Objective—To determine whether dietary supplementation with ammonium chloride would affect urine pH or urinary fractional excretion (FE) of electrolytes in goats fed grass hay.
Animals—15 yearling castrated male goats.
Procedures—In the dose response study, 3 yearling goats fed orchard grass hay and water ad libitum were administered ammonium chloride at either 200, 400, or 500 mg/kg (91, 182, or 227 mg/lb), PO, every 24 hours. In the FE study, 8 goats fed orchard grass hay were randomly divided into either a treatment (n = 4) or a control group (4). In the treatment group, ammonium chloride was administered at 450 mg/kg (2.25% of dry matter intake [DMI]), PO, every 24 hours for 8 days. The FE of electrolytes was compared between groups; FE measurements were also determined for 4 client-owned goats fed alfalfa hay.
Results—Ammonium chloride administered at 450 mg/kg (2.25% of DMI) achieved and maintained urine pH < 6.5 for 24 hours. Goats fed orchard grass hay with ammonium chloride supplementation had significantly higher FE of calcium and chloride than did goats fed orchard grass hay without supplemental ammonium chloride.
Conclusions and Clinical Relevance—Dietary ammonium chloride supplementation at a dose of 450 mg/kg may be necessary to achieve a urine pH < 6.5 in goats. Further studies of ammonium chloride supplementation and urolithiasis in goats fed low-calcium diets are indicated.
Case Description—6 lactating dairy goats were examined because of acute mastitis.
Clinical Findings—Goats were considered to have endotoxemia on the basis of physical examination and clinicopathologic findings. The affected udder halves had gangrenous discolored distal portions with sharp demarcations from grossly normal tissue proximally. Udder secretions from the affected sides were serosanguineous in all cases. A Bacillus sp was isolated in pure cultures in all cases. In 1 case, the Bacillus sp was identified as Bacillus cereus.
Treatment and Outcome—Goats were treated for mastitis and endotoxemia with polyionic IV fluid therapy, systemic and intramammary antimicrobial administration, anti-inflammatory drug administration, and other supportive treatment. All goats survived to discharge. All except 1 goat had follow-up information available. The affected udder halves sloughed in 1 to 2 months following discharge. In subsequent lactations after the mastitis episodes, milk production in 2 of 5 goats was above the mean, as determined on the basis of Dairy Herd Improvement records, and 3 of 5 goats were voluntarily withdrawn from lactation. All 5 goats had successful kiddings after the Bacillus mastitis episode.
Conclusions and Clinical Relevance—Bacillus sp should be considered as a causative agent in goats with gangrenous mastitis, especially when the Bacillus sp is isolated in a pure culture. Antimicrobial sensitivity testing is recommended for selection of an appropriate antimicrobial for treatment. Prognosis for survival appears to be good, although milk production may be decreased.
Objective—To determine associations between age, sex, breed, and month and year of admission and the diagnosis of lead toxicosis in cattle.
Design—Retrospective case-control study.
Sample Population—Records of all cattle evaluated at North American veterinary teaching hospitals during the years 1963 to 2002, which were available through the Veterinary Medical Database.
Procedures—Logistic regression was used to evaluate the associations between postulated risk factors and the occurrence of lead toxicosis in cattle and predict the occurrence of the diagnosis of lead toxicosis in cattle.
Results—413 cases of lead intoxication and 202,363 control cattle were identified and met the inclusion criteria. Cattle < 4 years of age were at increased risk for the diagnosis of lead intoxication relative to cattle ≥ 4 years of age. Cattle ≥ 2 months and < 6 months of age had the greatest risk for lead intoxication (odds ratio, 12.3). Angus cattle were at greater risk for toxicosis (odds ratio, 1.95), compared with other breeds. The risk of lead toxicosis was greater before 1985 (odds ratio, 1.94) than the risk thereafter. The risk of lead toxicosis diagnosis was greatest in the months of May, June, July, and August.
Conclusions and Clinical Relevance—Lead toxicosis in cattle was associated with age < 4 years and the Angus breed. A seasonal pattern existed with peak occurrence in the late spring and summer. The occurrence of lead toxicosis has declined over time.