI with no PGF intervention, (2) Appointment (APPT) AI = double PGF injection at a 12-day interval followed by single appointment AI at 72 hrs for first AI, with repeat AI based on estrous detection, (3) 7-DAY = weekly (Monday) PGF injection for all cows ready for first or repeat AI with AI based on estrous detection which occurred only four days (Wednesday through Saturday) of each week, and (4) 21-DAY = repeating 21-day blocks of 13 days of AI based on estrous detection with PGF given on day 8 to cows yet to be inseminated and 8 days with no estrous detection or AI. All cows in all groups became eligible for breeding after a voluntary waiting period (VWP) of 54 days.
Effect of timing of tilmicosin metaphylaxis on control of bovine respiratory disease and performance in feeder cattle
Authors: McClary David , Vogel Gary
Published: March 2023

Four-hundred steer and bull calves at high risk of contracting bovine respiratory disease (BRD) were included in a 28-day study to evaluate various tilmicosin metaphylaxis programmes for the control of BRD in feeder cattle. The trial animals, which averaged 473 lb at purchase, came from multiple auction markets in the southeast USA over a 3 day period and were transported to a collection facility in West Point, Mississippi for treatment assignment. Following treatment assignment calves were randomly loaded onto trucks and transported to a research facility in Canyon, Texas. Calves were blocked by day of purchase and randomly assigned to one of four treatments in a randomized complete block design: (1) non-medicated controls, (2) metaphylactic treatment with tilmicosin at the time of treatment assignment (pre-shipment treatment), (3) metaphylactic treatment with tilmicosin at the time of processing at the research facility (post-shipment treatment), or (4) metaphylactic treatment with tilmicosin at the time of treatment assignment (pre-shipment) and 72 hours later (post-shipment) at the research facility (combination treatment). Tilmicosin was administered at 4.5 mg per lb (10 mg/kg) BW (7.1 ml) based on the average purchase weight. Data were analysed by analysis of variance using the General Linear Model procedure of SAS. The model included treatment, replication, and treatment x replication as sources of variation. The BRD morbidity rate was reduced in all tilmicosin metaphylaxis treatment groups as compared with controls (54, 29, 15, and 15% for treatments 1 through 4, respectively). Furthermore, BRD morbidity was reduced in the post-shipment and combination treatment groups compared to the pre-shipment treatment group. All calves experiencing clinical BRD during the trial were treated with tilmicosin at 4.5 mg per lb (10 mg per kg) BW, by subcutaneous (SC) injection. There was no difference between treatment groups in the treatment success rate for animals treated for BRD with tilmicosin. Bovine respiratory disease mortality was higher in the combination treatment group compared to the pre-shipment and post-shipment treatment groups (2, 0, 0, and 4% for treatments 1 through 4, respectively). There was no difference in average daily gain (ADG), dry matter intake, or feed/gain among any of the treatment groups during the 28-day study. Results from this study confirm that metaphylactic use of tilmicosin is an effective tool to control BRD in feeder cattle. Tilmicosin administered at the time of arrival processing (post-shipment) was superior to pre-shipment treatment. Combination treatment (both pre- and post-shipment) with tilmicosin did not further decrease BRD morbidity when compared to post-shipment treatment alone.
Method for recording pulmonary lesions of beef calves at slaughter, and the association of lesions with average daily gain
Authors: Bryant Lonty K. , Perino Louis J. , Griffin Dee , Doster Alan R. , Whittum Thomas E.
Published: March 2023

A method to record lung lesions in commercial packing plants was developed as part of this observational study. Data from calves born and reared at the Roman L. Hruska U.S. Meat Animal Research Center (MARC) were used to develop the scoring method. The method was then applied to calves from three feedlots in the private sector. Lung lesion rates in MARC calves at slaughter ranged from 31 to 66% by sire line and feedlot pen. Lesions at slaughter were associated with a decrease of 0.057 lb in average daily gain (ADG). Lesions were grouped into categories: lesions that were sequela to cranial ventral bronchopneumonia (CVBP), other lesions, and no lesions. This grouping resulted in CVBP lesions being associated with a 0.073 lb reduction in daily gains, and the effect of other lesion types were not significant. Neither lobar location nor the amount of lesion present was associated with daily gains. Clinically diagnosed respiratory disease was not associated with increased frequencies of lesions at slaughter. Lung lesion rates in calves from the private sector ranged from 33 to 77% at the pen level. 30% of these calves had CVBP type lesions at slaughter that were associated with a decrease in ADG. There was a significant interaction between feedlot pen and CVBP type lesions, with an overall effect on ADG ranging from a reduction of 0.14 lb to 0.65 lb.
Repeat breeder cow
Authors: Levine H. D.
Published: March 2023

Cows that fail to become pregnant after 3 inseminations may be termed repeat breeders (RBs).This paper reviews the incidence, economics, etiology and management of the RB cow. The incidence of RB in U.S. dairy herds is approximately 20% and depends on herd conception rate. Factors resulting in repeat breeding are discussed. Repeat breeders experience increased failure of fertilization due to tubal pathology and suboptimal breeding management. Increased embryonic mortality is evident in RBs before maternal recognition of pregnancy. Uterine environment and uterine asynchrony may play important roles in reducing fertility in RBs. Non-specific uterine infections are not major causes of RB but specific viral and bacterial agents known to cause early embryonic death can play roles. Clinical management of RBs should begin with record analysis and thorough reproductive examination. When no specific pathology is detected, prognosis for fertility is guarded but use of GnRH at time of insemination, synchronization of ovulation or uterine lavage maybe attempted. Invaluable animals, embryo transfer or oocyte aspiration with IVF and IVC has resulted in genetic recovery.
Thirty-Second Annual Conference of the American Association of Bovine Practitioners
Authors: American Association of Bovine Practitioners
Published: March 2023

Description of the Annual Conference of the American Association of Bovine Practitioners (32nd : 1999), officers, district news, events, awards, and other news.
Survey of Selected Risk Factors and Therapeutic Strategies for Parasitism on Milk Production Response of Lactating Dairy Cattle
Authors: Leslie Ken , Jackson Amy , Duffield Todd , Dohoo Ian , DesCoteaux Luc , Hovingh Ernest
Published: March 2023

A recent review of studies on the effect of parasite control programs on productivity of lactating dairy cattle has reported positive, but variable, results. A conjoint analysis survey was conducted, using dairy industry professionals and practicing veterinarians, to estimate the impact of various management strategies on the control of parasites on milk production in dairy herds. The results of the survey suggested positive associations of confinement housing systems, replacement heifer treatment programs and cow treatment programs with milk production. Spreading manure on pastures and not using a treatment program in heifers were determined to have the most important negative association with milk production. The survey responses also suggested that topical treatment for external parasites, and strategic use of endectocide products in the prepartum period, would have a positive effect on production. Areas of high priority for research on the association between parasites and productivity in dairy cattle would include the relative impact of whole herd versus strategic lactation cycle treatment programs.
Case report
Authors: Washburn Kevin E.
Published: March 2023

A 550 lb steer was presented with a history of anorexia, depression, "stiffness", and scant feces. Physical examination revealed a normal rectal temperature, increased heart and respiratory rates and abdominal distension. The initial attempt to examine the steer per rectum was unsuccessful. Laboratory findings were normal except for increased protein in the abdominal fluid. A second examination of the abdomen per rectum revealed a tight, fibrous band extending from the right internal inguinal ring to the pelvic floor, which had entrapped portions of the small intestine. An exploratory laparotomy was done using the right paralumbar fossa approach. The tight fibrous band was found to be a remnant of the vas deferens. The band was exteriorized and cut with scissors. Post-operative recovery was uneventful and the steer was marketed months later at his projected market weight.
Case report
Authors: Dzuba Lynne M.
Published: March 2023

A seven-year-old pluriparturient Holstein cow was presented because of failure to complete parturition. On physical examination a 270-degree, counterclockwise uterine torsion was found. Attempts to correct the torsion via the vagina were unsuccessful as the fetus would immediately return to the dorso-ileal position when released. A left flank laparotomy was performed and the 270- degree counterclockwise torsion was confirmed. One hind limb has perforated the uterine wall and was the cause of failed attempts to correct the torsion vaginally. The live term, male fetus was delivered by cesarean section. The uterus and body wall were routinely closed and the cow was treated for shock. She died 12 hours post-operatively.
Johne's Disease Update
Authors: Step D. L. , Streeter Robert N. , Kirkpatrick John G.
Published: March 2023

Mycobacterium paratuberculosis causes a granulomatous enteritis in cattle that is commonly known as Johne's Disease or paratuberculosis. Young calves acquire the infection in utero or within the first few months of age by the fecal-oral route. Available diagnostic tests have limitations, but when used with appropriate management practices, a control/eradication program can be designed to meet the needs of the producer. Control programs are aimed at minimizing or eliminating exposure to the organism. There is no curative treatment for paratuberculosis.
Forces Exerted by Hydraulic Cattle Chutes
Authors: Perino Louis J. , Parker David B. , Brown Renee , Jeter Michael B.
Published: March 2023

To describe the magnitude and variability of forces generated, we measured peak forces at nine different locations in hydraulic chutes used for cattle restraint. The headgate, middle of the chute, and tailgate were each measured at 18, 34, and 48 inches from the chute floor using a 3,000 lb capacity, high accuracy S-beam load cell. Peak forces generated by hydraulic chutes ranged from a low of approximately 100 lb to a high of over 3000 lb. There were large variations in forces observed within and between facilities, with the coefficient of variation on chute forces across all chutes at approximately 50% for all positions assessed. At 34 inches from the floor, 43, 14, and 29% of chutes generated less than 600 lb of force at the headgate, middle, and tailgate, respectively, while 29, 50 and 21 % of chutes generated greater than 1000 lb of force at the headgate, middle, and tailgate, respectively. There is a large amount of variability in forces generated by hydraulic chutes used for cattle restraint. Some chutes generate forces potentially hazardous to cattle.
AABP News and Conference Highlights
Authors: Bovine Practitioners American Association of
Published: March 2023

Description and highlights of the 33rd Annual Convention American Association of Bovine Practitioners, 2000 and information about officers, district news, events, awards, and other news.
Methods to Monitor New Intramammary Infections in Dairy Cows Using Somatic Cell Count Data
Authors: Kristula M. A.
Published: March 2023

This report provides methods to monitor the number of new mammary infections in dairy cattle using monthly Dairy Herd Improvement somatic cell count data. The new infection rate on a monthly basis is defined as the number of cows over linear score 4 for the first time, divided by the total number of cows at risk. The cumulative analysis of days-in-milk when new infections occur allows for quantification of the highest risk period by days-in-milk for the occurrence of new infections. The methods outlined enable some statistical inferences to be made about the overall mammary infection rate, and the greatest time period of risk for new infections. This information can be used to evaluate management decisions aimed at lowering the number of new mammary infections.
Case report
Authors: Belloli Angelo , Carli Silvano , Pravettoni Davide , Proverbio Daniela , Giangaspero Massimo , Lauzi Stefania , Bonizzi Luigi
Published: March 2023

A Holstein-Friesian dairy cow naturally infected with Mycobacterium paratuberculosis, and suffering from enterocolitis, was treated orally with a combination of rifampin, pyrazinamide and streptomycin (30, 50 and 25 mg/kg/day, respectively) for seven months. Clinical and hematological evaluations were regularly performed beginning on the day of admission, extending throughout treatment and continuing until four months after therapy was terminated. Therapy was associated with normalization of hematological and serum biochemical parameters, and a 440 lb (200 kg) weight gain. This positive effect was observed during the entire treatment period and persisted for nearly four months after the end of therapy. Microscopic examination of Ziehl-Neelsen stained fecal samples was negative for M. paratuberculosis from the second day, and remained negative until the fourth month after therapy was completed. Fecal cultures remained positive for M. paratuberculosis throughout the observation period. The cow was harvested four months after cessation of therapy. These observations suggest that chemotherapy results in improvement in clinical signs, and might induce a transient reduction of Mycobacterium paratuberculosis shedding. It did not eradicate the infection or eliminate shedding of the organism.
Case report
Authors: Emery Kathleen , Oetzel Garrett
Published: March 2023

Polioencephalomalacia (PEM) is a neurologic condition in ruminants that can be caused by several dietary factors including water deprivation-sodium ion toxicosis, lead poisoning and high sulfur intake. Three month old calves on a 1500-cow dairy experienced neurologic problems during three separate episodes. The morbidity rate approached 75% each time. Based upon post-mortem examination, three of the affected calves were diagnosed with PEM. The history revealed a change in the formulation of the pelleted feed four days prior to the initial outbreak. Wet chemistry analysis of the pelleted feed revealed a sulfur content of0.56% (dry matter basis), which was considered to be the cause of the PEM outbreak.
Effects of Single Administration of Half-dose Injectable Doramectin, Full-dose Injectable Doramectin, or Fenthion on Fecal Egg Counts, Growth Performance and Carcass Characteristics in Cattle
Authors: Edwards Thomas A. , MacGregor Scott , Lechtenberg Kelly F.
Published: March 2023

This clinical trial was designed to compare the effects of a single administration of half-dose doramectina, full-dose doramectin, or fenthionb only on growth performance, hot carcass weight, carcass quality grade and fecal egg count in a group of cattle of western US origin and finished in eastern Nebraska. Two hundred ninetyfive crossbred steers (mean weight 667 lb; 303 kg) were purchased from auction barns in California, processed and allocated to the study in Idaho, and finished in a commercial feedlot in eastern Nebraska. At arrival to the backgrounding yard in Idaho, the calves were randomly assigned to one of three treatment groups: 1) fenthion only (0.5 oz/cwt); 2) half-dose (0.55 ml/cwt) of injectable doramectin; or 3) full-dose (1.1 ml/cwt) of injectable doramectin. Cattle in the fenthion treated group were poured with fenthion for ectoparasite control. At arrival, individual weights were recorded and fecal samples collected and assayed to determine nematode egg counts. Individual cattle weights and fecal samples were collected and recorded again when cattle were reimplanted (day 76). Carcass data were collected at harvest and individual live weights were calculated from individual carcass weight and group dressing percentage. In this study, there was significant improvement (p = 0.022) in hot carcass weight (HCW) in cattle administered full-dose doramectin as compared to cattle administered half-dose doramectin or fenthion pour-on only. Average daily gain (ADG) was greater in the group treated with full-dose doramectin than in the fenthion only group (p = 0.016). Significant differences in fecal egg counts were not found between experimental treatment groups (p = 0.078).
Critical Control Points in Beef Heifer Development
Authors: Lehman Fred D.
Published: March 2023

Critical control points (CCPs) are the important thresholds that provide opportunities to measure the success of a process. The appropriate application of CCP in a heifer development program will provide insight as to the success or failure of management's efforts to introduce productive females into the herd. The first CCP occurs at breeding and reflects how appropriately the heifer's growth and phenotype have satisfied the physiologic demands of reproduction. Breeding management and breeding efficiency rates are examined at the second CCP, which is measured at the first pregnancy examination. The third CCP, measured at calving, gives an indication of the success of the nutritional plan and losses associated with pregnancy and the perinatal period. The fourth CCP, measured at the second season pregnancy exam, is a critical evaluation of how the heifer has fared with the cumulative stress of reproduction and lactation.
Book News and Abstracts
Authors: Bovine Practitioners American Association of
Published: March 2023

Description of new books of interest to bovine practitioners.
Use of daily postpartum rectal temperatures to select dairy cows for treatment with systemic antibiotics
Authors: Kristula Michaela , Smith Billy , Simeone Aliza
Published: March 2023

This retrospective study analysed descriptive statistics on daily rectal temperatures of 1042 dairy cows taken for 10 days postpartum on one farm in southeastern Pennsylvania, USA, from May 1998 to February 2000. Cows were classified as NORMAL if they did not have a retained placenta, dystocia, metritis, or mastitis event and received no systemic antibiotic treatment for the first 10 days postpartum. NORMAL cows had average daily temperatures below 102.0°F during days 1 through 10 postpartum. Cows with either retained placenta, metritis, dystocia or mastitis tended to have temperatures greater than 102.0°F during days 2 through 8 postpartum. All cows had the lowest temperatures during the first two days postpartum. Those requiring systemic antibiotic treatment had their highest temperatures on days 3 through 6 postpartum. Because there were no differences in daily postpartum temperatures of normal cows by lactation, the same criteria could be used to select primiparous and multiparous cows for treatment with systemic antibiotics. Finding one rectal temperature greater than 102.0°F or 102.5°F would not be sufficiently discriminating to decide to treat with antibiotics because 48% of NORMAL cows had at least one temperature greater than 102.5°F during the first ten days postpartum. Cows with average temperatures greater than 103.5°F had a significant average 1.0°F decline in temperature the day after systemic antibiotic treatment was started. Daily temperatures should be taken for at least seven days postpartum.
Comparison of neutralizing antibodies to type 1a, 1b and 2 bovine viral diarrhea virus from experimentally infected and vaccinated cattle
Authors: Jones Lisa , Van Campen Hana , Xu Zhi-Chang , Schnackel John A.
Published: March 2023

Serum neutralizing (SN) antibody titres to cytopathic (cp) type 1a, type 1b and type 2 bovine viral diarrhoea viruses (BVDV) were determined for yearling, crossbred beef heifers immunized with a modified live cytopathic type 1a BVDV vaccine, or experimentally infected with a noncytopathic (ncp) type 1b or a ncp type 2 BVDV. The results indicate that type-specific and cross-reactive SN titres are usually found to all three test viruses in an individual animal, with the highest SN titres to the same genotype of BVDV as the challenge or vaccine virus. Exceptions to this trend were found in individual animals, however, emphasizing the importance of comparing the SN titres for several animals in a herd. Determining SN titres to the three BVDV genotypes may help veterinarians distinguish the BVDV genotype involved in a herd infection from antibody titres due to vaccination.
Onset of serum antibodies to Pasteurella (Mannheimia) haemolytica following vaccination with five commercial vaccines
Authors: Confer Anthony W. , Montelongo Marie , Brown M. J. , Fergen B. J. , Clement J. C.
Published: March 2023

The purpose of this study was to compare the antibody responses of cattle vaccinated with one of five commercial non-living P. haemolytica vaccines during the first two weeks after a single vaccination. Antibodies to surface antigens (whole cells) and to the leukotoxin (LKT) were quantified at Days 7 and 14 after vaccination. In addition, antibodies to specific P. haemolytica whole cell protein antigens were determined by immunoblots using sera from vaccinated and control calves. Three hundred pre-weaned, mixed beef breed steers and heifers, greater than three months old, were equally divided among five vaccinated and one placebo groups. Cattle were subcutaneously injected with one of the following commercial P. haemolytica vaccines: One Shot, One Shot Ultra 8, Pyramid 4+Presponse SQ, Pulmo-guard PH-M or Poly-Bac B 1. Antibody responses to both LKT and whole cells were highest on Day 7 for One Shot and One Shot Ultra. By Day 14, Pulmo-Guard stimulated serum antibodies to both antigen preparations that were equivalent to those for One Shot and One Shot Ultra. Serum antibodies to LKT and whole cells were detected in the Pyramid/Presponse- and Poly-Bac 1 - vaccinated groups; however, those responses were not significantly different from the placebo group. Each vaccine, except for the Pyramid 4/Presponse - vaccinated group, stimulated antibodies to similar P. haemolytica somatic proteins, particularly at 200, 100, 60-70, 45, 35 and 25 kDa. Sera from the Pyramid 4/Presponse-vaccinated group recognized fewer protein bands, mainly those at 200, 70-75, 48 and 35 kDa. In conclusion, various commercial vaccines induced differences in the rapidity and the intensity of serum antibody responses to P. haemolytica whole cells and LKT.
Evaluation of Salmonella shedding in cattle fed recycled poultry bedding
Authors: Capucille Dawn J. , Poore Matthew H. , Altier Craig , Rogers Glenn M.
Published: March 2023

Recycled poultry bedding (RPB), contaminated with Salmonella, was fed to beef calves to determine if it would increase the prevalence of detectable Salmonella faecal shedding. 60 Angus crossbred steer calves were placed on balanced rations containing Salmonella-contaminated recycled poultry bedding that had been properly or improperly stacked, or fed a control diet for an 84-d growing phase. After the growing phase, the calves were transported (for 12 h) to simulate shipping stress and then fed a single finishing diet. Faecal samples were collected from each calf and cultured for Salmonella prior to the start of the trial, every 14 days during the growing phase, 24 hours after transport and every 28 days during the finishing phase. At the end of the finishing phase, scrapings from the ileocaecal mucosa were collected at the abattoir and cultured. Dietary components and total mixed rations were sampled and cultured weekly for Salmonella. Other than the poultry bedding at delivery, none of the dietary components or calves were culture-positive for Salmonella at any time during the feeding periods or after transport. One calf that had been on a RPB diet during the growing phase was positive for Salmonella norwich at postmortem collection; however, it was not established that this was the same serotype of Salmonella cultured from the RPB. We conclude that feeding a known Salmonella-contaminated feed source as a part of a balanced ration did not increase the prevalence of detectable Salmonella shedding in calves over the published prevalence.
Sudden death of three calves within two weeks of vaccination and castration
Authors: (Reynolds) Mills Sarah M.
Published: March 2023

Three male beef calves, 3-4 mo of age, died a few days after vaccination and castration. Because the pasture had been used several years without incident by the producer for calving, environmental causes were low on the differential diagnosis list. Because there was not an opportunity to examine the calves ante-mortem and necropsy findings were unremarkable, the practitioner relied on the producer?s description of clinical signs, then worked with the producer and pathologist to reach a definitive diagnosis of lead poisoning. The blood lead level in one calf that died was 4.3 ppm, and the kidney lead level was 101 ppm. Economic concerns were compounded due to potential exposure of a number of cows in the first trimester of pregnancy.
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 (35th : 2002), officers, district news, events, awards, and other news.
Case report
Authors: Washburn Kevin E. , Streeter Robert N.
Published: March 2023

A five-year-old, 2000 lb (909 kg) beef bull was presented to the Oklahoma State University Food Animal Clinic because of weight loss during the previous eight weeks, and lameness and increasing recumbency of two weeks? duration. Physical examination revealed a subsolar abscess, oral lesions, mild diarrhea, modest generalized lymphadenopathy and an enlarged left scrotum. Further diagnostic testing revealed liver fluke infestation, scrotal hydrocele, ascites and a positive gp-51 bovine leukemia virus serology. The ascites, weight loss, diarrhea, lymphadenopathy and hydrocele were attributed to migration of immature liver flukes. The lameness and recumbency were caused by a subsolar abscess and, therefore, unrelated to the primary problem. Bovine papular stomatitis was suspected to have caused the oral lesions, due to their physical appearance and rapid resolution. The bull was treated twice, at eight- week intervals, with ivermectin which contained clorsulon. Body condition markedly improved over the next 24 days, and the scrotal hydrocele resolved.