Pharmacokinetics of multiple doses of transdermal flunixin meglumine in adult Holstein dairy cows

A transdermal formulation of the nonsteroidal anti‐inflammatory drug, flunixin meglumine, has been approved in the United States and Canada for single‐dose administration. Transdermal flunixin meglumine was administered to 10 adult Holstein cows in their second or third lactation at the label dose of 3.33 mg/kg every 24 hr for three total treatments. Plasma flunixin concentrations were determined using high‐pressure liquid chromatography with mass spectroscopy (HPLC ‐MS ). Pharmacokinetic analysis was completed on each individual animal with noncompartmental methods using computer software. The time to maximum drug concentration (T max) was 2.81 hr, and the maximum drug concentration was 1.08 μg/ml. The mean terminal half‐life (T½) was determined to be 5.20 hr. Clearance per fraction absorbed (Cl/F) was calculated to be 0.294 L/hr kg^?1, and volume of distribution of fraction (V z/F ) absorbed was 2.20 L/kg. The mean accumulation factor was 1.10 after three doses. This indicates changes in dosing may not be required when giving multiple doses of flunixin transdermal. Further work is required to investigate the clinical efficacy of transdermal flunixin after multiple daily doses.     

The use of ultrasonography in the reproductive evaluation of boars

The objective was to study the use of ultrasound as a complementary test in the breeding soundness evaluation in male pigs and study the pattern of echogenicity of the testicular parenchyma in boars of different racial groups. Twenty‐six adult boars from four different racial groups were used, 10 from the Piau breed (group 1), four from the commercial and finishing group (group 2), six Pietrain breed (group 3) and six from the Duroc breed (group 4). All animals were evaluated for breeding soundness evaluation and the ultrasound examination of the testicles. The groups of animals that were evaluated showed no difference in the main semen parameters that were evaluated, except for the sperm volume, concentration of the ejaculated sperm and the supravital staining; the lowest figures were for the animals from the Piau breed (group 1). In relation to the testicular biometrics, Duroc animals (group 4) had a greater scrotal width compared to the other groups. But when we assessed the intensity of pixels of the testicles, there was a difference between groups. The groups 2 (finishing animals), 3 (Pietrain) and 4 had no difference between themselves. Group 3 had greater pixel intensity in relation to group 1. Of the 26 animals studied, five showed an abnormality during ultrasound evaluation, like hydrocele, hyperechoic mass in the testicular parenchyma, cyst in the head of the epididymis and the presence of fluid in the head and tail of the epididymis. The various animal groups studied did not differ in the principal reproductive parameters evaluated, showing that despite the great variability of reproductive traits between breeds and within the same breed, the breeding soundness evaluation, the more complete it is, is essential for the selection of breeders and the ultrasonography of the reproductive system becomes an important addition in this examination.     

Cellulase Supplementation Does Not Improve the Digestibility of a High-Forage Diet in Horses

Six mature Arabian geldings were used in a two-period crossover study to investigate the effects of cellulase supplementation on fiber digestion. Horses were randomly assigned to either a control (CO; n = 3) or a cellulase (CE; n = 3) treatment for the first period and then treatments were switched for period 2. Each period consisted of a 10-day diet adaptation followed by a 3-day total fecal collection. The enzyme mixture contained 40,000 cellulase units/g and was fed at a rate of 3 g/day split evenly between two feedings. During the diet adaptation period, horses had ad libitum access to timothy hay and were also fed 165 g whole oats as a carrier for the supplement. When eating the CO treatment, horses consumed 16% more hay than when on the CE treatment (P = .004). Fecal output also tended to be greater when horses consumed the CO treatment as compared with CE treatment (P = .07). No differences were found between treatments for fecal percent dry matter (DM%), fecal neutral detergent fiber (NDF), fecal acid detergent fiber (ADF), fecal nitrogen (N), or fecal gross energy (GE). There was a trend for horses consuming the CO treatment to digest more NDF than when consuming the CE treatment (34.6% ± 1.5 vs 31% ± 1.5; P = .07). Horses also digested a greater %ADF, %N, and Mcal of energy when consuming the CO treatment than when consuming the CE treatment (P < .05). Cellulase addition to a hay-based horse diet decreased digestion of fiber components.     

Association of racing performance with specific abnormal radiographic findings in Thoroughbred yearlings sold in Texas

The objective of this prospective study was to determine the association between presence of abnormal radiographic findings attributed to orthopedic disorders of development (ARF) with subsequent performance among yearlings in Texas. The study population was 348 yearlings offered for sale at the Texas Summer Yearling Sale during 2002 and 2003 for which presale radiographs of limbs were available for review. Radiographs of yearlings were reviewed and presence of ARF were recorded. Additionally, the following data were recorded for each horse: identifiers [name of dam, name of sire, hip number, and name (when available)], year of sale, state of birth, and sales price. Subsequent performance data were obtained for each horse at the conclusion of their 2^nd and 3^rd years of life. Results indicated that no ARF was significantly associated with performance outcomes. Lesions of the proximal dorsal aspect of the sagittal ridge of the 3^rd metacarpus/metatarsus resulted in significantly lower sales prices than either horses without this ARF or horses without any ARF. In conclusion, multiple radiographic abnormalities of Thoroughbred yearlings were not associated with reduced performance during the first 2 years of the racing careers of horses studied. Presence of some abnormalities, however, may be associated with reduced sales price.