bluuebunny/crossref_metadata_2025 huggingface dataset:
Case report
Authors: Buelow Kenn , Stewart Steve , Rapnicki Paul , Godden Sandra
Published: March 2023

An important role of the dairy consultant is to increase the profitability of their clients. Current and comprehensive production, nutrition, and financial records that can be analyzed daily are essential to track the effect of management changes on production and profitability. This paper uses a case study to describe the effect of changes in ration formulation and feed particle size on feed intake, feed costs, milk production, and profitability.
Prevention and Prediction of Displaced Abomasum in Dairy Cows
Authors: Geishauser T. , Leslie K. , Duffield T.
Published: March 2023

The objective of this article is to summarize studies that have been conducted on the prevention and prediction of displaced abomasum in dairy cows. Our findings indicate that displaced abomasum is a moderately heritable trait. Subclinical ketosis is a significant risk factor of displaced abomasum. Thus, displaced abomasum incidence might be lowered by genetic selection and by prevention of subclinical ketosis. To predict displaced abomasum, aspartate-aminotransferase activity in blood, B-hydroxybutyrate concentration in blood and milk, and the fat-protein-ratio in milk may be used. All of these parameters are frequently increased prior to the diagnosis of displaced abomasum.
Effects of Intranasal Versus Intramuscular Modified Live Vaccines and Vaccine Timing on Health and Performance by Newly Received Beef Cattle
Authors: Duff G. C. , Malcolm-Callis K. J. , Walker D. A. , Wiseman M. W. , Galyean M. L. , Perino L. J.
Published: March 2023

Two studies were conducted to evaluate the effects of viral vaccines and vaccination programs on health and performance of newly received beef cattle. In Exp. 1, two loads (120 steer and bull calves and 108 heifer calves for Load 1 and 2, respectively) were used to evaluate the effects of an intranasal vs an intramuscular IBR-PI3 vaccine on performance and health of newly received beef cattle. Treatments were: 1) no vaccine (Control); 2) an intranasal modified-live IBR-PI3 vaccine (IN); and 3) an intramuscular modified-live IBR-PI3 vaccine (IM). No treatment x load interactions were observed for performance data. For the 28-d receiving period, cattle given IN IBR-PI3 vaccine had greater daily gain (P < .05) than cattle given IM IBR-PI3 vaccine. No differences (P > .10) were noted for daily dry matter (DM) intake, however, the feed:gain ratio was increased (P < .05) for the IM group as compared to the IN group. No differences (P > .10) were noted among treatments in the percentage of cattle treated for BRD. In Exp. 2, 102 steer and bull calves were used to evaluate vaccine timing on health and performance of newly received calves. Treatments included: 1) no vaccine (Control); 2) no vaccine at processing, with an IM multiple antigen (IBR-PI3-BVD-BRSV) viral vaccine given on d 7; 3) intranasal IBR-PI3 administered at processing with IM IBR-PI3-BVD-BRSV vaccine given on d 7; and 4) IM IBR-PI3-BVD-BRSV vaccine administered both at processing and on d 7. No differences were noted for daily gain or daily DM intake during the 28-d receiving period. Feed:gain was improved (P < .10) for vaccinated calves as compared to controls. Results suggest that an intranasal IBR-PI3 vaccine might have beneficial effects on gain and feed efficiency compared with an intramuscular IBR-PI:-i vaccine. There was no advantage or disadvantage to delaying vaccination with viral vaccines until 7 d after arrival. In terms of overall 28-d gains and morbidity, vaccines did not enhance gains or effect morbidity, compared to negative controls. However, statistical power to detect differences was marginal in both experiments.
Book News and Abstracts
Authors: Bovine Practitioners American Association of
Published: March 2023

Reviews of books of intereste to bovine practitioners and abstracts from articles published in other veterinary journal.
Pasture deworming and (or) subsequent feedlot deworming with fenbendazole. II, Effects on abomasal worm counts and abomasal pathology of yearling steers
Authors: Taylor R. Flint , Bliss Donald H. , Brandt Robert T. , Nichols Wade T. , Rains Jerry R. , Hutcheson John P. , Smith Robert A.
Published: March 2023

734 steers, weighing 286 kg, were used during a 118-day grazing period, after which 640 were placed in a feedlot for finishing (average of 121 days, range of 111 to 133 days) to measure the main effects and interactions of 2 pasture deworming treatments (negative control, strategically dewormed with fenbendazole) and 2 feedlot deworming treatments (negative control, dewormed with fenbendazole) on faecal egg counts, abomasal worm counts and abomasal pathology. Seven to 10 abomasa from steers on each of the 4 pasture-feedlot treatments (pasture control-feedlot control; pasture control-dewormed in the feedlot; strategically dewormed on pasture-feedlot control; strategically dewormed on pasture-dewormed in the feedlot) were selected at slaughter to determine total worm counts, and to evaluate gross pathology and histopathology of the abomasal mucosa. Pasture deworming with fenbendazole (FBZ) in a strategic programme on days 0, 28 and 56 reduced adult and L4 and EL4 larval stages of Ostertagia ostertagi and adult and L4 stages of Trichostrongylus axei residing in the abomasum at slaughter. Feedlot deworming with FBZ reduced L4 and EL4 stages of O. ostertagi and adult and L4 stages of T. axei. An interaction between pasture deworming treatment and feedlot deworming treatment showed that pasture deworming had a significant effect on reducing the number of Trichostrongylus adult parasites, which was not further reduced by feedlot deworming. Strategic pasture deworming with FBZ followed by FBZ administration at the beginning of the finishing period reduced total O. ostertagi, T. axei and Haemonchus adult and larval stages by 99.13%, compared with untreated controls. There was no relationship between faecal egg counts and total worm counts. Gross pathology showed that strategic deworming on pasture reduced the mean abomasal lesion score at slaughter. An interaction between pasture treatment and feedlot treatment showed that feedlot deworming of pasture control steers reduced mean histopathology score, while feedlot deworming of steers strategically dewormed on pasture had no impact. Distribution of histopathology scores showed that strategic deworming on pasture resulted in more steers without histopathological changes to the abomasal mucosa and fewer steers with higher histopathology scores.
Case report
Authors: Schukken Ynte H. , Gonzalez Ruben N. , Wilson David J. , Garrison Linda , Welcome Frank , Bennett Gary , Schulte Hal , Julius Fred , Saltman Roger
Published: March 2023

Extralabel treatment of mastitis in dairy cows may be of questionable efficacy and legality. This study examines the extralabel use of an antibiotic mixture compounded by a veterinary clinic to treat cows for mastitis on 3 farms. The mixture contained penicillin, spectinomycin and dexamethasone. The literature and regulations regarding use of each of these drugs for treatment of mastitis are discussed. The requirements established by the Animal Medicinal Drug Use Clarification Act (AMDUCA) were not met. The objective of this report is to increase awareness of risks involved in extralabel use of antibiotics. Adulteration of the compounded product, and potential for drug residues in foods from animal origin, are of particular concern.
Choosing the right cutoff level of milk progesterone to determine pregnancy status of dairy cows on day 21 post-breeding
Authors: Carriere Paul D. , DesCoteaux Luc , Bigras-Poulin Michel
Published: March 2023

A field study was conducted between February and November 1995 in 3 Holstein dairy herds (193 inseminations) to determine the overall accuracy and usefulness of the skim milk progesterone pregnancy test on day 21 post-breeding, and to examine the effects of using different cutoff values and conception rates on predictive values of this pregnancy test. Results of the milk progesterone test were compared with pregnancy diagnosis after 25 days post-breeding using transrectal ultrasonography and palpation as a standard. The conception rate of the study population based on transrectal palpation was 42%. The relative sensitivity, specificity, and positive and negative predictive values of the milk progesterone test at a cutoff level of 1 ng/ml were 90, 67, 66 and 90%, respectively. It is suggested that in a herd population with a conception rate of 42%, the milk progesterone test is not a good predictor of pregnancy because the proportion of false positive results was high at 19% (37 of 193). The capacity of the test to detect open cows is acceptable with an overall proportion of false negative tests of 4% (8 of 193). Because 8 of 83 cows tested negative were subsequently diagnosed pregnant by transrectal examinations, this milk progesterone test would be expected to result in a 10% probability of misdiagnosing pregnant cows as non-pregnant. If this test was applied in the field, the 1 ng/ml cutoff value would be expected to result in optimum probabilities (>90%) in predicting non-pregnancy in dairy herds with a conception rate of <50%. Herds with a conception rate >50% would not be expected to benefit as much from the test since the predictive value of a negative test is <90%. Finally, considering that a false negative diagnosis is more costly than a false positive, the optimum cutoff value was also calculated at a 3:1 ratio in favour of finding fewer false negatives. In this case, the optimum cutoff value for the herd with a 42% conception rate was 1.2 ng/ml. This study shows that the usefulness of the progesterone test relies on assessing the right cutoff level for the milk progesterone pregnancy test which relies not only on the measurement itself, but also on the expected conception rate and the ratio between false negative and false positive test results.
Ovsynch Breeding Program for Dairy Cows
Authors: LeBlanc Stephen
Published: March 2023

Heat detection is the single biggest impediment to improved reproductive performance in many dairy herds. Recently, a program for synchronization of ovulation ("Ovsynch") has been developed, which allows for breeding by scheduled artificial insemination. This paper reviews the literature on synchronization of ovulation in lactating dairy cows, and evaluates the economic impact of using the Ovsynch program. Ovsynch offers a method to reliably achieve timely pregnancies without heat detection initially. It increases the rate of insemination and allows control over time to first breeding, while having minimal impact on conception rate. In herds with poor or average heat detection, Ovsynch is economically beneficial as a first line reproductive management program for the herd.
Culling and Laminitis
Authors: Nelson Arden J. , Cattell Marguerita B.
Published: March 2023

Four New York dairy herds, ranging in size from 518 to 2007 cows, were studied. The overall culling rate was 27.6% and ranged from 15.6% to 42.9%. Cows with a history of laminitis lesions were culled during the current lactation at a rate 1. 77 times higher than cows with no laminitis lesions. A history of laminitis in the current lactation significantly increased the likelihood of culling due to foot and leg problems, reproduction, mastitis, low production and other reasons. Overall, laminitis was associated with 9.8% of culling in the entire herd and 43.5% of culling among cows with a history of laminitis.
Case report
Authors: Wells N. H. , Hallford D. M. , Hernandez J. A. , Bollinger J. L. , Peterson M. K. , McElyea U.
Published: March 2023

Thirty-one Debouillet ewe lambs were exposed to elevated dietary copper (Cu) after being fed pelleted alfalfa from two separate feed mills which contained 33 and 45 ppm Cu. After consuming about 5.5 lb/day of this diet for approximately 50 days, signs of Cu poisoning became apparent (hemoglobinemia, hemoglobinuria). Cu toxicity was confirmed by a liver Cu concentration of 439 ± 36 (mean± SE) ppm in five dead animals. During the course of Cu exposure, eight of 31 ewe lambs died. Serum was collected from 10 ewe lambs showing extreme signs of Cu poisoning. Total, direct, and indirect bilirubin, and creatine kinase ( CK) were elevated in ewes consuming Cu. Ten extremely affected ewe lambs that had stopped consuming any feed received gelatin capsules (gavage) containing about 2 oz of a livestock salt/gypsum (76% calcium sulfate) mixture (2:1, weight basis) daily for 10 days. After 10 days of calcium sulfate treatment, serum bilirubin and CK were at or near normal concentrations and neither hemoglobinemia nor hemglobinuria were observed. Calcium sulfate administered in gelatin capsules appears to aid in the treatment of acute Cu toxicosis in sheep.
Seroprevalence of Neospora caninum Infection in 25 Ontario Dairy Herds and its Association with Periparturient Health and Production
Authors: Duffield T. F. , Peregrine A. S. , McEwen B. J. , Hietala S. K. , Bagg R.
Published: March 2023

Serum samples were collected in 1995/1996 from 7 58 animals on 25 Ontario Holstein dairy farms at three weeks prior to expected calving. The frozen sera were subsequently analyzed for anti-Neospora caninum antibodies. Herd seroprevalence was 60% and 73% using two different cut-off values for defining infection. Using the lower cut-off, within-herd seroprevalence ranged from Oto 38% with a mean of 9.0% in seropositive herds. Seropositivity was associated with a 3.8-fold increased risk ofretained placenta. No significant impact of infection on milk production was detected for the first three Dairy Herd Improvement test-day evaluations of each cow's lactation.
Case report
Authors: Niles Gene A. , Edwards W. C. , Morgan Sandra
Published: March 2023

Blister beetle poisoning (cantharidiasis) of horses has been well documented. Primary exposure to blister beetles is through consumption of contaminated lucerne hay. Confirmed cases of bovine cantharidiasis due to natural exposure have not previously been documented in veterinary literature. This report describes four cases of blister beetle poisoning in three dairy herds and one beef herd in New Mexico and Oklahoma, USA, that were reported between 1995 and 1999. Cows in two large dairy herds consumed blister beetles in a total mixed ration containing green chop lucerne. The most significant clinical signs were mass refusal to eat the freshly cut green chop lucerne, although the cows appeared hungry, and the corresponding dramatic decrease in milk production. Cows in a smaller dairy herd and a beef herd consumed large round bales of lucerne hay containing blister beetles. In contrast to cows exposed to the beetles in green chop, feed refusal in these cases was limited to individual cows. Other clinical signs included salivation, bruxism, frequent urination, diarrhoea, reluctance to move, abdominal pain, ataxia and recumbency. Postmortem examination did not reveal significant gross or microscopic lesions. Cantharidin was detected by gas chromatography-mass spectrometry analysis of either urine or feed samples. In addition, blister beetles were found in the lucerne green chop or hay.
Conception rate of lactating dairy cows using ovsynch after presynchronization with prostaglandin F2α (PGF2α) or Gonadotropin Releasing Hormone (GnRH)
Authors: Bartolome J.A. , Sheerin P. , Luznar S. , Melendez P. , Kelbert D. , Risco C.A. , Thatcher W.W. , Archbald L.F.
Published: March 2023

This study compared the pregnancy rate in cows inseminated after two different pre-synchronization protocols based on clinical features of the genital tract and treatment with either PGF2α or GnRH. A total of 340 reproductively normal lactating dairy cows was divided in two groups. Cows in Group 1 (n=216) had a corpus luteum when palpated per rectum on day 0. These cows were administered 25 mg of PGF2α on day 0, 100υg ofGnRH on day 14, 25 mg of PGF2α on day 21, 100 υg of GnRH on day 23, and time-inseminated 16-h later. Cows detected in estrus from day Oto day 14 were inseminated 10 to 12-h after signs of estrus.

Cows in Group 2 (n=124) either had a large ovarian follicle and uterine tone, or a corpus hemorragicum whenpalpated per rectum on day 0. These cows received 100 υg of GnRH on day 0, 100 υg of GnRH on day 8, 25 mg of PGF2α on day 15, 100 υg of GnRH on day 17, and time-inseminated 16-h later. Cows detected in estrus before the end of the treatment protocol were inseminated 10 to 12-h after signs of estrus and removed from the study. Data collected were pregnancy rate for cows time-inseminated in Group 1, cows inseminated at detected estrus in Group 1, and cows time-inseminated in Group 2. Pregnancy rates were compared using logistic regression adjusted for number of previous services, parity, season and days in milk. There was no difference (p=0.83) in pregnancy rate between cows time-inseminated in Group 1 (35.9%) and Group 2 (32.8%). In Group 1, there was no difference (p=0.21) in pregnancy rate between cows time-inseminated (35.9%) and cows inseminated at detected estrus within 14-d after treatment with PGF2α (43.5%). Results of this study suggest that cows in different stages of the estrous cycle, as determined by rectal palpation of the genital tract, had similar pregnancy rates when they were selectively pre-synchronized with either PGF2α or GnRH.
Behavior of cattle towards devices to detect food-safety pathogens in feedlot pens
Authors: Irwin Katherine E. , Smith David R. , Gray Jeff T. , Klopfenstein Terry J.
Published: March 2023

Our objective was to optimize a protocol using rope devices designed to detect Escherichia coli O157:H7 in feedlot pens by (1) determining if the number of devices influenced the percent of cattle sampled, (2) describing when the cattle contacted the devices, and (3) determining if the time of removal or number of devices influenced the recovery or E. coli O157:H7. Overall, 2948 cattle were observed in 24 commercial feedlot pens, eight pens each in the autumn, winter and summer. Three or seven devices per pen were placed near the water tank and over the feed bunk approximately one hour prior to sunset. Cattle were observed for a 2-hour period to measure (1) the duration of time until they made contact with the devices, and (2) the type of contact they had with the devices. One tail from each of the devices was collected at the end of the 2-hour observation period (ending approximately one hour after sundown) and the other tail was collected the next morning to test for the presence of E. coli O157:H7. Recovery of E. coli O157:H7 was not significantly different using three or seven devices (p>0.10), or if devices were left available overnight (p>0.10). The rate of first contacts did not differ between pens with three or seven devices in any of the 30-minute periods of observation (p>0.50). However, regardless of the number of devices in the pen, the first contact rate was highest in the first 30 minutes and decreased significantly with time (p<0.001). Over the 2-hour observation period, a greater percentage of cattle in pens with seven devices had physical (p<0.01), brief oral (p<0.02), or prolonged oral contact (p<0.01) than cattle in pens with three devices. Therefore, to maximize the number of cattle sampled per pen, the number of devices and length of time the devices are available were important factors of the sampling strategy.
Case report
Authors: Kirk John H. , Sischo William M.
Published: March 2023

A California dairyman milking 1,969 cows reported excessive cases of clinical mastitis, and questioned whether teat-end lesions were associated with the problem. Using a system of teat-end lesion classification, the entire milking herd was observed for lesions during January 2002. Overall, 9.9% of the herd had some type of lesion, including warts and severe hyperkeratosis; 67% of lesions were severe teat-end hyperkeratosis. Cows with teat lesions were three times more at risk of clinical mastitis compared to cows without teat lesions. Because of physical limitations of the milking equipment and the owner’s reluctance to modify the milking routine, no management changes were made.
High production and health
Authors: Fetrow John , Eicker Steve
Published: March 2023

This paper has looked through 3 different aspects at the question of whether increased production puts a cow at greater risk of disease: (a) changes in rates of disease across the decades as production increases, (b) cohort studies, and (3) the impact of increased production from recombinant bovine somatotropin (rBST) use. While there is considerable belief that high producing cows are more likely to suffer various negative events (disease, culling, etc.) than low producers, there is very little data to support that belief for most conditions. With the possible exceptions of clinical mastitis and milk fever, most studies find no causal connection between high production and the risk of negative events in a cow's life.
Efficacy of metaphylactic tilmicosin for controlling bovine respiratory disease in high-risk northern feeder calves
Authors: Guthrie Carl A. , Rogers Karen C. , Christmas Rod A. , Vogel Gary J. , Laudert Scott B. , Mechor Gerald D.
Published: March 2023

The objectives of this study were to: (1) evaluate the effect of metaphylactic tilmicosin on the health and performance of high-risk northern calves, and (2) determine the efficacy of tilmicosin for treatment of bovine respiratory disease (BRD) following its use in an arrival metaphylaxis programme. 400 crossbred steer calves weighing an average of 273 kg each were purchased at livestock auctions in South Dakota and Montana, and shipped to a commercial research feedlot in northern Colorado. At processing, calves were randomly assigned to one of two treatment groups: (1) non-medicated controls or (2) metaphylaxis with tilmicosin. Cattle assigned to the metaphylaxis group were administered tilmicosin once at label dose. Control cattle received no antibiotic at processing. Metaphylactic use of tilmicosin at processing reduced BRD morbidity compared to controls (25.5 vs, 56.5%, P<0.01). Average number of days to first pull were greater in the metaphylaxis group (13.9 vs. 9.6 d, P<0.01). BRD mortality and chronic rates did not differ between treatments. When calculated on a "deads out" basis, calves receiving tilmicosin at processing gained more weight during the first 28 d (1.66 vs. 1.41 kg/d, P<0.01), and 102 d on feed (DOF) (1.75 vs. 1.67 kg/d, P<0.01) compared with control calves. At harvest (191 DOF), daily gain tended to be greater (1.55 vs. 1.52 kg/d, P=0.10) for calves in the metaphylactic tilmicosin treatment group. There were no differences in feed intake or feed conversion between groups. Hot carcass weight tended to be greater for calves in the metaphylactic treatment group (359.8 vs. 353.5 kg, P=0.06). Other carcass traits did not differ. When tilmicosin was used as first treatment for calves with BRD, response rates were identical for both treatment groups (86%). No differences were observed between treatment failure (6.5 vs. 4.6%, P=0.68), first relapse (7.5 vs. 9.4%, P=0.71), second relapse (4.4 vs. 2.7%, P=0.72) or new episode (11.9 vs. 10.8%, P=0.85) rates for calves in the metaphylaxis and control groups, respectively. In this study, metaphylactic treatment with tilmicosin at processing decreased morbidity, and increased days to first treatment for those calves that subsequently required BRD therapy. Efficacy of tilmicosin as the first line therapy for BRD following its use in an on-arrival metaphylaxis programme was not compromised based on the results of this study.
Johne's disease
Authors: Keller Linda L. , Harrell C. Dix , Loerzel Suzan M. , Rae D. Owen
Published: March 2023

The objective of this study was to estimate the prevalence of M. avium subsp. paratuberculosis infection among beef and dairy cattle in Florida, USA. This was a retrospective seroprevalence study on serum samples from 32?011 cattle originating from 75 herds. Selection was limited to whole herds being tested for diagnostic purposes by owners considering participation in the voluntary Johne's Control Programme or the voluntary Florida Johne's Disease Herd Status Programme. Data were obtained from the Florida State Veterinary Diagnostic Laboratory and USDA-APHIS statewide submission of specimens for Johne's testing from 1999 to 2001. Specimens were evaluated using a commercial IDEXX ELISA kit with a published sensitivity and specificity of 50 and 99%, respectively. Overall prevalence in the sample population was 6.5%; prevalence in beef and dairy cattle was 7.4 and 6.3%, respectively. 83% of herds included in the study had one or more positive cows in the herd. Larger herds (>100 head) had statistically higher herd prevalence than herds with less than 100 cattle. The true prevalence estimate was calculated to be 11.2%. Although within-herd prevalence was lower than previously reported in Florida, seroprevalence appears to be widely distributed and pervasive among Florida cattle. Our findings suggest there could be 168?000 or more cattle in Florida infected with the organism. There is a need for increased awareness of the disease and implementation of control methods appropriate for each individual herd.
Case report
Authors: Wiedner Ellen B. , Horstman Lawrence A. , Hooser Stephen B. , Levy Michel
Published: March 2023

Two crossbred cattle were presented to a veterinary teaching hospital in December 2001 with muscarinic, nicotinic and central nervous system signs consistent with severe organophosphorus (OP) insecticide toxicity. Despite treatment, neither animal survived. Over the course of 72 hours, 34 cattle died acutely. A subsequent veterinarian-led visit to the farm identified a rusted, leaking corn planter containing a gray crumbling material, situated near where the cattle were fed. This substance was later identified as fonofos, an agricultural insecticide and an OP that was voluntarily removed from the marketplace by the manufacturer in 1998.
Monitoring return to cyclicity following removal of a granulosa cell tumor associated with precocious lactation in an 11-month-old Holstein heifer
Authors: Palmer Colin W. , Clark Edward G. , Carruthers Terry D.
Published: March 2023

An 11-month-old Holstein heifer was presented to the Western College of Veterinary Medicine for evaluation of precocious lactation associated with a palpably enlarged right ovary. Ultrasound examination of the ovaries revealed a 6 inch (15 cm) diameter right ovary with a multilobulated appearance, and a small left ovary measuring 0.6 inches (1.6 cm) long by 0.3 inches (0.8 cm) wide. The mammary secretion was consistent with milk: fat-3.07%, protein-4.78%, and lactose-1.07% with a somatic cell count of 4.8?106/mL. Prior to removal of the right ovary by right flank laparotomy, serum hormone levels were measured: testosterone (0.01 ng/mL), estradiol-17? (9.1 pg/mL), progesterone (0.2 ng/mL), prolactin (5.8 ng/mL), luteinizing hormone (0.14 ng/mL) and follicle stimulating hormone (0.32 ng/mL). Gross examination revealed that the right ovary weighed 7.34 oz (208 g) and was composed of numerous cysts (0.2-1.6 inches [0.5-4 cm] in diameter) containing fluid or blood. Microscopically, foci of cells of a follicular or luteal nature were noted. The definitive diagnosis was a right ovarian granulosa cell tumor, and milk secretion declined rapidly following tumor removal. The left ovary was monitored ultrasonographically at weekly intervals to determine onset of cyclicity. Follicular activity resumed between three and four weeks post-surgery, followed by detection of a corpus luteum at day 32. The heifer became pregnant five months post-surgery, and has since delivered a live calf. This case represents only the second reported case of precocious lactation associated with a granulosa cell tumor, and suggests that cyclicity is likely to return to the contralateral ovary less than a month after tumor removal.
Imaging study of myringotomy in dairy calves
Authors: Villarroel Aurora , Heller Meera C. , Lane V. Michael
Published: March 2023

Otitis media is common in dairy calves. Antibiotic treatment alone does not always result in complete resolution. Based on human paediatric medicine experience, where myringotomy tubes are commonly placed to drain purulent accumulations from the ear, it has been suggested that a myringotomy can be performed in calves. We investigated whether performing a myringotomy using a straight rigid instrument (knitting needle) is anatomically feasible in calves. Two imaging techniques and direct visualization were used to observe the trajectory of the needle and its immediate effects on the tympanic membrane. Our study shows there is no anatomic impediment to performing a myringotomy in calves with a straight rigid instrument.
Case report
Authors: Thomas Mark J.
Published: March 2023

Milk fat depression (MFD) is a common nutritional disorder on commercial dairy farms. Subacute rumen acidosis (SARA) secondary to inadequate effective fiber is traditionally one of the first areas to investigate when consulting with these herds. A less frequently recognized cause of MFD is the presence of unsaturated oils in the ration, which can have an indirect effect on milk fat synthesis. One of the predominant fatty acids produced in the rumen is conjugated linoleic acid (CLA). Under certain altered rumen fermentation processes, the biochemical pathway produces an increased amount of the trans vs. the cis-isomer of CLA. These trans-isomers of CLA are potent inhibitors of milk fat synthesis. This case report will detail the process by which there is diet-induced milk fat depression despite adequate forage intake and apparent normal rumen health.
Feed intake response of feedlot cattle following single-dose treatment of ceftiofur crystalline free acid sterile suspension or florfenicol
Authors: Boyd M. E. , Bowers A. M. , Engelken T. J. , Bryson W. Lawrence , Moseley William M.
Published: March 2023

Healthy feedlot cattle were injected with either ceftiofur crystalline free acid (CCFA-SS) or florfenicol at the label dosage in a replicated, three treatment, 21-day study. Daily dry matter intake (DDMI), average daily gain (ADG) and feed efficiency (F:G) were compared between untreated controls and calves injected with CCFA-SS or florfenicol. The study was conducted at Mississippi State University (MSU) and the Pfizer Animal Health Research Farm (PAH). At MSU, 48 steers (630 lb; 286 kg) were individually fed in four pens with 12 Calan gates in each pen, while 192 steers and heifers (847 lb; 385 kg) were group fed in 24 pens, each holding eight head at PAH. Steers and heifers were fed separately during the trial. Treatments were randomly assigned to animals at MSU and to pens at PAH. DDMI for cattle treated with CCFA-SS was similar to controls on all days at both locations. Dry matter intake for calves treated with florfenicol was lower (P<0.05) than controls on days 2, 4, 5, 8 and 9 at MSU, and days 1-13 at PAH. ADG of calves treated with CCFA-SS at MSU was significantly greater than controls (4.37 and 3.45 lb; 1.99 and 1.57 kg, respectively) during the 21-day study, while ADG (2.04 lb; 0.93 kg) of calves treated with florfenicol was lower (P<0.01). There were no differences in ADG between treatment groups at the PAH study location. Feed:gain (feed efficiency) of calves treated with CCFA-SS was similar to control calves at both study locations (P=0.77). Feed:gain of cattle treated with florfenicol was similar (P=0.50) to controls at PAH, but was higher (less efficient) than control cattle at MSU (F:G 8.57 vs 3.71, P<0.01).
Ocular dermoids in cattle
Authors: Castro Jose R. , Hendrix Diane V. H. , Van Amstel Sarel R.
Published: March 2023

A 2-week-old calf in the USA was presented because of severe ocular irritation; examination revealed a large conjunctival dermoid. A conjunctivectomy was curative, as evidenced by no recurrence with a 4-month follow up. A review was compiled from the literature and the Veterinary Medical Database. Dermoids have been reported in 22 breeds of cattle, with the Hereford being overrepresented. Average age at presentation is 6.1 months. Calves usually show signs of severe ocular irritation, which is caused by hair on the surface of the dermoid. Dermoids may occur on the cornea, limbus or conjunctiva. Surgical excision via keratectomy or conjunctivectomy after sedation with xylazine and local anaesthesia is curative in most cases.
Field evaluation of prophylactic and therapeutic effects of a vaccine against (papillomatous) digital dermatitis in dairy cattle on two California dairies
Authors: Ertze Ricardo A. , Read Deryck H. , Hird David W. , Berry Steven L.
Published: March 2023

The objectives of this study were to determine the prophylactic and therapeutic effects of a Treponema bacterin against papillomatous digital dermatitis ((P)DD) in lactating dairy cows from 2 California dairies and to compare the serological response to the Treponema bacterin between vaccinate and placebo groups of cows. A total of 1160 Holstein-Friesian cows were used in this study. The cows were grouped according to treatment (vaccinated or placebo) and visible (P)DD lesion status prior to treatment. 120 cows with no visible lesions prior to treatment were bled for serological evaluation. Monthly visual and serological evaluations were performed before and after the treatment for 6 months. Comparison of monthly proportion of cows between groups of vaccinates and placebos showed insignificant prophylactic or therapeutic effects due to the Treponema bacterin. Results were also insignificant when monthly proportions of cows were stratified by lactation groups or for only those cows present at every monthly observation and stratified by lactation groups. ELISA titres of the 120 cows bled prior to treatment showed that 43% of the cows had positive titres, indicating prior exposure to Treponema spp. Comparison between monthly proportions of vaccinates and placebo cows that had no visible (P)DD lesions, and which had negative serological titres to (P)DD-associated Treponema spp. antigens prior to treatment, showed that a significantly higher proportion of vaccinates developed a positive serological state during the 1st, 2nd and 3rd months after treatment.
Effect of an immunostimulant administered at or near weaning on weight gain and health of beef calves
Authors: Hoar B. R. , Myers D. M.
Published: March 2023

Weaning is generally regarded as a very stressful event in the life of calves, and is often associated with an increase in morbidity and reduced weight gain. Various management strategies are employed in an effort to reduce the impact of weaning on calf health and productivity. This study examined the effects of a nonspecific immune stimulant, mycobacterial cell wall (MCW), administered at or near weaning on the subsequent morbidity and growth of beef calves and assess the effects of a single dose of MCW on white blood cell parameters when given on the day of weaning. Heifer calves (n=137) were treated with either MCW or saline two weeks prior to weaning, while steer calves (n=60) were given either MCW or saline on the day of weaning and were monitored for 120 days. Results revealed that there were no observed differences between treatment groups in either weight gain or number of disease events. Under the conditions of this trial, administration of MCW at or near weaning did not have a significant effect on calf health or weight gain.
Botulism in cattle
Authors: Moeller Robert B. , Puschner Birgit
Published: March 2023

Botulinum toxins are considered the most lethal toxic substances known to man. Eight botulinum toxins are produced by different strains of Clostridium botulinum, C. baratii and C. butyricum. Cattle are primarily affected by botulinum toxins B, C and D. Although these botulinum toxins can be found worldwide, certain botulinum toxins have predominance in certain geographical regions. Poisoned cattle often show muscle weakness, constipation, colic, ataxia, muscle fasciculation, decreased tongue tone and dirty noses. Currently no treatments other than supportive care are available for affected cattle.
Hairy vetch (Vicia villosa) toxicosis in a purebred Angus herd
Authors: Washburn Kevin , Norman Tracy , Osterstock Jason , Respondek Travis
Published: March 2023

Four mature, purebred Angus cattle from a herd of 460 are presented at the Texas Veterinary Medical Center at Texas A and M University, Texas, USA with a history of weight loss and alopecia that began one to seven days prior to examination. Five unexplained deaths of other members of this group, within the same pasture, had occurred on the ranch during the previous two weeks. Clinical findings common to all four animals were skin lesions that ranged from mild alopecia with moderate hyperkeratosis, severe folding and thickening of the skin with excoriation and edema. Lesions were distributed bilaterally on the face, neck, topline, perineum, distal limbs, udder and thorax. Increased salivation, clear ocular discharge and lymphadenopathy were also observed in all four animals. Skin biopsy, histopathological examination, serum biochemical findings and hematology results were consistent with hairy vetch (Vicia villosa) poisoning. Cattle were removed from this pasture and the other affected animals were isolated for observation and supplemental feeding.
Salmonella and the market dairy cow
Authors: Troutt H. Fred , Galland John R. , Hyatt Doreen , Rossiter Christine , Lein Donald R. , Brewer Robert R. , Wilson Dennis
Published: March 2023

Floors of trucks or trailers were sampled for Salmonella before culled dairy cows were loaded from cooperating farms and auction markets in New York (East) and California (West) prior to transport to slaughter establishments. Sampling occurred during two periods, winter and summer. These vehicles were sampled again after cattle were unloaded at slaughter establishments. Four of six vehicles picking up cattle from dairy farms were positive for Salmonella spp. before cattle were loaded at East locations during winter, while five of seven were positive during the summer. One of five vehicles picking up cattle from auction markets was positive for Salmonella spp. at an East location during winter, while all four sampled during the summer period were positive. During winter at the West location all trucks or trailers were positive for Salmonella . During the summer sampling, nine of 13 vehicles that arrived at dairy farms and four of six that arrived at auction markets to pick up cattle were positive for Salmonella before cattle were loaded. Biosecurity procedures need to address the risk of Salmonella contamination from cattle transport.
AABP Conference (2007): List of Exhibitors
Authors: Bovine Practitioners American Association of
Published: March 2023

Description of the 2007 American Association of Bovine Practitioners Conference.
Case study
Authors: LeBlanc Stephen J.
Published: March 2023

The objective of this field study was to measure the effect of implementing a simple systematic reproduction management program in dairy herds with reproductive performance near or below typical in the industry. Thirty-nine herds across Canada that had annual herd 21-day pregnancy rates (PR) between 8 and 15%, and did not have a systematic reproduction program, were enrolled in a program that consisted of: enrollment of cows that were not inseminated by 70 days-in-milk into a timed insemination program (Ovsynch); enrollment of cows diagnosed not pregnant on Ovsynch; and a change to biweekly veterinary visits for reproductive management. Annual herd PR was compared one year after implementation of the program. On average, the systematic management program was associated with a mean increase in PR of 3.6 percentage points (95% confidence interval, 2.5 to 4. 7; P<0.0001), accounting for initial insemination and conception rates, herd size and method of pregnancy diagnosis. Assuming a milk price of $23/cwt to reflect Canadian milk price net of purchase of quota, economic analyses indicated that herds that increased PR by at least two points were estimated to have an annual net profit improvement between $20 and $250 CDN per cow, depending on the initial PR and the magnitude of the increase in PR. Overall, 72 to 77% of herds that implemented the program were estimated to have a net economic benefit.
Case report
Authors: Wilson David J. , Trujillo Jessie D. , Skirpstunas Ramona T. , Cavender Kimberly B.
Published: March 2023

Two apparently healthy cows on a commercial dairy farm died within 48 hours following intramammary (IMM) infusion of dry-cow treatment at the end of lactation. Teat dip containing sodium chlorite lactic acid had been stored for two years on the farm and was used only to dip teats following IMM infusion with dry-cow treatment. The sodium chlorite lactic acid teat dip, stored in the original container that was visibly soiled externally, was culture-positive for Serratia liquefaciens. This is the first reported isolation of a contaminant from sodium chlorite lactic acid teat dip. Soiled containers of teat dip or those opened and stored for long periods of time should be cultured to monitor contamination of bacteria or preferably discarded.
Effect of bedding conditioners on bacteria counts and pH in shavings, digested manure solids and recycled sand bedding
Authors: Bey R. , Godden S. , Kuechle B.
Published: March 2023

A controlled trial was conducted in 16 commercial dairy herds to describe the effect of an alkalinizing (A) and an acidifying (B) bedding conditioner on bedding pH and bacterial counts when applied twice per week to stalls containing shavings (SH), digested manure solids (DS) or recycled sand (RS) bedding materials. Bedding pH and bacterial counts were measured in samples collected one day, and again in three to four days, after new conditioner was applied to the stalls. Conditioners A and B had an alkalinizing and acidifying effect, respectively, on bedding pH. Although conditioner A reduced coliform bacterial counts by between 0.7 and 1.6 logs in RS and DS bedding for one day and it had no effect on Klebsiella spp. or Streptococcus spp. bacterial counts in these bedding materials. Activity against coliform bacterial counts did not persist for three to four days. Conditioner A reduced bacterial counts in SH by between 0.3 to 1.3 logs for at least one day, but had no persistent activity for three to four days when stalls were rebedded. Conditioner B did not reduce bacterial counts in either DS or RS bedding, and actually increased Klebsiella spp. bacterial counts in DS. However, conditioner B reduced bacterial counts in SH for one day (0.4 to 1.8 log reduction, depending on the bacteria group), with antibacterial activity persisting for three to four days post-application (0.4 to 0.6 log reduction), even though stalls had been rebedded in the interval between conditioner application and collection of the day 3 to 4 bedding samples. For all bedding materials studied, bacterial counts were significantly lower in stalls for which fresh bedding had been added within the previous 24-48 hours. The magnitude of reduction in bacterial counts associated with having recently bedded stalls (approximately 1.6, 0.6, and 1.6 log reduction in coliform, Klebsiella spp., and Streptococcus spp. bacteria, respectively) was, on average, greater than the magnitude of reduction in bacterial counts attributed to the bedding conditioner treatments being studied. These findings suggest that the alkalinizing conditioner A will not be useful on commercial dairies, regardless of bedding type in use, if applied only twice per week in accordance with manufacturer recommendations. The acidifying conditioner B will not be useful on commercial dairies using DS or RS bedding, but may be useful to reduce bacterial counts in SH bedding. Finally, findings suggest that producers can significantly reduce bacterial exposure to teat ends simply by applying fresh bedding to stalls on a more frequent basis.
Comparison of two vaccines to reduce liver abscesses in natural-fed beef cattle
Authors: Fox J. T. , Thomson D. U. , Lindberg N. N. , Barling K.
Published: March 2023

A blinded interventional clinical trial was conducted to evaluate the efficacy of two liver abscess vaccines in natural-fed beef cattle. Feedlot cattle (n=1,307 head, initial body weight=613±71 lb; or 279±32 kg) were randomly assigned to one of three vaccine treatments: no vaccine (control); vaccination with a Fusobacterium necrophorum bacterin (Fusogard?, Novartis Animal Health US, Inc, Greensboro, NC); or vaccination with an Arcanobacterium pyogenes-Fusobacterium necrophorum toxoid (CenturionTM, Intervet/Schering-Plough Animal Health, DeSoto, KS). Cattle were fed a finishing diet consisting of 73% steam-flaked corn arid 13% roughage (as-fed basis). At harvest, livers were scored using the Elanco Liver Scoring System. Incidence of liver abscesses (56%) and severe liver abscesses (39%) was relatively high in this study. Vaccine treatment did not affect incidence of liver abscesses or severe liver abscesses, nor did it affect liver abscess score. Initial body weight, 60-day body weight, 60-day average daily gain (ADG), total days-on-feed (DOF), hot carcass weight, yield grade, and quality grade were not different among vaccine treatments. Cattle with abscessed livers at harvest tended to have lower 60-day ADG than those without abscesses. Presence of liver abscesses increased (P=0.02) total DOF, but only by two days. Presence of severe liver abscesses was associated with reduced (P<0.01) hot carcass weight, and more cattle that graded USDA Select rather than USDA Choice (P=0.01).
Evaluation of efficacy and benefit of ivermectin with clorsulon and long-acting moxidectin in replacement beef heifers
Authors: Powell J. G. , Yazwinski T. A. , Tucker C. A. , Johnson Z. B. , Brown A. H. , Reynolds J. L. , Clymer B. C.
Published: March 2023

A two-year study was conducted to assess the effects of ivermectin (with clorsulon) and long-acting moxidectin on the development of replacement beef heifers carrying naturally occurring parasite infections. Replacement beef heifers (n=105) were obtained at weaning and co-grazed on permanent pastures throughout the 686-day study. Study heifers were treated with ivermectin and clorsulon (IVCL), long-acting moxidectin (LMXD), or left untreated (CON). Treatments were administered on days 0 and 149. Compared to CON, heifer body weights were greater (P<0.05) for LMXD and IVCL-treated animals on days 175, 238, 287, 369, and 433. Average daily gains were greater (P<0.01) for LMXD and IVCL-treated heifers compared to CON heifers from days 0 to 433. Fecal strongyle egg counts were lower (P<0.01) for LMXD-treated heifers on days 14, 64, 149, 169, 238, and 287 compared to the IVCL and CON groups. Fecal egg counts for the IVCL group were lower (P<0.01) than those in the CON group on days 14 and 169, the samplings subsequent to animal treatments. Weight gain of calves born to the study heifers was greatest for calves born to LMXD-treated heifers, intermediate for calves born to IVCL-treated heifers, and lowest for calves born to CON heifers.
Case report
Authors: Remsburg Darren W. , Munson Robert J. , Elliot R. Dean , Baker Linda D. , Ferguson James D. , Galligan David T. , Wu Zhiguo , Ramberg Charles F. , Dou Zhengxia
Published: March 2023

The Field Investigation group (FI) at the University of Pennsylvania School of Veterinary Medicine was contacted for consulting services for two farms with economic and nutritional management concerns. Farm A was a 732-cow dairy referred by one of the authors (RDE) for concerns over ration cost and transition cow health. Farm B was a 98-cow dairy that contacted FI because of financial difficulties, specifically the high cost of the diets. In both cases, FI veterinarians evaluated and reformulated diets that resulted in positive economic, production, and environmental consequences. Farm A increased test-day milk, fat, and protein yield by 7.2, 0.03, and 0.07 lb (3.3, 0.014, and 0.032 kg)/cow/day after the diet reformulation. The ration also saved $0.45/cow/day while decreasing nitrogen and phosphorus excretion by 1.44 oz (40.9 g) and 0.11 oz (3.12 g)/cow/day, respectively. Farm B increased test-day milk, fat, and protein yield by 1.2, 0.11, and 0.04 lb (0.54, 0.05, and 0.018 kg)/cow/day after FI intervention. Ration cost was reduced by $1.09/cow/day, nitrogen excretion was reduced by 0.3 oz (8.5 g)/cow/day and phosphorus excretion was not changed.