Ultrasonic, needle, and carcass measurements for predicting chemical composition of lamb carcasses

Three groups (n = 147) of New Zealand mixed breed lambs averaging 170 d of age and 31.7 kg in weight were killed after a diet of pasture to determine whether the total depth of soft tissues over the 12th rib 11 cm from the dorsal midline (GR) could be measured in live lambs with sufficient accuracy to warrant its use as a selection tool for breeding flock replacements. Relationships among live and carcass measurements and carcass chemical composition also were determined. An ultrasonic measurement of GR in the live lambs was a more accurate predictor of carcass GR (r = .87) and percentage carcass fat (r = .80) than was a measurement of GR made with a needle (r = .80 and .67, respectively). Both measurements were sufficiently accurate to permit culling of over-fat lambs from breeding flock replacement prospects. The best single indicator of percentage carcass fat (r = .87) was a shoulder fat measurement, followed closely by carcass GR (r = .85). Both were superior to USDA yield grade for estimating carcass chemical composition in these young, lightweight lambs. These two measurements also were most highly related to percentage carcass protein (r = -.78 and r = -.77, respectively). These results indicate possibilities for improving the method of evaluating the composition of U. S. lamb carcasses.     

The effect of salinomycin on apparent digestibility, indices of rumen fermentation and fattening and slaughter yields of cattle

The influence of salinomycin (0, 15, 30 and 60 mg per animal and day) on apparent digestibility of artificially dried grass was investigated in four experiments with five wether each. Three long term individual feeding experiments (210 to 252 days) with 72 growing bulls were carried out. The influence of various salinomycin levels (100 to 300 mg per animal and day) were investigated on parameters of rumen fermentation as well as fattening and slaughtering results. Salinomycin decreased insignificantly (P greater than 0.05) the apparent digestibility of organic matter (71.0; 70.1; 68.7 and 68.4%) and crude carbohydrates (71.8; 70.3; 69.2 and 68.5% resp.). The digestibility of other nutrients was not influenced. Supplementation of salinomycin reduced molar concentration of acetate (49 to 115) and butyrate (22 to 82) and increased propionate (110 to 199 mmoles per mol) in rumen liquid. Dry matter intake of bulls declined (0.8%, 13.5 and 24.6; 4.7% of experiments 1 to 3) when salinomycin was added. Daily weight gain (6.5 and 1.0%) and feed efficiency (6.8 and 6.3%) of bulls supplemented with salinomycin were improved in experiments 1 and 3. Significant decrease of feed intake of bulls of experiment 2 affected decline of weight gain probably as consequence of high salinomycin levels. Slaughtering results (except experiment 2) and body composition of bulls were not significantly influenced by salinomycin. Under consideration of own results and some references 10 to 20 mg per kg dry matter or 50 to 150 mg salinomycin per fattening bull and day are recommended as optimal level.     

Otoacoustic emission in a dog

A 7-month-old female Poodle was evaluated for a sound continuously emanating from its left ear. The frequency and intensity of the tone was matched by use of a multifrequency audiometer. The frequency and intensity of the sound were 9,594 Hz and 45.5 decibels sound pressure level, respectively. On the bases of normal brain stem auditory-evoked responses and behavioral response to sound, the dog was believed to have normal hearing in both ears. Emission of sound from an ear, referred to as an otoacoustic emission, is a condition that has been reported in human beings and small animals. Successful treatment in human patients with drugs and masking sounds is difficult, and treatment has not been reported in animals. This condition in dogs is not considered life-threatening.     

Udder oedema associated with adrenocortical insufficiency in a herd of Holstein/Friesian cows

The possible involvement of the pituitary-adrenocortical axis with severe pre- and post partum udder oedema was studied in a herd of 60 Holstein/Friesian cows. The prevalence of udder oedema in this herd was about 75 per cent. The animals were fed a diet containing high levels of potassium (average daily potassium intake 410 g per cow). The concentrations of sodium, potassium, chloride and total protein in the plasma of the cows were within their normal ranges. In one animal a very low plasma cortisol concentration (2.30 ng/ml) was accompanied by normal plasma glucose and beta-hydroxybutyrate concentrations. The adrenal responsiveness of two heifers with severe udder oedema was impaired one month after parturition in comparison with 11 normal animals (increases from 3.27 to 38.8 and 23.2 to 37.8 ng cortisol/ml compared with 8.02 +/- 1.19 to 146 +/- 16.7 ng cortisol/ml but returned to normal spontaneously after 175 days. One cow was diagnosed as having primary adrenocortical insufficiency.     

Total and relative deficiency of gut mucosal IgA in German shepherd dogs demonstrated by faecal analysis

The concentration of immunoglobulins in faecal extracts was investigated as a method of assessing the production of immunoglobulins by the gut mucosa of 137 dogs. There were significant correlations between the concentrations in faecal extracts and the concentrations produced in duodenal organ cultures. Seventy-six German shepherd dogs had significantly lower median immunoglobulin A (IgA) concentrations in their faecal extracts than 63 controls of various breeds. Sixteen of the German shepherd dogs had IgA concentrations below the 95 per cent confidence limit of the control population and six had no demonstrable faecal IgA. The faecal concentrations of immunoglobulin G and albumin were significantly higher in the German shepherd dogs than in the controls, but their immunoglobulin M concentrations were similar.     

A novel treatment for dynamic laryngeal collapse associated with poll flexion: the modified checkrein

Reasons for performing the study: Dynamic laryngeal collapse (DLC) associated with poll flexion is a performance limiting dynamic upper airway disorder commonly diagnosed in Coldblooded trotters. An inspiratory obstruction occurs when affected horses are driven with tension on the reins, inducing poll flexion. To date, surgical treatment and conservative management have failed to improve racing performance in affected horses. Objectives: To test the efficacy of an external device, the modified checkrein, in limiting poll flexion, diminishing laryngeal collapse and improving airway mechanics when horses are driven on a treadmill with tension on the reins and test the hypothesis that the modified checkrein will limit poll flexion thereby improving endoscopic appearance of the larynx and reduce airway obstruction in harness racehorses affected with DLC. Methods: Fourteen Norwegian Coldblooded trotter (NCT) racehorses previously diagnosed with DLC associated with poll flexion exercised on a high‐speed treadmill at speeds that resulted in heart rate >200 beats/min. Upper airway videoendoscopy recordings, tracheal pressures and video recordings of the head and neck position were collected while horses exercised with the conventional checkrein on Day 1 and the modified checkrein on Day 2. Results: The modified checkrein successfully limited poll flexion as measured by no change in head position parameters between phases of no rein tension and phases of rein tension. Endoscopic scores were significantly improved (arytenoids cartilage collapse P<0.0001; vocal fold collapse P<0.0001) and tracheal peak inspiratory pressures were significantly less negative (P = 0.0162) when horses were fitted with the modified checkrein compared to the conventional checkrein. Conclusions and potential relevance: The modified checkrein successfully limited poll flexion and also prevented upper airway obstruction in NCT horses affected with DLC associated with poll flexion. The modified checkrein seems promising in offering a method of conservative management in harness racehorses affected with this disorder.     

Transverse and dorso-ventral changes in thoracic dimension during equine locomotion

Changes in shape of the equine thorax during locomotion are not well defined, although it has been shown recently that the transverse hemi-diameter changes its dimension by up to 80 mm on the side of the trailing forelimb during gallop, despite minimal change in thoracic circumference. The aim of this project was to analyse transverse and dorso-ventral changes in shape of the thorax simultaneously, and to determine if leading limb, treadmill slope and speed have an effect on these shape changes. Reflective markers were placed on the horse’s hemi-thorax and movement of the markers was recorded using a motion capture system while the horse trotted and cantered on a treadmill. Treadmill speed and slope, and the lead the horse cantered on were varied to determine the effects these had on transverse hemi-diameter and dorso-ventral diameter.There was a negative correlation between transverse and dorso-ventral changes in thoracic dimension, the strength of which increased with speed on the trailing limb side. On the leading side, the relationship was either weakly negative or positive. The changes in dimension of the hemi-thorax were significantly greater on the trailing side compared to the leading side. Speed had small effects on thoracic shape changes, but inclined exercise caused an increase in transverse hemi-diameter on the trailing side of the thorax. The changes in thoracic shape are unlikely to contribute substantially to ventilation and rib motion is likely to be due to protraction and retraction of the forelimbs. However, it may reflect asynchronous ventilation of lung lobes and partially explain the prevalence of exercise-induced pulmonary haemorrhage.