Epidemiologic evaluation of encephalitic listeriosis in goats.

OBJECTIVE: To evaluate host and environmental factors associated with the development of encephalitic listeriosis in goats. DESIGN: Retrospective analysis of diagnostic laboratory records and survey of veterinarians and goat producers. SAMPLE POPULATION: 355 goat herds accessible through laboratory records; 38 veterinarians who treated goats and 76 goat producers. PROCEDURE: Data regarding breed and use for goats affected with encephalitic listeriosis were obtained from surveys and case follow-up information. Listeria monocytogenes isolates from the brains of 7 affected goats were serotyped and subjected to DNA restriction analysis. RESULTS: Odds ratio for the development of encephalitis listeriosis in Angora (mohair-producing) goats was 22.9 by use of diagnostic laboratory records. Survey also revealed a high prevalence in herds of Angora and other breeds that subsisted on woody browse, although Angora goats feeding predominantly on hay or pasture were not affected. Listeria monocytogenes isolates from 4 Angora goats in 3 herds differed in DNA restriction patterns, although the pattern was identical in 3 other goats from another herd. CLINICAL IMPLICATIONS: Encephalitic listeriosis can be observed in all goat breeds, but a lifestyle of heavy browse consumption seems important to the development of disease in some herds.

Effect of Re-17 mutant Salmonella typhimurium bacterin toxoid on clinical coliform mastitis.

The objective of this study was to test the hypothesis that the incidence and severity of clinical coliform mastitis could be decreased by Re-17 mutant Salmonella typhimurium bacterin toxoid. Holstein-Friesian cows from two Arizona dairies were selected for this study based on July through November projected calving dates; peak lactation occurred during the period of highest rainfall and peak environmental stress. The cows were randomly assigned to either a vaccinate or a control group, and 1292 cows were paired by herd, parity, calving date, and milk yield. The 646 vaccinates were injected twice during the third trimester of pregnancy with an Re-17 mutant S. typhimurium bacterin toxoid, and the 646 controls were not vaccinated. Vaccinated cows had significantly fewer clinical cases of coliform mastitis with positive coliform cultures and had lower culling rate from coliform mastitis than control cows during the first 5 mo of lactation. During the same period, the mortality rate from clinical coliform mastitis was 75% less in the vaccinated clinical coliform mastitic group than in the control group. Incidence of mastitis increased with advancing parity. The Re-17 mutant Salmonella typhimurium bacterin toxoid provided cross-protection against coliform mastitis; incidence and severity of clinical coliform mastitis were significantly lowered during the first 5 mo of lactation.

Evaluation of edetate and thiamine for treatment of experimentally induced environmental lead poisoning in cattle.

Twenty mature Holstein cows were randomized into 5 treatment groups. Cows of groups 2 to 5 were given 2 mg of elemental Pb/kg of body weight for 28 days. Clinical signs of plumbism were scored, and blood for Pb, progesterone, and hematologic analyses was collected weekly. Cows also were examined weekly for anomalous ovarian cycles. Starting on study day 28, cows in group 3 were treated once daily with 2 mg of thiamine HCl/kg (IM) for 13 days, cows in group 4 were treated twice daily with 62 mg of Na2,Ca-EDTA/kg (IV) for 4 days, and cows in group 5 were given thiamine (dosage regimen the same as for group 3) plus Na2,Ca-EDTA (dosage regimen the same as for group 4). On study days 96 through 139, cows were slaughtered in a commercial abattoir and samples of blood, skeletal muscles, bones, liver, and kidneys were collected and assayed for Pb concentration. Thiamine was not effective in reducing blood Pb concentration, and treatment with Na2,Ca-EDTA and thiamine plus Na2,Ca-EDTA was effective in reducing the concentration of Pb in blood. However, treatment with thiamine was more effective than treatment with Na2,Ca-EDTA or thiamine plus Na2,Ca-EDTA in inducing remission of clinical signs of plumbism. The concentration of Pb in blood was significantly (P less than 0.05) correlated to the concentration of Pb in liver, kidneys, skeletal muscles, and bones. Significant (P less than 0.05) relationship existed between number of days from Pb exposure to slaughter and concentration of Pb in blood, liver, and skeletal muscles. Exposure to Pb did not significantly alter CBC values.(ABSTRACT TRUNCATED AT 250 WORDS)

Zinc deficiency in sheep and goats: three field cases.

Zinc deficiency was diagnosed in 2 flocks of sheep and a herd of goats. Alopecia and eating of wool were observed. Skin lesions were hyperkeratosis and parakeratosis. Abnormal hoof growth and a closed stance with arched back and bowed hindlimbs were seen. Anorexia, depression, and foot soreness diminished quickly after zinc supplementation. Skin lesions healed and hair and wool growth resumed. A cause for the deficiency could not be established.