Efficacy of daily amitraz on generalised demodicosis in dogs

Fifty dogs with generalised demodicosis were treated with daily applications of 0·125 per cent amitraz solution over half the body. This was applied once a day, alternating the body half treated. Nine dogs were lost to follow-up; the remaining dogs were classified as either a success (25 dogs, 61 per cent) or a failure (16 dogs, 39 per cent) according to their response to treatment. Eight of the failures were due to persistent demodicosis and eight relapsed within one year after treatment. All eight of the relapsed dogs were cured after a second course of daily amitraz treatment. For the 25 dogs considered treatment successes, the median duration of treatment was 6·5 weeks (range, three weeks to nine months), and the median interval from completion of treatment to last post treatment evaluation was 3·4 years (range, two to four-and-a-half-years). Including the eight dogs that were cured after retreatment, the daily amitraz applications were curative in 33 of 41 dogs (80 per cent) with generalised demodicosis.     

Pharmacokinetics and bioequivalence of parenterally administered doramectin in cattle

Plasma concentrations of doramectin in 40 cattle dosed by subcutaneous (sc) or intramuscular (i.m.) injection (200 μg/kg) were compared to assess the bioequivalence of the two routes of administration. Peak concentration ( C _max), and areas under the concentration curve ( AUC_0– ) were determined from plasma concentrations. Animals treated by the sc route showed a mean AUC_0– of 457 ± 66 ng±day/mL (± SD) and a mean C _max of 27.8 ± 7.9 ng/mL. Results from the i.m. treatment group showed a mean AUC _0– of 475 ± 82 ng-day/mL and a mean C _max of 33.1 ± 9.0 ng/mL Absorption constants ( k _a) determined by modelling were 0.542 ± 0.336 day^-1after sc administration and 0.710 ± 0.357 day^-1after i.m. administration. The 90% confidence limits on the difference between mean AUC _0– values for the sc and i.m. groups fell within 20% of the mean value for the subcutaneous group. C _max was somewhat greater for the i.m. route. The 90% confidence limits on the difference in mean In ( T _max+1) also fell within 20% of the mean sc value. Based on this analysis, bioequivalence of the sc and i.m. formulation has been established.     

Jejunal Intussusception: A Complication of Functional End-to-End Stapled Anastomoses in Two Ponies

Jejunojejunal intussusception occurred after jejunal resection and stapled functional end-to-end anastomosis in two pony mares. In both mares, the lead point of the intussusception was the stapled functional end-to-end (FEE) anastomosis. The stapled free ends of jejunum were oversewn with an inverting suture pattern. A possible explanation for development of the intussusception was the acute angle created in the intestine by the FEE anastomsis. This angulation may have impaired flow of ingesta causing motility changes that predisposed the site to intussusception. Because the oversewn blind intestinal ends acted as the lead point for formation of the intussusception, it may be inadvisable to oversew the stapled anastomotic ends.     

Changes in taurine levels in response to repeated administration of the β2-agonist salbutamol in lambs

Repeated oral administration of salbutamol to lambs for 28 days was found to decrease levels of taurine significantly in the serum and heart, and the mean excretion of taurine into urine was significantly less than in controls. Serum urea, low density lipoprotein and high density lipoprotein were also significantly reduced. Consistent with these changes, fat content in muscle was reduced, whereas protein content was not significantly changed. Body weight was not significantly changed by salbutamol treatment but heart and kidney weights (relative to body weight) were significantly increased. Salbutamol excretion in urine was relatively constant and residues were detected in certain organs and tissues, notably liver, bile and kidney. Changes in urinary and serum taurine level may reflect subtle changes in protein metabolism not detectable as changes in body weight or gross protein content.     

A Transtracheal Catheter for Recording the Static Tracheal Pressure in the Exercising Horse

After giving an account of the principles of pressure measurement in flowing air and a review of the literature on tracheal catheters, the authors describe the construction, the introduction and the function of their own transtracheal catheter. This is a teflon catheter with several side–ports which is introduced into the cervical trachea by a guide technique. After introduction, the catheter is stiffened by the insertion of 2 steel wires. The catheter was studied in model experiments concerning: a) the ability to measure the static pressure in flowing air, and b) the dynamic accuracy of a recording system built up around the catheter.The results indicated that the intratracheal pressure sensed in exercising horses well reflected the static pressure, and that the dynamic accuracy of the recording system was good to about 60 Hz. The present technique of recording the intratracheal pressure was used on 122 occasions in 69 exercising horses with only one complication referable to the catheter occurring. The transtracheal route of catheterisation may be superior, as catheters introduced by this route do not appear to influence the function of the pharynx and larynx. In contrast, nasotracheal catheters that traverse the larynx, might interfere with the respiratory function. kw|Keywords|k]upper airway obstruction k]frequency response     

Estimation of genetic correlations between racing times recorded at different racing distances by restricted maximum likelihood in Thoroughbred racehorses

SUMMARY: Genetic correlations between racing times on track type (turf and dirt), and at racing distances on turf (1200 m, 1400 m, 1600 m, 1800 m, and/or 2000 m) and dirt (1000 m, 1200 m, 1400 m, 1600 m, 1700 m, and/or 1800 m) tracks, were estimated in Thoroughbred horses. (Co)variance components were estimated using multiple-trait derivative-free restricted maximum likelihood (MTDFREML). The data used were collected by the Japan Racing Association from 1992 to 1993. The generation 2 pedigree information was preferable for (co)variance estimates. The genetic correlations between racing times on turf and dirt tracks ranged from 0.69 to 0.31 (average 0.51). The genetic correlations between racing distances ranged from 0.68 to 1.00 (average 0.85) and from 0.53 to 1.00 (average 0.88) on turf and dirt tracks, respectively. These results suggest that the racing time per 100 m can be used for horse genetic evaluation within one track type. ZUSAMMENFASSUNG: Sch?tzung genetischer Korrelationen zwischen Rennzeiten von Vollblüternüber verschiednen Distanzen mittels restringierter Genetische Korrelationen zwischen Rennzeiten auf Rasen- und Erdbahnen, Renndistanzen auf Rasen- (1200, 1400, 1600, 1800 und 2000 m) und Erdbahnen (1000, 1200, 1400, 1600, 1700 und 2000 m) wurden für Vollblüter gesch?tzt. (Co)Varianzkomponenten wurden mittels Mehr-Merkmal Ableitungsfreier Restringierter Maximum Likelihood (MTDFREML) gesch?tzt. Die Unterlagen wurden von der Japanischen Renn Vereinigung 1992 und 1993 gesammelt. Generation 2 Abstammungsinformation war für die Co-Varianzsch?tzung günstig. Genetische Korrelationen zwischen Rennzeiten auf Rasen und auf Erdbahnen waren zwischen 0.69 und 0.31 (Durchschnitt 0.51), jene zwischen Distanzen zwischen 0.68 und 1.00 (Durchschnitt 0.85) und zwischen 0.53 und 1.00 (Durchschnitt 0.88) auf Rasen und Erdbahnen. Die Ergebnisse zeigen, da? Rennzeit per 100 m zur Bewertung der Pferde geeignet ist.     

Effects of selection on food intake in the adult mouse

SUMMARY: Replicated lines of mice were selected High and Low for adjusted food intake and contemporaneous control lines were maintained. The selection criterion was food intake between 8 and 10 weeks, adjusted by phenotypic regression on mean body weight at 8 and 10 weeks of age to reduce correlated changes in body weight. Responses are given for the first 23 generations of selection, after which adjusted food intake had diverged by a factor of 1.7-1.95. A small correlated response in body weight occurred and mice from the High line were slightly heavier: at 10 weeks of age body weight had diverged by a factor of 1.09-1.11. The realized within-family heritability varied between the replicates from 0.16-0.27 from which a mean estimated mass selection heritability (h(2) = 0.35±0.05) was derived. Mice from the Low line were fatter, however not significantly, because of a High between replicate variance (p > 0.05). Differences in growth over the selection period may account for around 5% of the divergence and increased maintenance costs associated with the larger lean mass of the high lines may explain a further 5%. Mice from the High lines spilled significantly (p < 0.05) more food which accounted for 23% of the divergence in apparent food intake. The heat increment of feeding, brown adipose tissue activity and locomotor activity all appear to be unchanged. ZUSAMMENFASSUNG: Auswirkungen der Selektion auf Futteraufnahme in der adulten Maus In einem Experiment mit Wiederholungen wurden M?uselinien auf hohe und niedrige korrigierte Futteraufnahme selektiert und korrespondierende Konttrollen gehalten. Das Selektionskriterium war die Futteraufnahme im Alter von 8 bis 10 Wochen, die mittels ph?notypischer Regression korrigiert wurde, um die K?rpermasse m?glichst konstant zu halten. Der direkte Selektionserfolg über die ersten 23 Generationen ist beschrieben. Die Linien divergierten zu diesem Zeitpunkt bezüglich des Selektionsmerkmals um 70 bis 95%. In der K?rpermasse trat ein geringfügiger korrelierter Selektionserfolg auf. Die Tiere der 'high'-Linie waren im Alter von 8 bis Wochen ca. um 6 bis 11% schwerer. Die realisierte Intra-Familien-Heritabilit?t variierte zwischen den Wiederholungen zwischen 0.16 und 0.27, woraus sich eine mittlerer Heritabilit?tskoeffizient von h(2) = 0.35±0.05 für die Massenselektion ergab. M?use der 'low'-Linie hatten mit 10 Wochen 2.4% (P > 0.05) und mit 17 Wochen ca. 7% (P < 0.05%) mehr Fett. Mit Unterschieden im Wachstum lassen sich weniger als 5% der Linienunterschiede in der Futteraufnahme erkl?ren. Der h?here Erhaltungsbedarf, der aus einer h?heren fett-freien K?rpermasse in der 'high'-Linie resultiert, k?nnte weitere 5% erkl?ren. Tiere der 'high'-Linie verstreuten deutlich (P < 0.05) mehr Futter, worauf sich 23% der Divergenz in der scheinbaren Futteraufnahme zurückführen lie?en. Die Aktiv?t des braunen Fettgewebes, die lokomotorische Aktivit?t und die fütterungsbedingte Wàrmeproduktion sind scheinbar unver?ndert.     

Variation in the colour of broiler breast fillets in the UK

1. The normal range in colour of broiler breast muscle was assessed using an objective (instrumental) measure of colour in portioned breast fillets at a commercial processing plant. In addition, the relationship between colour and ultimate muscle pH (pH(ult)) was also examined. 2. Considerable variation in colour was evident although minimal inter-flock variation was found. The exceptions were 2 free range flocks which produced breast fillets significantly lighter and less red. 3. Extremes of colour are likely to be discriminated against at the point of purchase. 4. A clear relationship between pH(ult) and L* values was found which provides more evidence for the existence of a PSE like condition in broiler breast meat.