Billy I. Smith

Serum haptoglobin concentrations in dairy cattle with lameness due to claw disorders.

In cattle, elevated blood serum concentrations of haptoglobin, an acute phase protein, have been demonstrated in association with several diseases, but not with lameness. Serum haptoglobin was measured in 60 Holstein dairy cattle diagnosed with lameness due to four claw disorders, pododermatitis septica (PS; n=41), pododermatitis circumscripta (PC; n=8), interdigital necrobacillosis (IN; n=7), papillomatous digital dermatitis (PDD; n=4). Haptoglobin was measured on day 1 (0-3 days after lameness was observed but before treatment) and on days 3 and 5. A total of 10 healthy cows served as controls (haptoglobin values <1.0 mg/dL). Each of the claw disorders was associated with elevated haptoglobin on day 1 (PS, PC, IN and PDD: 65.9%, 37.5%, 71.4% and 25.0%, respectively). Trimming and antibiotic treatment led to a reduction in the number of PS and IN cows with increased haptoglobin concentrations, respectively (P<0.05), but trimming did not lead to any reduction in cows with PC. The study showed that lameness due to claw disorders can be associated with a systemic acute phase response and elevated serum haptoglobin in dairy cattle. Based on the course of haptoglobin, treatments seemed effective for all claw disorders except for PC.

Evaluation of Free-Stall Mattress Bedding Treatments to Reduce Mastitis Bacterial Growth

Bacterial counts were compared in free-stall mattresses and teat ends exposed to 5 treatments in a factorial study design on 1 dairy farm. Mattresses in five 30-cow groups were subjected to 1 of 5 bedding treatments every other day: 0.5 kg of hydrated limestone, 120 mL of commercial acidic conditioner, 1 kg of coal fly ash, 1 kg of kiln-dried wood shavings, and control (no bedding). Counts of coliforms, Klebsiella spp., Escherichia coli, and Streptococcus spp. were lowest on mattresses bedded with lime. Mattresses bedded with the commercial acidic conditioner had the next lowest counts for coliforms, Klebsiella spp., and Streptococcus spp. Wood shavings and the no-bedding control had the highest counts for coliform and Klebsiella spp. Compared with wood shavings or control, fly ash reduced the counts of coliforms, whereas for the other 3 bacterial groups, the reduction was not always significant. Streptococcus spp. counts were greatest in the control group and did not differ among the shavings and fly ash groups. Teat swab results indicated that hydrated lime was the only bedding treatment that significantly decreased the counts of both coliforms and Klebsiella spp. There were no differences in Streptococcus spp. numbers on the teats between any of the bedding treatments. Bacterial populations grew steadily on mattresses and were generally higher at 36 to 48 h than at 12 to 24 h, whereas bacterial populations on teats grew rapidly by 12 h and then remained constant. Hydrated lime was the only treatment that significantly reduced bacterial counts on both mattresses and teat ends, but it caused some skin irritation.

Diagnosis and treatment of four stallions, carriers of the contagious metritis organism—case report

Contagious Equine Metritis (CEM), a venereal disease of horses caused by the bacterium Taylorella equigenitalis, was first diagnosed in 1977 and subsequently spread to many nations [Proc 24th AM Assoc Equine Pract (1979) 287]. The disease was confirmed in the United States in 1978 [Proc Am Assoc Equine Pract (1983) 295]. Specific regulatory procedures for this disease have been established in the United States and 37 other countries. From 1999 through 2001, four of 120 imported European stallions tested positive for CEM at a quarantine facility in Darlington, MD, USA. Two stallions were identified by positive bacterial cultures for T. equigenitalis on arrival. The other two positive stallions were negative on initial bacterial cultures, but were identified as CEM carriers when test mares (that they had mated) were culture-positive for T. equigenitalis. Since T. equigenitalis, is a fastidious slow-growing coccobacillus, additional sets of samples taken over a interval might be required to ensure positive stallions are detected before mating test mares. Likewise, additional sets of samples taken over a long interval after treatment of a stallion for CEM might be required to ensure that positive stallions treated for CEM are detected before mating test mares. Aggressive systemic antibiotic therapy accompanied by routine topical therapy might be required to treat some CEM-positive stallions.

Pharmacokinetics of intravenously and orally administered meloxicam in sheep

OBJECTIVE To determine the pharmacokinetics of meloxicam after IV and PO administration to 6 healthy sheep. ANIMALS 6 healthy adult Dorset cross sheep (5 males and 1 female). PROCEDURES Meloxicam (0.5 mg/kg, IV, or 1.0 mg/kg, PO) was administered in a randomized crossover design with a 10-day washout period. Blood samples were collected at predetermined times over 96 hours. Serum drug concentrations were determined by high-pressure liquid chromatography with mass spectrometry. Computer software was used to estimate values of pharmacokinetic parameters through noncompartmental methods. RESULTS Following IV administration (n = 5), the geometric mean (range) elimination half-life was 14.0 hours (10.5 to 17.0 hours), volume of distribution was 0.204 L/kg (0.171 to 0.272 L/kg), and clearance was 0.17 mL/min/kg (0.12 to 0.27 mL/min/kg). Following oral administration (n = 6), maximum serum concentration was 1.72 μg/mL (1.45 to 1.93 μg/mL), time to maximum serum concentration was 19.0 hours (12.0 to 24.0 hours), clearance per bioavailability was 0.22 mL/min/kg (0.16 to 0.30 mL/min/kg), and terminal half-life was 15.4 hours (13.2 to 17.7 hours). Bioavailability of orally administered meloxicam was calculated as 72% (40% to 125%; n = 5). No adverse effects were evident following meloxicam administration via either route. CONCLUSIONS AND CLINICAL RELEVANCE Meloxicam administered PO at 1.0 mg/kg has good bioavailability with slow elimination kinetics in sheep. These data suggested that meloxicam may be clinically useful, provided the safety and analgesic efficacy of meloxicam as well as feed-related influences on its pharmacokinetics are established in ruminants.

Efficacy of major anthelmintics for reduction of fecal shedding of strongyle-type eggs in horses in the Mid-Atlantic region of the United States

In the last decade there have been numerous reports of anthelmintic resistant cyathostomins in many parts of the world. The objective of the present study was to evaluate the efficacy of the commercially available anthelmintics against cyathostomin egg shedding in the Mid-Atlantic region of the United States. A total of 989 horses from 67 different farms located in southeastern Pennsylvania, northern Delaware, and northeastern Maryland were treated with fenbendazole, oxibendazole, pyrantel pamoate, ivermectin, or moxidectin at their recommended dosages. Fecal egg count reduction testing was used to determine the efficacy of each anthelmintic on those horses with fecal egg counts of ≥ 200 eggs per gram on the day of treatment (272 horses). Decreased efficacy (reduction of strongyle-type fecal egg counts by less than 90%) was found for fenbendazole, oxibendazole, and pyrantel pamoate, with only 6%, 21% and 43% of horses showing reductions of greater than 90%, respectively. The macrocyclic lactones showed high efficacy in all horses sampled in this study. The decreased anthelmintic efficacy detected in this study adds further evidence for the existence of resistant cyathostomins throughout much of the eastern United States. Findings from this study can be used to create a more sustainable approach for parasite control programs.

Gastrointestinal spindle cell tumor of the rumen with metastasis to the liver in a goat

Many neoplasms have been reported in goats; however, neoplasia of the rumen is rarely reported. A 9-y-old castrated male pygmy goat was presented with a history of respiratory stertor, fever, and anorexia. A respiratory diagnostic work-up including skull and thorax radiographs and endoscopy revealed minor enlargement of the arytenoids but no other abnormal findings. After a month of little improvement on symptomatic treatment and worsening general health, the goat was euthanized. On autopsy, the forestomachs, liver, spleen, diaphragm, and the ventral and lateral aspects of the cranial third of the walls of the peritoneal cavity were adhered to one another by fibrinous and fibrous adhesions. Numerous firm, white, up to 2 cm diameter nodules were found throughout the liver. A large sessile mass extended from the rumen wall into the lumen. The rumen mass was a gastrointestinal stromal tumor with metastasis to the liver.

Anti-bovine herpesvirus and anti-bovine viral diarrhea virus antibody responses in pregnant Holstein dairy cattle following administration of a multivalent killed virus vaccine

OBJECTIVE To determine the effect of a commercially available multivalent killed virus vaccine on serum neutralizing (SN) and colostrum neutralizing (CN) antibodies against bovine herpesvirus (BHV) type 1 and bovine viral diarrhea virus (BVDV) types 1 and 2 in pregnant dairy cattle. ANIMALS 49 Holstein dairy cattle. PROCEDURES :25 cattle were vaccinated (IM injection) at least 60 days prior to calving (ie, at the end of the lactation period or according to the expected calving date for heifers) and again 5 weeks later. The remaining 24 cattle were not vaccinated (control group). Titers of SN antibodies were measured at the 5-week time point. Titers of SN and CN antibodies were measured at parturition. RESULTS 5 weeks after initial vaccination, titers of SN antibodies against BHV-1 and BVDV types 1 and 2 were 1:512, 1:128, and 1:2,048, respectively, in vaccinates and 1:64, 1:128, and 1:64, respectively, in unvaccinated controls. Equivalent SN antibody titers at parturition were 1:256, 1:64, and 1:512, respectively, in vaccinates and 1:128, 1:128, and 1:64, respectively, in controls. Median titers of CN antibodies against BHV-1 and BVDV types 1 and 2 were 1:1,280, 1:10,240, and 1:20,480, respectively, in vaccinates and 1:80, 1:1,280, and 1:2,560, respectively, in controls. CONCLUSIONS AND CLINICAL RELEVANCE Titers of antibodies against viral respiratory pathogens were significantly enhanced in both serum (BHV-1 and BVDV type 2) and colostrum (BHV-1 and BVDV types 1 and 2) in cattle receiving a killed virus vaccine (with no adverse reactions) before parturition. To maximize protection of bovine neonates, this method of vaccination should be considered.