bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of an internal teat sealer used in conjunction with intramammary antibiotics on the cure of intramammary infections during the dry period
Authors: Sanford Carolyn J. , Keefe Greg P. , Dohoo Ian R. , Barkema Herman W. , Dingwell Randy T. , Leslie Ken E.
Published: March 2023

The objective of this study was to determine if an internal teat sealer used in addition to dry-cow antibiotics would have a beneficial effect on the elimination of intramammary pathogens during the dry period. In total, data from 425 culture-positive quarters from 270 Holstein-Friesian dairy cows were utilized in this trial. Milk samples were collected aseptically two weeks prior to the anticipated dry-off date, on the dry-off date and again at 1-8 days-in-milk. Infected quarters were randomly assigned to treatment with both an internal teat sealer and a dry-cow antibiotic, or a dry-cow antibiotic alone. Quarters were defined as cured if the pathogen(s) isolated in the dry-off sample were not isolated in the postpartum sample. There was no difference in overall bacteriological cure between the two treatment groups, internal teat sealer and dry-cow antibiotic versus dry-cow antibiotic alone. Similarly, no significant differences were observed for cure of either major or minor pathogen infections.
Food animal clinical course evaluations are influenced by student career goals
Authors: Tyler Jeff W. , Nagy Dusty W. , March J. Zac , Schultz Loren
Published: March 2023

In response to concerns expressed by faculty members that the preponderance of students interested in small animal practice negatively impacts results of food animal course evaluations, a study was undertaken to examine the relationship between student career goals and student evaluations of courses and course content. All student evaluations available for a food animal medicine, surgery and production medicine clinical course taught at the University of Missouri College of Veterinary Medicine from January 23, 2002 to June 7, 2005 were compiled. One component of the survey was student perceptions of the course and course content. These perceptions were linked to student career goals. Median scores for course content differed significantly among students with small animal, mixed animal and large animal career goals (P=0.002). Specifically, the grade for course content differed among students with an expressed career in small animal practice and students with an expressed career in large animal practice (P<0.05). Median scores for the course in general also differed significantly among the three defined groups (P=0.044); however, none of the specific pair-wise comparisons were significant (P>0.05).
Comparison of 3-, 5-, and 7-day post-treatment evaluation periods for measuring therapeutic response to tilmicosin treatment of bovine respiratory disease
Authors: Carter Brandon L. , McClary David G. , Mechor Gerald D. , Christmas Rodney A. , Corbin Marilyn J. , Guthrie Carl A.
Published: March 2023

Three-hundred steer calves with clinical signs of bovine respiratory disease (BRD) and a rectal temperature of 104øF (40øC) or greater were enrolled in a 56-day study to evaluate the effect of a 3-, 5- or 7-day post-treatment evaluation (PTE) period on therapeutic response to tilmicosin. Trial calves (average weight 557 lb; 253 kg) were purchased from livestock auction markets in Colorado, Kansas, Oklahoma and Wyoming, and delivered to the trial site in Wellington, Colorado. Upon randomization to a treatment group, tilmicosin was administered at 4.55 mg/lb (10 mg/kg) of body weight. Three treatment groups were defined by the number of days (3, 5 and 7) post-treatment during which they were not eligible for retreatment for BRD. The 7-day PTE group had a significantly higher treatment success rate compared to the 3-day PTE group (P=0.05). The 3-day PTE group had a higher (P<0.05) first relapse rate than the 7-day PTE group, and a higher (P<0.01) second relapse rate than either the 5- or 7-day PTE groups. There were a total of five BRD-associated mortalities in the study; all occurred within the first eight days of the study. Results from this trial suggest that a 3-day PTE period following tilmicosin administration could result in an overestimation of treatment failure rates compared to a 7-PTE period.
Improving reproductive efficiency through the use of reproductive tract scoring in a group of beef replacement heifers
Authors: Pence Mel , Ensley Doug , Berghaus Roy , Rossi Johnny , Wilson Tim , Cannon Patsie T.
Published: March 2023

This study investigated the potential improvement in reproductive efficiency through reproductive tract scoring (RTS) of heifers 30-60 days prior to breeding. Between 2000 and 2004, the RTS of 1986 heifers (mean age of 395 days) were determined in two locations in Georgia, USA as part of the Heifer Evaluation and Reproductive Development (HERD) project. These heifers were of similar age and were managed using comparable nutrition and management protocols. The Kaplan-Meier product-limit method was used to analyse the number of days from the start of the breeding period to conception for heifers with different RTS classifications. RTS was significantly associated with both time to conception and the proportion of heifers that conceived during the breeding period. The mean time to conception for heifers in the combined RTS 1 and 2 category (37.8 days) was significantly longer than for heifers with scores of 4 (19.7 days) or 5 (15.8 days), but not significantly different from heifers with RTS of 3 (29.2 days). The estimated percentages of heifers that would have conceived during a uniform 70 day breeding period were 94.6% of RTS 5, 91.2% of RTS 4, 87.6% of RTS 3, and 70.5% of RTS 1 and 2. This study indicates that reproductive tract scoring can be used to assist producers in the selection of heifers that will conceive at a higher rate and breed earlier during the breeding season.
Ultrasonographic distribution and duration of udder edema in post-partum and over-bagged dairy cows
Authors: Waller Kenneth R. , O'Brien Robert T. , McGuirk Sheila M.
Published: March 2023

The objective of this study was to determine the ultrasonographic distribution and duration of edema in the mammary gland of dairy cattle due to recent parturition or prolonged duration of not milking ("over-bagging"). Mammary glands of 74 post-partum cows were imaged ultrasonographically within 24 hours of parturition and every 48 hours until ultrasonographically negative for mammary gland edema for 96 hours. All post-partum cows were imaged 10-11 hours after last milking. Distribution of edema on ultrasonographic examination of the mammary gland was also mapped on 26 over-bagged cows at exhibitions. Sixty-eight of 74 (91.8%) post-partum dairy cattle had ultrasonographically detectable udder edema. Post-partum edema was centered at the ventral midline region at the junction of the udder and body wall between the subcutaneous abdominal veins. Edema persisted for an average of 14.7 days in the fore and 14.8 days in the rear quarters. No edema was detected after 22 days post-partum in any cow. In the fore udder of over-bagged cows, edema was centered on the peripheral vein mid-height on the lateral surface of the fore quarters. In the rear quarter, edema was centered in the mid to ventral aspect of the median crease. Average time since last milking in the "over-bagged group" was 19 hours, and average days-in-milk was 104 days. These two patterns of distributions are important for differentiation from injection-induced edema in show cows, and ultrasonographic differences between physiological and artificially induced edema are discussed.
Population Dynamics of Undifferentiated Neonatal Calf Diarrhea among Ranch Beef Calves
Authors: Smith David R. , Grotelueschen Dale M. , Knott Tim R. , Clowser Sharon L. , Nason Gail R.
Published: March 2023

We conducted a retrospective longitudinal study of a single population of calves from a grass-managed beef cattle system to determine which factors of time and subject explained the probability for calves to die from undifferentiated neonatal diarrhea. Data were collected from 402 beef calves at risk for undifferentiated neonatal calf diarrhea during a single calving season. Descriptive statistics from birth and mortality records were summarized, and factors of time and subject explaining the probability for calves to die of undifferentiated neonatal diarrhea were identified using a multivariable logistic regression model. Forty-eight of 402 calves (11.9%) died from undifferentiated neonatal diarrhea. Thirtynine of 47 calves with age-at-death information (83%) died between six and 15 days of age. The mean age at death did not change over the calving season, however, the weekly cumulative incidence of mortality increased as the calving season progressed. The probability of death was increasingly greater for calves born later in the calving season. The period of time a calf was born in the calving season (PcO.OOOl) and the age of the dam (P=0.006) explained the probability for a calf to die of neonatal diarrhea. Calves of two-year-old dams were more likely to die than calves of mature cows (OR= 5.79, P=0.003). The calves of three-year-old dams were intermediate in risk compared to calves of mature cows (OR=2.21), but not significantly different from calves from the other dam age-groups (P>0.10). The probability for calves to die was not explained by gender (P=0.68) or birth weight (P=0.43). Factors explaining mortality were age of the calf, age of the dam and point of time in the calving season the calf was born. Because the incidence of scours increased with the passage of time within the calving season, undifferentiated neonatal calf diarrhea might be prevented by designing beef calving systems which can maintain the more ideal conditions existing at the beginning of the calving season, which include low doses of pathogen exposure and fewer opportunities for older, highly-infective calves to transmit pathogens to younger, susceptible animals.
Effects of ear-notch sample handling on reliability of antigen-capture enzyme-linked immunosorbent assay testing for bovine viral diarrhea virus.
Authors: Funk Rebecca A. , Thomson Daniel U. , White Brad J. , Renter David G. , Rust Robert L.
Published: March 2023

Antigen-capture enzyme-linked immunosorbent assay (ACE) testing of skin samples obtained by ear-notching is commonly used to detect animals persistently infected (PI) with bovine viral diarrhea virus (BVDV). At times practitioners may not have access to phosphate buffered saline (PBS) solution for specimen storage as suggested by the ACE kit manufacturer. The first objective of this study was to observe the effects of storing ear-notch samples in varying amounts of PBS on ACE results. The second objective was to observe the effects of delayed time before the ear-notch sample was placed in PBS on the ACE results. Using virus isolation and immunohistochemistry, nine PI-positive and eight PI-negative calves were identified to obtain ear notch biopsies for the study. The amount of PBS used to store both positive and negative ear-notch samples was varied (1, 2, 4, 6, 8 and 10 mL) in the first trial. In the second trial, the addition of PBS to both positive and negative samples was delayed post-collection; phosphate buffered saline was added to ear-notch samples at 0, 1, 2, 4, 8, 12 and 24 hours post-collection. Following sampling and application of treatments, all samples were tested in duplicate for BVDV antigen following the guidelines of the ACE kit manufacturer. Although the S/P ratios were different among treatment groups in both studies (P<0.05), neither varying the amount of PBS added to the sample vial nor delaying the addition of PBS to the sample affected the outcome when testing positive or negative samples.
AABP Conference (2007): Minutes of the American Association of Bovine Practitioners
Authors: Bovine Practitioners American Association of
Published: March 2023

Description of the 2007 American Association of Bovine Practitioners Conference.
Case Report
Authors: Harvey Nathan D.
Published: March 2023

A two-year-old Angus bull presented with chronic weight loss and numerous masses in the submandibular, retropharyngeal and cervical regions. Physical examination and laboratory work were inconclusive, but needle aspiration and drainage of one of the masses revealed abscessation. The cause of the abscesses was unknown, and the bull was treated empirically with procaine penicillin for one week. His condition progressively deteriorated, therefore he was euthanized. Postmortem examination revealed chronic traumatic reticuloperitonitis (TRP) with extensive abscessation of the diaphragm, submandibular, retropharyngeal and cervical lymph nodes. Diagnosis in this case was elusive because the history and clinical signs were non-specific, and the peripheral lymph node abscesses were not considered a typical finding associated with TRP. It is unknown whether an antemortem diagnosis and more aggressive treatment would have resulted in a different outcome, given the chronicity of the case at presentation.
Case report
Authors: Thomson Daniel U. , Taylor Wade , Noffsinger Tom , Christopher Julia A. , Wileman Benjamin W. , Ragsdale John
Published: March 2023

In this study, tail tip necrosis in cattle fed in a confinement feedlot in Nebraska, USA was reported. One-time capacity of the feedlot was 80,000 head and reported prevalence of tail tip necrosis was 1%. Cattle were fed for 120-150 days before signs of the disease were noted. Thirty percent of affected cattle died because of failure to respond to therapy or were marketed prematurely because of chronic diseases. Abnormalities of the tail, joints, and lungs were found during post-mortem examination. Arcanobacterium pyogenes was isolated from all sampled sites. Tail tip necrosis is common in confinement feedlot facilities where cattle are housed on slatted floors and can lead to bacteremia and death.
Comparison of two Mannheimia haemolytica vaccination strategies in freshly weaned southeastern feedlot heifers
Authors: Rogers Karen C. , Portillo Thomas A. , Smialek Dennis E. , Miles Del G. , Lehenbauer Terry W. , Smyth Russell
Published: March 2023

A total of 1,017 southeastern crossbred heifer calves (average weight 572 lb; 260 kg) were used to determine the effect of administering Pyramid® 5 and Presponse® SQ (Fort Dodge Animal Health, Overland Park, KS) as two separate injections (SEP), or as a combination product (COMB), on health and performance in a commercial feedlot setting. There were no significant differences (P>0.05) between the two vaccine treatments for morbidity, mortality, or realizers. The SEP group had significantly greater weight gain (P=0.05) and average daily gain (P<0.01) at reprocessing (day 119). These differences subsided by harvest. Hot carcass weights, estimated live-weights and average daily gains at the end of the feeding period were similar among the vaccination groups (P>0.05).
Comparison of the BVDV, BHV-1, and BRSV anamnestic response to modified-live or inactivated vaccines in calves previously vaccinated with a modified-live virus vaccine.
Authors: Royan Grant
Published: March 2023

The objective of this study was to compare the serological responses in cattle initially vaccinated with a modified-live virus (MLV) vaccine containing infectious bovine rhinotracheitis (IBR) virus, parainfluenza-3 (PI3) virus, bovine viral diarrhoea virus type 1 (BVDV1), bovine viral diarrhoea virus type 2 (BVDV2), and bovine respiratory syncytial (BRS) virus antigens, and subsequently re-vaccinated with either the same MLV vaccine or inactivated vaccine with oil adjuvants, containing the same viral antigens. A group of 145 nursing calves received an MLV vaccine containing IBR, PI3, BVDV1, BVDV2, and BRSV at one to two months of age. The calves were re-vaccinated with the same MLV vaccine at weaning, three-and-a-half months later. Approximately five months later, 45 of these animals were randomly selected and assigned to one of three treatment groups. Twenty calves received inactivated vaccine with oil adjuvants (IBR, PI3, BVDV1, BVDV2, BRSV); 20 received the same MLV vaccine that they had received as calves (IBR, PI3, BVDV1, BVDV2, BRSV); and five controls received the MLV sterile diluent. Following final vaccination, the animals receiving the inactivated vaccine with oil adjuvants had the highest titre response (P<0.05) for IBRV, BRSV, BVDV1, and BVDV2.
Effect of testing and removal of feeder calves persistently infected with bovine viral diarrhea virus at the time of feedlot arrival and outcome on health, performance, and carcass characteristics
Authors: Stevens Elliot T. , Thomson Daniel U. , Reinhardt Christopher D. , Lindberg Nels
Published: March 2023

Twelve lots of auction-derived steers totaling 1,577 head with an unknown health history (initial body weight 660 lb [300 kg]) were used to investigate testing and removal of feeder calves persistently infected with bovine viral diarrhea virus (PI-BVDV) upon arrival at a single feedlot in central Kansas. Pens with a PI-BVDV calf present at arrival were considered exposed and were compared to pens of steers that arrived without a PI-BVDV calf in the group. Both exposed and non-exposed pens of steers were followed from arrival through harvest to investigate the impact of exposure on health, performance, and carcass characteristics of feedlot cattle. A significant difference in the morbidity between exposed (2.3%) and non-exposed (7.2%) cattle was found (P<0.01). No differences in retreatment or mortality rates were found between groups. Exposure to a PI-BVDV animal for less than 48 hours after arrival did not have an effect on performance parameters. There was an increased percentage of USD A yield grade 4 and 5 (P=0.01) carcasses in the exposed cattle, but no other differences in carcass characteristics were found between groups.
Evaluation of the risk of transmitting Staphylococcus aureus strains between replacement heifers through commingling at a heifer-rearing facility
Authors: Kristula Michaela A. , Fecteau Marie-Eve , Smith Billy I. , Young Sheri , Rankin Shelley C.
Published: March 2023

The objective of this study was to evaluate transmission of Staphylococcus aureus (S. aureus) strains between heifers that originated from either a high- or low-prevalence S. aureus herd after commingling at a heifer-rearing facility. Three to four-month-old heifers from the University of Pennsylvania (UPa) and the University of Delaware (UDel) were transported on a bimonthly basis and raised commingled at Eutgers University. Preliminary work established unique baseline strains of S. aureus at both universities prior to commingling, and a high prevalence of S. aureus at the UPa (22.4%) and a low prevalence of S. aureus at the UDel (2,7%). Composite milk, samples were obtained for culture of S. aureus from both universities three times in 2006 and four times in 2007. Strain typing of S. aureus was performed by pulsed-field gel electrophoresis. The predominant strain isolated at the UPa was not spread to the UDel when heifers were commingled. The prevalence of S. aureus at the first routine culture after parturition (3-124 days after parturition) in primiparous cows previously commingled was similar in both herds. Sixty percent of the S. aureus strains isolated from commingled primiparous cow from the UPa were strains that were also found in the lactating herd. The UPa had significantly more S. aureus infections acquired in later lactation or subsequent lactations in primiparous cows that had been previously commingled and negative at the first routine culture after parturition, and from cows previously not commingled, than the UDel. The predominant strain of S. aureus isolated in these cows was the same as the predominant strain isolated from the preliminary baseline cultures. In this study, three to four-month-old commingled heifers returned to their herd of origin two to seven months prior to parturition were more at risk of acquiring an endemic strain of S. aureus than strains they may have potentially been exposed to at a commercial heifer-rearing facility. In this study, low-prevalent strains not found in the lactating herd and isolated from primiparous cows at parturition were of minor importance, and the infected mammary gland of lactating cows was the major reservoir of S. aureus.
Characterization of Specific Passive Immunity Stimulated by Vaccination of Beef Cows Grazing Native Range with E. coli 0157:H7-SRP®
Authors: Wileman B. W. , Thomson D. U. , Olson KC , Pacheco L. A. , Jaeger J. R. , Burkhardt D. T. , Sandstorm J. , Emery D. A.
Published: March 2023

A total of 20 four-year-old, mixed breed cows were selected from the Kansas State University commercial cow-calf herd for this study. Cows were assigned randomly to one of two treatments: placebo, or E. coli O157:H7 SRP® (Epitopix LLC, Wilmar, MN) vaccination prior to calving. Serum total protein (TP) and serum Escherichia coli O157:H7 SRP® antibody levels (SRP) were measured pre-suckle and at set intervals post-suckle in calves. All 20 cows were negative for fecal shedding of E. coli O157:H7 throughout the study. Vaccination of cows had no effect on calf serum TP level (P > 0.05) compared to controls, however, length of time post-birth had a significant effect on calf serum TP levels (P < 0.001). Failure of passive transfer was recognized as early as six hours post-birth. A vaccine treatment by time post-birth interaction was observed for calf serum SRP® antibody levels (P < 0.01). Calves born to dams vaccinated with E. coli O157:H7 SRP® vaccine had elevated serum SRP antibody titers over time compared to placebo vaccinated calves. This study demonstrated that successful E.coli O157:H7 SRP® antibody passive transfer can occur in beef calves under natural range conditions. This could be the first step toward understanding life cycle immunization strategies against E. coli O157:H7 in cattle, and its effects on shedding of the organism by the animal at the time of harvest.
Trace Mineral Concentrations in Dairy Cattle with Rupture of Abdominal Artery Aneurysms
Authors: Lamm Catherine G. , Bischoff Karyn L. , Erb Hollis N. , Guard Charles L. , Hillebrandt Joseph R. , Thompson Belinda , Njaa Bradley L.
Published: March 2023

Rupture of abdominal artery aneurysm (AAA) in cattle is sporadic and typically affects adult Holstein dairy cows. In this retrospective study, liver concentrations of copper (Cu), iron (Fe), manganese (Mn), sulfur (S), and zinc (Zn) were evaluated using inductively coupled plasma atomic-emission spectroscopy. Up to three liver sample types (fresh/frozen, fixed, or paraffin embedded) were collected from 22 affected adult Holstein dairy cows (36 samples) and nine similarly aged control Holstein cows with histologically normal vessels that died from other causes (25 samples). There was no significant difference in the liver concentrations of Cu, Mn, S, and Zn between groups for any tissue sample type (all ~0.022; alpha=0.017). Liver Fe concentrations were lower in the affected animals for all tissue sample types (P~0.0067). Liver Fe concentrations were measured in 11 additional cattle that were exsanguinated at slaughter to determine if exsanguination results in low liver Fe concentrations. There was no significant difference between liver Fe concentrations in cattle with ruptured AAAs versus cattle that were exsanguinated, but both were significantly different from cattle that died from other causes (P=0.0066). This study found no significant differences in liver Cu, Mn, S, and Zn in cattle that died from AAA rupture compared to cattle that died from other causes. Significantly lower liver Fe concentrations in cattle that died from AAA rupture were apparently due to exsanguination.
Treatment of Candidal Mastitis in Two Holstein Cows
Authors: Roberson Jerry R. , Kalck Karen A.
Published: March 2023

Two Holstein show cows were presented for acute clinical mastitis in multiple quarters of five days and three weeks duration, respectively. The mastitis was classified as moderate to severe. Milk culture results revealed Candida rugosa and Candida krusei in pure culture, and California mastitis test (CMT) scores were a consistent 3 in all infected quarters. The cows were treated with intramammary miconazole (200 mg) every 12 hours for seven to eight total treatments. Milk cultures were collected and plated every 24 hours. A noticeable reduction in colony numbers during therapy was not evident. Miconazole was not an effective treatment for Candida rugosa or Candida krusei. An extensive review of the literature did not reveal any documented efficacious treatments for candida mastitis.
Improving health and productivity in Holstein dairy cows diagnosed with twins
Authors: Aceto Helen , Gallop Robert , Rieger Randall H. , Applyby Dina H. , Smith Billy I.
Published: March 2023

Holstein cattle diagnosed with twins pose difficult managerial decisions for dairy producers. Since there is no effective method to reduce the incidence of twinning, it is important to better understand how these metabolically challenged animals should be handled to maximize health and productivity. The objectives of this study were first, to develop a metabolic profile of Holstein cows carrying twins and second, to investigate how implementation of a simple on-farm management intervention affected cows with twins by comparing metabolic status, disease events, and milk production in animals subject to typical dry-cow management (control: low-energy diet from dry-off for five weeks, followed by a nutrient-dense ration for three weeks prior to calving) and those exposed to atypical feeding management (treatment: nutrient-dense ration for the entire eight weeks of the dry period). A total of 36 cows confirmed with twins by transrectal ultrasonography were randomly allocated to control (19) or treatment (17) diets. Cows in the treated group had a steady decline in body weight over the dry period, while cows in the control group maintained weight and then declined precipitously after the change in diet. There was no beneficial effect on disease events, and there was an unexplained negative impact on mastitis incidence. Cows in the treated group had significantly higher postpartum serum ?-hydroxybutyrate (P<0.0001) and mastitis (P=0.04) levels. Compared to other cows in the study herd, delivery of twins did not appear to affect milk production; within cows with twins there was no significant effect of diet on milk yields.
Retrospective analysis of risk factors associated with Johne's disease in Pacific Northwest dairy herds
Authors: Kinsel Mark , Mueller Bruce , Honstead John
Published: March 2023

Data from 407 dairy risk assessments completed as part of the United States Department of Agriculture's Voluntary Bovine Johne's Disease Control Program in Washington and Oregon from November 2003 to August 2007 were evaluated to determine what management practices were associated with herd Johne's disease status, and what range of these management practices were in use in Pacific Northwest dairies. Overall, assessment scores between Johne's disease-positive and Johne's disease-negative herds did not significantly differ. A multivariate logistic regression analysis of the 32 individual management practices and two herd-level variables included in the overall risk assessment score found nine factors significantly associated with whether the assessment veterinarian reported at least one case of Johne's disease in the previous year. These nine factors were: (1) herd size, (2) addition of new animals during the previous year, (3) stocking density of the calving area, (4) degree of manure build-up in the calving area, (5) presence of Johne's disease suspects in the calving area, (6) degree of manure soiling of udders and legs of cows in the calving area, (7) exposure of bred heifers to adult cow manure, (8) pasture-sharing by bred heifers and adult cows, and (9) degree of contamination of adult cow feed with manure.
Lung auscultation and rectal temperature as a predictor of lung lesions and bovine respiratory disease treatment outcome in feedyard cattle
Authors: DeDonder Keith , Thomson Daniel U. , Loneragan Guy H. , Noffsinger Tom , Taylor Wade , Apley Michael D.
Published: March 2023

Studies were conducted to examine the use of lung auscultation to predict bovine respiratory disease (BRD) case outcome in feeder cattle. In the first study, lung sounds were obtained and lung auscultation scores (LAS) were assigned by trained personnel. Antemortem physical examination and LAS were correlated with lung pathology and lung lesion scores at harvest. A field study was then conducted to determine LAS and case outcome in 4,341 feeder cattle treated for BRD. Lung auscultation score (P<0.01) and rectal temperature (P<0.01) were predictive of cattle with increased risk for BRD retreatment and mortality. The model-adjusted probability of a calf with a LAS of 2 requiring retreatment was 13%, whereas the probability of retreatment for cattle assigned a LAS of 9 was 63%. An increase in rectal temperature from 100.0 to 108.0°F (37.8 to 42.2°C) was correlated with a 266% increase in likelihood for retreatment for BRD. Risk of death from BRD increased nearly 2,200%, from 1.7% to 39%, as LAS increased from a score of 2 to 9. Risk of death due to BRD increased 196% as rectal temperature proceeded from 100.0 to 108.0øF. These studies demonstrate that lung auscultation score and rectal temperature could be useful to better predict BRD case outcomes in feeder cattle, and to facilitate targeted management decisions.
Evaluation of the onset of protective immunity from administration of a modified-live, non-adjuvanted vaccine prior to intranasal challenge with bovine herpesvirus-1
Authors: Burdett William W. , Bolton Michael W. , Kesl Lyle , Nordstrom Scott T. , Renter David G. , Roth James A. , Saltzman Ryan , Xue Wenzhi
Published: March 2023

Study objectives were to determine if subcutaneous administration of a modified-live, non-adjuvanted vaccine containing bovine herpesvirus-1 (BHV-1) at five, three, or two days pre-challenge, would reduce clinical signs, rectal temperatures, and viral shedding, and enhance serological response to BETV-1. Colostrum-deprived, neonatal calves (n=48) were randomly assigned to six treatment groups, each containing eight calves. Treatment groups were based on administration of vaccine (VAC) or saline controls (CON) and day of administration (day-5, -3 or -2) relative to intranasal BHV-1 challenge (day 0). Following challenge, calves were monitored for clinical signs, rectal temperature, seroconversion, and quantity of BHV-1 recovered by virus isolation from nasal swabs. Data for the evaluation period (days 4-14) were analyzed using multivariable statistics. Day-5 and -3 VAC groups had fewer (P less than 0.05) days of clinical illness compared to CON. Rectal temperatures were lower (P less than 0.05) during days 4-8 for each of the VAC groups as compared to combined CON groups. CON calves shed BHV-1 for more days than calves vaccinated on day-5 (P less than 0.01), day-3 (P=0.06), or day-2 (P=0.06). Mean concentrations of nasal BHV-1 also differed (P less than 0.05) between combined CON groups and each of the VAC groups during at least one study day. Calves in the VAC groups (median=10 days) seroconverted to BHV-1 (P less than 0.01) sooner than CON calves (median=14 days). This study demonstrated that the use of a non-adjuvanted MLV vaccine in neonatal calves can reduce the effects of BETV-1 challenge soon after vaccination.
Serological response to administration of Brucella abortus strain RB51 vaccine in beef and dairy heifers, using needle-free and standard needle-based injection systems
Authors: Pires Alda F. A. , Hoar Bruce R. , Sischo William M. , Olsen Steven C.
Published: March 2023

More than four million doses of Brucella abortus strain RB51 (SRB51) are administered in the United States every year. Accidental autoinoculation of humans has the potential to result in local and systemic symptoms; therefore, investigation of alternative delivery methods is warranted. The objective of this study was to compare the immunologic responses of four to eight-month-old beef and dairy heifers to vaccination with 1010 colony-forming units of SRB51, delivered either by standard needle-and-syringe system or needle-free injection system. There was no difference in the 30-day SRB51 antibody response to the two vaccination methods, and no difference in response between beef and dairy heifers. These data demonstrate that the humoral immune response of heifers to vaccination with SRB51 using a needle-free injection system is similar to the response obtained with a standard needle system. Further studies to define the cellular immune response and protection against infection are recommended before this administration method is considered for routine use.
Survey to describe current feeder cattle health and well-being program recommendations made by Feedlot Veterinary Consultants in the United States and Canada
Authors: Terrell S. P. , Thomson D. U. , Wileman B. W. , Apley M. D.
Published: March 2023

Feedlot veterinarians (n=23) representing 11,295,000 cattle on feed in the United States and Canada participated in a beef cattle health and well-being recommendation survey. Veterinarians were directed to an online survey to answer feeder cattle husbandry, health, and preventive medicine recommendation questions. The feedlot veterinarians visited feedyards in their practice 1.7 times per month. All survey participants train feedlot employees on cattle handling and pen riding, while only 13% of respondents speak Spanish. All recommend infectious bovine rhinotracheitis and bovine viral diarrhea vaccination for high-risk (HR), cattle at processing; other vaccines were not recommended as frequently. Autogenous bacterins were recommended by 39.1% of feedlot veterinarians for HR cattle, while metaphylaxis and feed-grade antibiotics were recommended by 95% and 52% of respondents, respectively, for HR cattle. Banding was more frequently recommended than surgical castration as calf body weight increased. Feedlot veterinarians recommended starting HR cattle in smaller pens (103 head per pen) and allowing 13 inches (33 cm) per head of bunk space. They further recommend that feedlots employ one feedlot doctor per 7,083 head of HR cattle, and one pen rider per 2,739 head of HR cattle. Ancillary therapy for treating respiratory disease was recommended by 47.8% of veterinarians surveyed; vitamin C was recommended (30.4%) twice as often as any other ancillary therapy. Cattle health risk on arrival, weather patterns, and labor availability were most important factors for predicting feedlot morbidity, while metaphylactic antibiotic, therapy antibiotic, and brand of vaccine were least important. This survey provides valuable insight into feeder cattle health recommendations by feedlot veterinarians in the US and Canada, and provides direction for future research.
Simulation model to estimate the relative economic value of three different open female management strategies among cow-calf herds in the United States
Authors: Nickell Jason
Published: March 2023

The sale of non-pregnant (open) females constitutes significant annual income for cow-calf producers, thereby requiring critical evaluation of multiple open-female management opportunities. A stochastic model was constructed to estimate the relative economic value of three common open female management practices within spring-calving beef herds consisting of 50, 300, and 600 head of cattle: (A) cull open females and replace with purchased pregnant females, (B) maintain open females in the herd, and (C) transfer open females into a fall herd. The temporal confines of each model reflect the time frame from the original open diagnosis until the time point of marketing first-generation calves produced by females from each respective management option. Based upon the model assumptions, Option C, on average, was a profitable endeavor regardless of herd size. Conversely, Options A and B were only sparingly profitable regardless of herd size. The market cost of purchasing pregnant replacement females, the cost of maintaining open females in the herd, and the cost of maintaining recently bred females through the winter months heavily influenced the estimates of Options A, B, and C, respectively. Based upon the confines of this model, these data suggest that regardless of evaluated herd size, the economic value of these open-female management options differ highly and are influenced by multiple factors. Therefore, the influential parameters of the outcome estimates, along with the management limitations of individual herds, should be considered when attempting to implement open-female management strategies among cow-calf herds.
Establishing reference ranges for sulfur concentrations in bovine liver and kidney samples
Authors: Taylor Jared D. , Bischoff Karyn L. , Hillebrandt Joseph R. , Morgan Sandra E. , Campbell Gregory A. , Lamm Catherine G.
Published: March 2023

Sulfur toxicosis is a common cause of polioencepha- lomalacia in cattle. Diagnosis requires comprehensive determination of dietary sulfur intake, which may not be possible if feedstuffs are no longer available. The goal of this study was to establish reference ranges for concentrations of sulfur in liver and kidney samples from cattle dying of causes unrelated to sulfur toxicosis. Samples were collected from 71 cattle and assessed for sulfur content using inductive coupled plasma atomic- emission spectroscopy. Cattle demonstrating neurologic signs or gross or histologic lesions of the brain were excluded from the study. Sulfur concentrations were calculated on a wet- and dry-matter basis. Values were examined for Gaussian distribution, and 95% confidence intervals were calculated using the mean for normally distributed values and the median for non-normally distributed values. The 95% confidence interval for liver sulfur was 4,522 to 9,982 ppm dry-matter (1,270 to 2,640 ppm wet-matter). The 95% Cl for kidney sulfur was 5,070 to 19,017 ppm dry-matter (1,187 to 2,918 ppm wet-matter). Correlation assessments suggest that dry- matter liver analysis may be the best defined and most reliable measure of sulfur burden. Additional research is needed to assess concentrations of sulfur present in the liver and kidney of cattle with sulfur toxicosis, the impact of dietary intake on tissue concentrations, and to determine whether postmortem sulfur measurement is a viable method of diagnosing sulfur toxicosis.
AABP Conference (2012): Awards
Authors: Bovine Practitioners American Association of
Published: March 2023

Description of the 45th American Association of Bovine Practitioners Conference, 2012.
Feedlot gastrointestinal parasite control and anthelmintic treatment options, a review
Authors: Edmonds Matthew D. , Johnson Edward G. , Edmonds Jenifer D.
Published: March 2023

Anthelmintics are an important tool in the feedlot industry. The goal of this review article is to provide the veterinary practitioner with a short summary of the important aspects of internal gastrointestinal parasite control in the feedlot. A review of economically significant gastrointestinal nematodes and the bovine liver fluke is provided, along with a discussion of treatment options and an anthelmintic efficacy assessment. Important aspects unique to the feedlot environment are addressed, including anthelmintic resistance and combination anthelmintic therapies.
Prevalence of Toxocara vitulorum in north-central Florida beef calves
Authors: Herron K. , Rae O. , Walden H.
Published: March 2023

A pilot study was conducted to determine the presence of Toxocara vitulorum in beef calves (Bos taurus) in north-central Florida. T. vitulorum is a nematode found in subtropical climates and considered to be rare in the United States. This parasite is thought to be endemic among water buffalo (Bubalus bubalis), and 1 small herd located in central Florida was included in the study. A Sheather's centrifugal flotation procedure to detect parasite ova was performed on all fecal samples collected (n=463). Beef calves sampled were less than 9 months of age, and all parasite ova observed in the flotation were noted. Although T. vitulorum was not found in any samples, many other parasite ova were present. Results of this study suggest that T. vitulorum is still rarely detected in north-central Florida.
Perception of lameness management, education, and effects on animal welfare of feedlot cattle by consulting nutritionists, veterinarians, and feedlot managers
Authors: Terrell S. P. , Thomson D. U. , Reinhardt C. D. , Apley M. D. , Larson C. K. , Stackhouse-Lawson K. R.
Published: March 2023

Consulting nutritionists (n=37), consulting veterinarians (n=47), and feedlot managers (n=63) from the United States and Canada participated in a feedlot cattle lameness survey. The majority of participants either manage or consult open-air, dirt-floor feedyard facilities (98.4%). Participants were directed to an online survey to answer questions pertaining to the incidence, management, perception, and economics of feedlot lameness. The median response of estimated lameness incidence in the feedyard was 2%, with a mode of 1% and a mean of 3.8%. Of survey participants, 81% estimated the contribution of lameness to total feedyard mortality as less than 10%. Similarly, 64% of participants estimated the contribution of lameness to the overall chronic and realizer loss in the feedyard to be less 10%. Forty-one percent of participants believed that 50% or more of cattle suffering from lameness require treatment. Participants indicated that footrot (42% of participants), injury (35% of participants), and toe abscesses (10% of participants) were the most common causes of lameness. The major contributing factors associated with non-infectious causes of lameness, such as upper limb injuries, toe abscesses or ulcers, and lacerations include cattle handling before and after arrival, pen surface and condition, and cattle temperament. Important contributing factors for infectious causes of lameness, such as footrot, were identified as pen surface and condition, cattle handling prior to arrival, and weather. Lameness was considered an animal welfare concern by 58% of participants. This survey provides insight into the perception of lameness and potential management factors which contribute to lameness through the perspective of multiple participants in feedlot cattle production systems.
Comparison of tildipirosin and tulathromycin for control of bovine respiratory disease in high-risk beef heifers
Authors: Compiani Riccardo , Baldi Gianluca , Bonfanti Maurizio , Fucci Daniele , Pisoni Giuliano , Jottini Stefano , Torres Siddartha
Published: March 2023

The purpose of this study was to compare the effectiveness of tildipirosin (TIP) to tulathromycin (TUL) administered at arrival to reduce morbidity in beef heifers (Charolais; n=785; age=11.1ñ1.9 months; average body weight=830.9 ± 78.48 lb (376.9 ± 35.6 kg)) at high risk of developing bovine respiratory disease (BRD). BRD morbidity was lower in the TIP group (TIP=6.8%; TUL=20.9%; P<0.01) over the feeding period. Animals in the TIP group had greater average daily gain compared to heifers in the TUL group (TIP=2.49 lb (1.13 kg); TUL=2.34 lb (1.06 kg); P<0.01). No differences were observed between groups for number and severity of lung lesions. In the present study, tildipirosin was more effective than tulathromycin in reducing BRD morbidity and improving growth performance in newly received beef heifers considered at high risk for BRD.
Health and performance of calves fed fresh colostrum from their dams compared to those fed stored colostrum from non-dams
Authors: Sims L. Judd , Pinedo Pablo J. , Donovan G. Arthur
Published: March 2023

The objective of this study was to assess the preweaning performance, health, and survival of calves fed fresh colostrum from their dams compared to calves receiving colostrum that was not from their dams, and had been stored frozen or refrigerated. A total of 182 Holstein heifer calves born during July and August 2010 at a north-central Florida dairy farm were included. Explanatory variables included colostrum source, adjusted colostrum score, total estimated IgG intake, time to colostrum feeding, and calf-serum total protein determination as a measure of colostral immunoglobulin absorption. Control variables comprised birth weight and dam parity number. Average daily weight gain (ADG) was not affected by colostrum source. Number of disease events was the only variable showing a significant negative association with ADG (P=0.001), but there was a tendency to significance for lower-birth weight to be associated with a higher number of disease events; P=0.08. Source of colostrum did not affect the number of disease events or the total number of days on treatment. Similarly, no significant association with calf mortality was found for colostrum source. Time to event analyses did not indicate any significant association between morbidity and mortality and any of the explanatory variables, including colostrum source. We concluded that colostrum source was not significantly associated with performance, health, and survival in this population of dairy calves.
Effects of two different doses of tilmicosin on pathogen load reduction and clinical outcome in feedlot cattle with naturally occurring bovine respiratory disease
Authors: Tripp Holt M. , Slosar Chelsey M. , Edmonds Matthew D. , Johnson Edward G.
Published: March 2023

The objective of this study was to determine the effect of 2 different doses of tilmicosin on pathogen load reduction and clinical outcome in feedlot cattle experiencing acute bovine respiratory disease (BRD). Cattle diagnosed with BRD were randomly assigned to 1 of 3 treatments: tilmicosin at 4.55 mg/lb (10 mg/kg) (TIL10); tilmicosin at 9.1 mg/lb (20 mg/kg) (TIL20); or untreated positive controls (POSCON). Cohorts were completed with an apparently healthy asymptomatic negative control (ASYMP). A total of 143 animals were enrolled in the study. Treating cattle with tilmicosin at 9.1 mg/lb (20 mg/kg) resulted in greater pathogen load reduction and equivalent or improved clinical response compared to a dose of 4.55 mg/lb (10 mg/kg). Cattle in the TIL10 and TIL20 treatments had reduced pathogen loads and increased survival rates compared to POSCON (P less than 0.05). The Mannheimia haemolytica numbers in the lungs were significantly reduced in the TIL20 treatment group on day 9 compared to TIL 10 (P less than 0.05). Survival of calves in the TIL10 and TIL20 groups did not differ (P greater than 0.05) from ASYMP, but was decreased (P less than 0.05) in POSCON calves compared to other treatments.
Case report
Authors: Miskimins Dale W. , Neiger Regg D. , Beaty James , Evans Timothy J. , Daly Russell
Published: March 2023

Twelve of 100 beef calves in central South Dakota had loss of tail switches and tail tips in the summer of 2014. The problem was noticed in July. Many of the calves were being raised to be show calves. All 12 affected calves had tail lesions and 3 were suffering from early lameness. Chemical analysis demonstrating multiple ergopeptine alkaloids in the creep feed suggested ergotism caused by Claviceps spp., specifically C. purpurea. Rapid identification of the cause of unusual distal extremity lesions is important to reduce suffering of affected animals and financial losses to owners.