OBJECTIVE To determine serum and tissue concentrations of gallium (Ga) after oral administration of gallium nitrate (GaN) and gallium maltolate (GaM) to neonatal calves.
ANIMALS 8 healthy neonatal calves.
PROCEDURES Calves were assigned to 1 of 2 groups (4 calves/group). Gallium (50 mg/kg) was administered as GaN or GaM (equivalent to 13.15 mg of Ga/kg for GaN and 7.85 mg of Ga/kg for GaM) by oral gavage once daily for 5 days. Blood samples were collected 0, 0.25, 0.5, 1, 2, 4, 8, 12, and 24 hours after Ga administration on day 1; 4 and 24 hours after Ga administration on days 2, 3, and 4; and 4, 12, and 24 hours after Ga administration on day 5. On day 6, calves were euthanized and tissue samples were obtained. Serum and tissue Ga concentrations were measured by use of mass spectrometry.
RESULTS Data were adjusted for total Ga dose, and comparisons were made between the 2 groups. Calves receiving GaM had a significantly higher dose-adjusted area under the curve and dose-adjusted maximum serum Ga concentration than did calves receiving GaN. Despite receiving less Ga per dose, calves receiving GaM had tissue Ga concentrations similar to those for calves receiving GaN.
CONCLUSIONS AND CLINICAL RELEVANCE In this study, calves receiving GaM had significantly higher Ga absorption than did calves receiving GaN. These findings suggested that GaM might be useful as a prophylactic agent against Mycobacterium avium subsp paratuberculosis infection in neonatal calves. (Am J Vet Res 2016;77:151–155)
To assess the prevalence of tubular genital tract neoplasia in does evaluated at 2 veterinary teaching hospitals; describe the main clinical, surgical, and histopathologic or necropsy findings in affected does; and assess factors potentially associated with short-term prognosis in these animals.
Medical records of 2 veterinary teaching hospitals were searched to identify does with neoplasia of the tubular genital tract. Signalment; history; physical and diagnostic imaging results; biopsy, surgery, and necropsy findings; and short-term outcome were recorded. Age and breed frequencies for the sample were compared with those of the overall hospital population, and variables of interest were tested for associations with a diagnosis of adenocarcinoma and with short-term outcome by statistical methods.
Median age at hospital admission (10 years) was greater for the study sample than for the general hospital population (2 years). Pygmy goats were overrepresented (22/42 [52%]). Common reasons for evaluation were bloody vaginal discharge or hematuria and abdominal straining. Adenocarcinoma (13/42 [31%]), leiomyoma (13 [31%]), and leiomyosarcoma (11 [26%]) were the most common tumors. Does with distant metastasis had greater odds of a diagnosis of adenocarcinoma (OR, 40.5) than does without distant metastasis. In the analysis adjusted for hemorrhagic discharge, odds of euthanasia for does with straining were 13 times those for does without straining. In the analysis adjusted for straining status, does with hemorrhagic discharge had almost 7 times the odds of euthanasia for does without this finding. The survival-to-discharge rate was low (13/42 [31%]).
CONCLUSIONS AND CLINICAL RELEVANCE
The frequency of adenocarcinomas in the study sample was unexpectedly high. Further research is needed to confirm the study findings.
Objective—To evaluate the in vitro susceptibility of various field isolates of Mycobacterium avium subsp paratuberculosis (MAP) to gallium nitrate.
Sample—10 isolates of MAP, including 4 isolated from cattle, 2 isolated from bison, 1 isolated from an alpaca, and 3 isolated from humans.
Procedures—The in vitro susceptibility to gallium nitrate was tested by use of broth culture with detection of MAP growth by means of a nonradiometric automated detection method. For each MAP isolate, a series of 7 dilutions of gallium nitrate (concentrations ranging from 200 to 1,000μM) were tested. Gallium nitrate was considered to have caused 90% and 99% inhibition of the MAP growth when the time to detection for culture of the MAP stock solution and a specific concentration of gallium nitrate was delayed and was similar to that obtained for culture of the MAP stock solution (without the addition of gallium nitrate) diluted 1:10 and 1:100, respectively.
Results—Gallium nitrate inhibited MAP growth in all 10 isolates. The susceptibility to gallium nitrate was variable among isolates, and all isolates of MAP were inhibited in a dose-dependent manner. Overall, the concentration that resulted in 90% inhibition ranged from < 200μM for the most susceptible isolates to 743μM for the least susceptible isolates.
Conclusions and Clinical Relevance—Gallium nitrate had activity against all 10 isolates of MAP tested in vitro and could potentially be used as a prophylactic agent to aid in the control of MAP infections during the neonatal period.
Objective—To evaluate therapeutic efficacy of a high
extralabel dose of ceftiofur for treatment of experimental
salmonellosis in neonatal calves.
Animals—Forty-two 1- to 4-day-old Holstein bull
Procedure—36 calves were orally challenged with
Salmonella enteritica serovar Typhimurium (6.5 × 108
colony-forming units). Six additional calves were
retained as nonmedicated nonchallenged control
calves. Four days following Salmonella challenge, surviving
calves were randomly allocated to ceftiofurtreated
(5 mg/kg, IM, q 24 h) or nonmedicated control
groups. Calves assigned to the treated group were
medicated daily for 5 days starting on day 4 after challenge.
Calves were monitored for 18 days following
Salmonella challenge. Outcome assessments included
clinical parameters (attitude, appetite, fecal characteristics,
and rectal temperature), mortality rate, and
quantitative Salmonella culture of fecal samples,
mesenteric lymph nodes, and cecal contents.
Results—Ceftiofur treatment was associated with a
significant decrease in rectal temperature and diarrhea.
Three of 15 medicated calves and 4 of 14 nonmedicated
calves died or were euthanatized between
days 4 and 18. A significant decrease in fecal shedding
of Salmonella organisms was observed in treated
calves, compared with non-medicated calves.
Salmonella organisms were isolated from all 10 nonmedicated
calves at necropsy, whereas no
Salmonella organisms were isolated from 5 of 12
Conclusions and Clinical Relevance—Treatment of
salmonellosis in neonatal calves with a high extralabel
dose of ceftiofur (5 mg/kg, IM, q 24 h) promotes animal
welfare, reduces fecal shedding of Salmonella
organisms, and may promote clearance of Salmonella
infections when plasma ceftiofur concentrations are
maintained above minimal inhibitory concentrations.
(Am J Vet Res 2003;64:918–925)