Milk residues following multiple doses of meloxicam and gabapentin in lactating dairy cattle.

OBJECTIVE: To determine the influence of stage of lactation on the pharmacokinetics in milk when multiple doses of meloxicam were administered alone or in combination with gabapentin to postpartum (PP) and mid-lactation (ML) cows. ANIMALS: 8 postpartum and 8 mid-lactation dairy cows. METHODS: Cows were randomly divided into 2 groups (n = 8) which included 4 PP cows and 4 ML cows. Group I received only 6 oral daily doses of meloxicam (1.0 mg/kg for 6 doses). Group II received 6 oral daily doses of co-administered meloxicam (1.0 mg/kg) and gabapentin (20 mg/kg) for 6 doses. Meloxicam and gabapentin were quantified in plasma and milk samples by ultra-high-performance liquid chromatography-tandem mass spectrometry, and the pharmacokinetic analysis of milk and plasma was performed using a non-compartmental approach. RESULTS: Regardless of lactation status, dairy cattle administered multiple doses of meloxicam and/or gabapentin showed low drug residue concentrations and little accumulation in milk. The terminal plasma half-life of meloxicam was significantly increased (P < .02) in PP cows (12.9 hr) compared to ML cows (9.4 hr). The apparent terminal half-life in milk for meloxicam and gabapentin was not affected by stage of lactation. Co-administration of gabapentin did not alter plasma or milk concentrations of meloxicam. CLINICAL RELEVANCE: The results of this study suggest that milk from cows treated with multiple doses of meloxicam alone or in combination with gabapentin will have low drug concentrations and falls below our reported limit of detection for meloxicam or gabapentin 120 and 60 hours respectively, following the final dose regardless of their stage of lactation.

The pharmacokinetics of transdermal flunixin in lactating dairy goats.

Flunixin is a nonsteroidal anti-inflammatory drug approved for use in cattle to manage pyrexia associated with bovine respiratory disease, mastitis, and endotoxemia. In the United States, no nonsteroidal anti-inflammatory drugs are approved for use in goats, but analgesics are needed for management of painful conditions to improve animal welfare. The objective of this study was to evaluate the pharmacokinetics of transdermal flunixin in dairy goats to determine a milk withdrawal interval (WDI) to avoid violative residue contamination in the food supply. Six adult lactating dairy goats received 3.3 mg/kg of transdermal flunixin before milk, interstitial fluid (ISF), and blood samples were collected at various time points for 360 h. The samples were analyzed using tandem mass spectrometry to detect flunixin as well as the flunixin marker metabolite, 5-hydroxyflunixin followed by a pharmacokinetic WDI calculation using the US Food and Drug Administration tolerance limit method to propose safe residue levels in goat milk. The mean flunixin apparent plasma half-life was 21.63 h. The apparent milk half-life for 5-hydroxyflunixin was 17.52 h. Our findings provide a milk WDI of 60 h using the US Food and Drug Administration tolerance of 0.002 µg/mL (established for bovine milk) and a more conservative WDI of 96 h using a limit of quantification of 0.001 µg/mL following the extralabel use of transdermal flunixin in dairy goats.

Development and evaluation of a bovine lung-on-chip (bLOC) to study bovine respiratory diseases.

Purpose: Current air-liquid interface (ALI) models of bovine proximal airways have their limitations. They do not simulate blood flow necessary to mimic systemic drug administration, and repeated sampling requires multiple, independent cultures. A bovine lung-on-chip (bLOC) would overcome these limitations, providing a convenient and cost-effective model for pharmacokinetic or pathogenicity studies. Methods: Bovine pulmonary arterial endothelial cells seeded into the endothelial channel of an Emulate Lung-Chip were interfaced with bovine bronchial epithelial cells in the epithelial channel. Cells were cultured at ALI for up to 21 days. Differentiation was assessed by mucin quantification, phase-contrast light microscopy and immunofluorescence of cell-specific markers in fixed cultures. Barrier integrity was determined by FITC-labelled dextran 3-5 kDa permeability. To evaluate the model, endothelial-epithelial transport of the antibiotic drug, danofloxacin, was followed using liquid chromatography-mass spectrometry, with the aim of replicating data previously determined in vivo. Results: bLOC cultures secreted quantifiable mucins, whilst cilia formation was evident in the epithelial channel. Barrier integrity of the model was demonstrated by resistance to FITC-Dextran 3-5 kDa permeation. Bronchial epithelial and endothelial cell-specific markers were observed. Close to plasma, representative PK data for danofloxacin was observed in the endothelial channel; however, danofloxacin in the epithelial channel was mostly below the limit of quantification. Conclusion: A co-culture model of the bovine proximal airway was successfully generated, with potential to replace in vivo experimentation. With further optimisation and characterisation, the bLOC may be suitable to perform drug pharmacokinetic studies for bovine respiratory disease (BRD), and other applications.

Efficacy and production benefits following use of eprinomectin extended-release injection in pastured dairy heifers.

A study was conducted in grazing dairy heifers to assess anthelmintic efficacy and production responses in dairy heifers treated with a single injection of eprinomectin in an extended-release formulation over a 123 day-period. The study was conducted on a pasture-based dairy in the Southeastern United States (North Carolina) over the summer months. Sixty crossbred dairy heifers were weighed and randomly allocated into 2 groups. One group (n = 30) was given 5% eprinomectin subcutaneously in the cervical region while the other group (n = 30) was given an equivalent volume of saline. Calves were weighed every 30 days throughout the trial for calculation of average daily gain and differences in overall weight gain. In addition, fecal samples were collected at days 0, 30, 60, 90 and 123 for worm egg count and coproculture. Both groups of cattle had similar worm egg concentrations at the start of the study. However, the control group had increasing concentrations of fecal worm eggs throughout the summer months while the heifers that received eprinomectin had minimal fecal worm eggs. The primary parasite species identified in this study were Haemonchus placei, Cooperia species and Ostertagia. The heifers that received eprinomectin gained 105 + 2.8 kg during the 123-day study period, representing an average daily gain of 0.85 kg/day compared to 78.3 + 4.1 kg (0.64 kg/day) for the control group. This represented a 33 % increase in average daily gain associated with deworming. The results of this study indicate that a single dose of extended-release eprinomectin was sufficient to control parasites through a 123-day summer grazing season and that administration of the anthelmintic had a significant impact on weight gain.

Impact of bovine respiratory disease on the pharmacokinetics of danofloxacin and tulathromycin in different ages of calves.

Pneumonia is one of the most economically important respiratory diseases of calves and knowledge of the impact of clinical disease on pharmacokinetics (PK) in young calves is limited. This study was undertaken to investigate the efficacy and PK of two antibiotics, tulathromycin and danofloxacin, in two age groups of calves experimentally infected with Pasteurella multocida. Both danofloxacin, a fluoroquinolone antibiotic, and tulathromycin, a macrolide antibiotic is approved for the treatment of bovine respiratory disease (BRD). To evaluate potential influences of age and disease on drug distribution and elimination in calves, plasma, interstitial fluid (ISF), and pulmonary epithelial lining fluid (PELF) were analyzed for drug concentrations. Concentrations for both drugs in the PELF were estimated by a urea dilution assay of the collected bronchoalveolar lavage fluids. Age was determined to be a significant covariate for calves administered danofloxacin and tulathromycin for plasma PK parameters. For calves administered danofloxacin, the area under the curve (AUC) in the plasma was lower in 6-month old calves (18.9 ± 12.6 hr* µg/mL) vs. 3-week old calves (32.0 ± 8.2 hr* µg/mL). Clearance (CL/F) of danofloxacin was higher in 6-month old calves. In contrast, tulathromycin plasma concentrations were higher in 6 month old calves and CL/F was higher in 3-week old calves. Age did not significantly influence the ISF concentrations of danofloxacin or tulathromycin in calves with respiratory disease, unlike previous studies which reported higher ISF concentrations of danofloxacin and tulathromycin in 6-month old calves when compared to younger calves. PELF concentrations were higher than plasma and ISF for both danofloxacin and tulathromycin, but did not differ between age groups. Potential reasons for age-related differences on plasma concentration-time profiles and the impact of disease on the partitioning of the drug from the blood to the lungs and ISF as a function of age are explored.

Effect of age on plasma protein binding of several veterinary drugs in dairy calves 2.

The intent of this study was to determine what influence, if any, increasing age has on the binding of drugs to plasma proteins in cattle. Plasma from three different cohorts of calves were used. The first group (n = 20) had plasma samples taken at 1, 7 and 21 days of age. These were compared to results from a second group of calves at 8 weeks and third group sampled at 6 months of age. The plasma protein binding of danofloxacin, florfenicol, flunixin meglumine and tulathromycin was determined in vitro via microcentrifugation using three different drug concentrations spiked into the individual plasma samples derived from each calf. Albumin concentrations were lowest at 1 day of age as compared to plasma samples taken from 2 month old and 6 month old calves. There were significant decreases in alpha1-acid glycoprotein in calves until 21 days of age. However, statistically significant age-effects on plasma protein binding were not observed for any of the drugs evaluated in this study. Findings from these calves suggest that age is not an important factor in the binding of these drugs to plasma proteins.

Effect of age on the pharmacokinetics and distribution of tulathromycin in interstitial and pulmonary epithelial lining fluid in healthy calves.

OBJECTIVE To compare the plasma pharmacokinetics of tulathromycin between 3-week-old (preweaned) and 6-month-old (weaned) calves and to characterize the distribution of tulathromcyin into pulmonary epithelial lining fluid (PELF) and interstitial fluid (ISF) of preweaned and weaned calves following SC administration of a single dose (2.5 mg/kg). ANIMALS 8 healthy 3-week-old and 8 healthy 6-month-old Holstein steers. PROCEDURES A jugular catheter and SC ultrafiltration probe were aseptically placed in the neck of each calf before tulathromycin administration. Blood, ISF, and bronchoalveolar lavage fluid samples were collected at predetermined times before and after tulathromycin administration for quantification of drug concentration. A urea dilution method was used to estimate tulathromycin concentration in PELF from that in bronchoalveolar lavage fluid. Tulathromycin-plasma protein binding was determined by in vitro methods. Plasma pharmacokinetics were determined by a 2-compartment model. Pharmacokinetic parameters and drug concentrations were compared between preweaned and weaned calves. RESULTS Clearance and volume of distribution per fraction of tulathromycin absorbed were significantly greater for weaned calves than preweaned calves. Tulathromycin-plasma protein binding was significantly greater for weaned calves than preweaned calves. Maximum PELF tulathromycin concentration was significantly greater than the maximum plasma and maximum ISF tulathromycin concentrations in both groups. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that age affected multiple pharmacokinetic parameters of tulathromycin, likely owing to physiologic changes as calves mature from preruminants to ruminants. Knowledge of those changes may be useful in the development of studies to evaluate potential dose adjustments during treatment of calves with respiratory tract disease.

Invited review: Abomasal emptying in calves and its potential influence on gastrointestinal disease.

Creating the ideal nutrition program for calves is a demanding task that has undergone tremendous change in recent years. Products and technologies including novel milk replacers and automated calf feeding systems have been developed to facilitate the ability of dairy producers to feed for higher growth rates before weaning. The creation of new feeding programs and milk replacers has to be looked at carefully, not only from a nutrition point of view but also from the perspective of a potential effect on physiologic digestion and calf health. Abomasal emptying is a critical factor that may link nutrition and disease. The purpose of this article is to review both intrinsic and extrinsic factors that are responsible for abomasal emptying. Predominant extrinsic factors controlling abomasal emptying include meal volume, energy density, and osmolality along with the content and source of protein. This article also reviews experimental methods used to measure abomasal emptying in the calf including those that would be appropriate for use under field conditions. Among these methods, the use of ultrasonography and different absorption tests (d-xylose, acetaminophen) as tools to measure abomasal emptying are discussed. The relationship between abomasal emptying and disease is explored, particularly as it relates to abomasal bloat. Abomasal bloat is a complex syndrome that seems to be increasing in frequency and whose etiology likely at least partially involves slowing of abomasal emptying. Suggestions for minimizing the effect of feeding programs on abomasal emptying are explored as well as needs for future research.

Pharmacokinetics and tissue elimination of flunixin in veal calves.

OBJECTIVE To describe plasma pharmacokinetic parameters and tissue elimination of flunixin in veal calves. ANIMALS 20 unweaned Holstein calves between 3 and 6 weeks old. PROCEDURES Each calf received flunixin (2.2 mg/kg, IV, q 24 h) for 3 days. Blood samples were collected from all calves before the first dose and at predetermined times after the first and last doses. Beginning 24 hours after injection of the last dose, 4 calves were euthanized each day for 5 days. Plasma and tissue samples were analyzed by ultraperformance liquid chromatography. Pharmacokinetic parameters were calculated by compartmental and noncompartmental methods. RESULTS Mean ± SD plasma flunixin elimination half-life, residence time, and clearance were 1.32 ± 0.94 hours, 12.54 ± 10.96 hours, and 64.6 ± 40.7 mL/h/kg, respectively. Mean hepatic and muscle flunixin concentrations decreased to below FDA-established tolerance limits (0.125 and 0.025 µg/mL, respectively) for adult cattle by 3 and 2 days, respectively, after injection of the last dose of flunixin. Detectable flunixin concentrations were present in both the liver and muscle for at least 5 days after injection of the last dose. CONCLUSIONS AND CLINICAL RELEVANCE The labeled slaughter withdrawal interval for flunixin in adult cattle is 4 days. Because administration of flunixin to veal calves represents extralabel drug use, any detectable flunixin concentrations in edible tissues are considered a violation. Results indicated that a slaughter withdrawal interval of several weeks may be necessary to ensure that violative tissue residues of flunixin are not detected in veal calves treated with that drug.

Short communication: Characterization of the serologic response induced by vaccination of late-gestation cows with a Salmonella Dublin vaccine.

Diarrhea due to Salmonella infection is an important cause of neonatal calf diarrhea. The acquisition of passive immunity in the calf by vaccinating the dam has shown some success in previous studies; however, no data exists on the use of currently licensed vaccines in the United States. Therefore, the purpose of this study was to determine whether vaccinating cows in late gestation with a commercially available Salmonella Dublin vaccine would stimulate Salmonella-specific antibodies in the colostrum of cows at calving and whether these antibodies would be transferred to the calf. Thirty Holstein cows were vaccinated 3 wk before the end of lactation with a Salmonella enterica serovar Dublin vaccine, with a second dose given at dry-off. An additional 30 cows received only saline. Calves had a blood sample collected immediately after birth and were then fed fresh colostrum from their dam within 2 h of calving. A postcolostrum blood sample was collected 24 to 48 h later. Salmonella Dublin antibodies in colostrum as well as serum from the cows and calves were measured using an ELISA technique. Results of this study showed that vaccinated cattle had elevated Salmonella Dublin antibody titers at the time of calving (40.3 ± 9.1) as compared with control cows (-9.4 ± 1.1). Calves that received colostrum from vaccinated cattle also had a significant increase in Salmonella Dublin antibodies (88.5 ± 8.9) as compared with calves born to unvaccinated cows (-3.2 ± 1.2). This study demonstrated that the use of a commercially available Salmonella Dublin vaccine can stimulate antibodies that are passed on to the calf via colostral transfer. Further studies need to be done to determine whether these antibodies will offer protection against Salmonella challenge.

Short communication: Pharmacokinetics of intramammary hetacillin in dairy cattle milked 3 times per day.

Mastitis remains a critical disease in the dairy industry and the use of intramammary antibiotics plays a critical role in mastitis treatment. Hetacillin is currently approved as an intramammary antibiotic that is used to treat mastitis in dairy cows. It is approved for once a day administration and can be used for a total of 3 d. An increasing number of dairy farms are milking 3 times per day (instead of the traditional 2 times per day) and very little pharmacokinetic data exists on the use of intramammary drugs in a 3×system. The primary purpose of this study was to determine if once a day intramammary infusion of hetacillin is sufficient to maintain therapeutic drug concentrations in cattle milked 3 times per day. Eight Holstein cattle milked 3 times per day were used in this study. After collecting a baseline milk sample, each cow received intramammary infusions of hetacillin in the left front and right rear quarters once a day for 3 d. Milk samples from each of the treated quarters were collected at each milking and frozen until analysis. Milk samples were analyzed for ampicillin concentrations using an ultra-performance liquid chromatography method. All treated quarters had antibiotic concentrations well above the minimum inhibitory concentration (MIC) for gram-positive mastitis pathogens at 8 and 16 h postinfusion. Milk concentrations had fallen well below the MIC by the 24-h period (before the next infusion). All 8 cows in this study consistently had individual quarter milk ampicillin concentrations below the FDA tolerance of 0.01 µg/mL (10 ppb) within 48 h of the last infusion. Based on this study, milk ampicillin concentrations exceed the minimum inhibitory concentration required to inhibit the growth of 90% of organisms (MIC90) for at least 65% of the dosing interval, which is sufficient for once-daily dosing with most cases of gram-positive mastitis. Therefore, intramammary hetacillin should be an effective treatment for the vast majority of gram-positive mastitis pathogens when used according to label (once per day) in cows milked 3 times per day.

Comparison of pharmacokinetics and milk elimination of flunixin in healthy cows and cows with mastitis.

OBJECTIVE: To determine whether pharmacokinetics and milk elimination of flunixin and 5-hydroxy flunixin differed between healthy and mastitic cows. DESIGN: Prospective controlled clinical trial. ANIMALS: 20 lactating Holstein cows. PROCEDURES: Cows with mastitis and matched control cows received flunixin IV, ceftiofur IM, and cephapirin or ceftiofur, intramammary. Blood samples were collected before (time 0) and 0.25, 0.5, 1, 2, 4, 8, 12, 24, and 36 hours after flunixin administration. Composite milk samples were collected at 0, 2, 12, 24, 36, 48, 60, 72, 84, and 96 hours. Plasma and milk samples were analyzed by use of ultra-high-performance liquid chromatography with mass spectrometric detection. RESULTS: For flunixin in plasma samples, differences in area under the concentration-time curve and clearance were detected between groups. Differences in flunixin and 5-hydroxy flunixin concentrations in milk were detected at various time points. At 36 hours after flunixin administration (milk withdrawal time), 8 cows with mastitis had 5-hydroxy flunixin concentrations higher than the tolerance limit (ie, residues). Flunixin residues persisted in milk up to 60 hours after administration in 3 of 10 mastitic cows. CONCLUSIONS AND CLINICAL RELEVANCE: Pharmacokinetics and elimination of flunixin and 5-hydroxy flunixin in milk differed between mastitic and healthy cows, resulting in violative residues. This may partially explain the high number of flunixin residues reported in beef and dairy cattle. This study also raised questions as to whether healthy animals should be used when determining withdrawal times for meat and milk.

Implantation of an ultrafiltration device in the ileum and spiral colon of steers to continuously collect intestinal fluid.

Collection of fluid from the lumen of the gastrointestinal tract is commonly necessary for research projects, but presents challenges including intestinal motility and potential for leakage of intestinal contents. In this study, ultrafiltration collection devices were surgically implanted in the ileum and spiral colon of 12 steers for repeated collection of intestinal fluid over 48 hours. There were no significant complications associated with surgery or during the post-operative period, nor were there any significant pathologic changes found at necropsy 3 or 4 days post-surgery. Over 48 hours, we obtained 88% of the desired 212 samples. Only two devices failed to routinely collect samples. Use of ultrafiltration probes is a novel, consistent and humane method to repeatedly sample the gastrointestinal contents.

Fluid therapy in calves.

Early and aggressive fluid therapy is critical in correcting the metabolic complications associated with calf diarrhea. Oral electrolyte therapy can be used with success in calves, but careful consideration should be given to the type of oral electrolyte used. Electrolyte solutions with high osmolalities can significantly slow abomasal emptying and can be a risk factor for abomasal bloat in calves. Milk should not be withheld from calves with diarrhea for more than 12 to 24 hours. Hypertonic saline and hypertonic sodium bicarbonate can be used effectively for intravenous fluid therapy on farms when intravenous catheterization is not possible.

Effect of orally administered electrolyte solution formulation on abomasal luminal pH and emptying rate in dairy calves.

OBJECTIVE: To determine the effects of 3 commercially available, orally administered electrolyte solutions (OAEs) on abomasal luminal pH and emptying rate in dairy calves, compared with the effect of orally administered milk replacer. DESIGN: Randomized crossover study. ANIMALS: 6 male dairy calves (age, 12 to 31 days). PROCEDURES: Calves were surgically instrumented with an abomasal cannula and were administered 4 treatments in randomized order: all-milk protein milk replacer, high-glucose high-bicarbonate OAE, high-glucose high-bicarbonate OAE containing glycine, and low-glucose OAE containing acetate and propionate. Abomasal luminal pH was measured with a miniature glass pH electrode prior to treatment administration and every second afterward for 24 hours. RESULTS: Feeding of orally administered milk replacer resulted in a rapid increase in mean abomasal luminal pH from 1.3 to 5.8, followed by a gradual decrease to preprandial values by 8 hours afterward (mean 24-hour pH, 3.2). High-glucose high-bicarbonate OAEs caused a large and sustained increase from 1.3 to 7.5 (mean 24-hour pH, 4.1 for the solution without glycine and 3.5 for the solution with glycine). In contrast, feeding of the acetate-containing OAE was followed by only a mild and transient increase (mean 24-hour pH, 2.1); luminal pH returned to preprandial values by 3 hours after ingestion. CONCLUSIONS AND CLINICAL RELEVANCE: Ingestion of a bicarbonate-containing OAE resulted in sustained abomasal alkalinization in dairy calves. Because persistently high abomasal luminal pH may facilitate growth of enteropathogenic bacteria, administration of OAEs containing a high bicarbonate concentration (> 70mM) is not recommended for calves with diarrhea.

Pharmacokinetics and tissue elimination of tulathromycin following subcutaneous administration in meat goats.

OBJECTIVE: To determine the tissue depletion profile of tulathromycin and determine an appropriate slaughter withdrawal interval in meat goats after multiple SC injections of the drug. ANIMALS: 16 healthy Boer goats. PROCEDURES: All goats were administered tulathromycin (2.5 mg/kg, SC) twice, with a 7-day interval between doses. Blood samples were collected throughout the study, and goats were euthanized at 2, 5, 10, and 20 days after the second tulathromycin dose. Lung, liver, kidney, fat, and muscle tissues were collected. Concentrations of tulathromycin in plasma and the hydrolytic tulathromycin fragment CP-60,300 in tissue samples were determined with ultrahigh-pressure liquid chromatography-tandem mass spectrometry. RESULTS: The plasma profile of tulathromycin was biphasic. Absorption was very rapid, with maximum drug concentrations (1.00 ± 0.42 µg/mL and 2.09 ± 1.77 µg/mL following the first and second doses, respectively) detected within approximately 1 hour after injection. Plasma terminal elimination half-life of tulathromycin was 61.4 ± 14.1 hours after the second dose. Half-lives in tissue ranged from 2.4 days for muscle to 9.0 days for lung tissue; kidney tissue was used to determine the withdrawal interval for tulathromycin in goats because it is considered an edible tissue. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of the tissue tolerance limit in cattle of 5 ppm (µg/g), the calculated withdrawal interval for tulathromycin would be 19 days following SC administration in goats. On the basis of the more stringent guidelines recommended by the FDA, the calculated meat withdrawal interval following tulathromycin administration in goats was 34 days.

Evaluation of a Serpens species bacterin for treatment of digital dermatitis in dairy cattle.

Digital dermatitis is a major cause of lameness in many dairy herds and represents a detriment to milk production, reproductive efficiency, productive lifespan and welfare. The purpose of this study was to evaluate the therapeutic use of a Serpens species bacterin in a dairy herd known to have a significant prevalence of lameness due to digital dermatitis. Seventy-six mature lactating Holsteins were enrolled in this study. Group 1 (n=38) received three injections of a Serpens species bacterin at four-week intervals (weeks 0, 4, and 8) while group 2 (n=38) received only adjuvant. Blood samples were obtained prior to the first injection at week 0 and again at week 12 to evaluate antibody responses. Locomotion and digital dermatitis lesion measurements were performed at weeks 0, 12 and 18. Although Serpens-associated antibody titers increased from week 0 to 12 in vaccinated cows; the prevalence of digital dermatitis, the percentage of cows identified as clinically lame and the average width of digital dermatitis lesions did not differ from week 0 to 12 or from week 0 to 18 between groups. The results of this study indicate a lack of any clinical efficacy associated with vaccination in this herd, although inoculation with the bacterin did stimulate a measurable antibody response.

Efficacy of amprolium for the treatment of pathogenic Eimeria species in Boer goat kids.

This study evaluated the efficacy of two different doses of amprolium in goats heavily infected with pathogenic Eimeria species. Forty Boer goat kids ranging from 3 to 5 months of age with naturally occurring coccidiosis were randomly divided into 2 groups and treated orally with amprolium at doses of 10mg/kg daily for 5 days (n=20) or 50mg/kg daily for 5 days (n=20). The Eimeria oocyst per gram concentrations were significantly reduced on day 7 in the kids that received amprolium at 50mg/kg, however oocyst concentrations were not significantly reduced in goats that received the 10mg/kg dose. Out of 100 Eimeria oocysts identified from a pooled fecal sample, E. christenseni was the most frequently identified (52%) coccidial species present. The results of this trial indicate that amprolium can be an effective treatment for pathogenic Eimeria species in goat kids, however higher and extralabel doses (50mg/kg) should be used.