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81.
H F Schryver D W Meakim J E Lowe J Williams L V Soderholm H F Hintz 《Equine veterinary journal》1987,19(4):280-287
The effect of level of protein intake on growth and calcium metabolism was studied in 24 foals. Starting at four months old, the foals were fed one of three diets containing all nutrients, with the exception of protein, at levels recommended by the United States National Research Council Subcommittee on Horse Nutrition for a 12 month period. The protein levels in the three diets were 9 per cent (low protein) 14 per cent (NRC recommended level) and 20 per cent (high protein). The foals fed the low protein diet were changed to the high protein diet after 140 days when they were nine months old. There were no significant differences in the rates of growth in weight, height, cannon circumference or in hoof growth and feed utilisation of the horses fed the 14 or the 20 per cent protein diets. However, growth, feed intake and feed utilisation by the foals fed the low (9 per cent) protein diet were significantly depressed. The average daily gains for the first 140 days for the 9, 14 and 20 per cent protein treatment groups were 64, 631 and 687 g in weight, 0.57, 0.83 and 0.87 mm in height and 0.04, 0.13 and 0.14 m in forecannon circumference, respectively. The average daily feed intakes for the 140 day period for the three groups were 2.7, 4.4 and 4.7 kg, respectively. After the change to the high protein diet the foals that had been fed the low protein diet maintained a higher rate of gain in bodyweight, height and cannon circumference, and utilised feed more efficiently than the other two groups throughout the second 140 days of the experiment.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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83.
Abeyesinghe SM McKeegan DE McLeman MA Lowe JC Demmers TG White RP Kranen RW van Bemmel H Lankhaar JA Wathes CM 《British poultry science》2007,48(4):406-423
1. The effects of controlled atmosphere stunning on the behaviour, physiology and carcase and meat quality of broiler chickens were studied experimentally in a pilot scale plant. 2. Gas mixtures tested were: single phase anoxic mixture (90% Ar in air, <2% O(2)); single phase hypercapnic anoxic mixture (60% Ar, 30% CO(2) in air, <2% O(2)); and biphasic hypercapnic hyperoxygenation mixture (anaesthetic phase, 40% CO(2), 30% O(2), 30% N(2); euthanasia phase, 80% CO(2), 5% O(2), 15% N(2)). 3. Anoxic stunning resulted in the least respiratory disruption, mandibulation and motionlessness, but most head shaking, leg paddling and twitching. Loss of posture occurred soonest with hypercapnic anoxia with the earliest and most twitching and wing flapping in individuals and earliest leg paddling. Biphasic birds were most alert, exhibited most respiratory disruption and mandibulation, and had the latest loss of posture and fewest, but longest bouts of wing flapping and least leg paddling and twitching. 4. Significant and sudden bradycardia and arrhythmia were evident with all gas mixtures and were not related solely to anoxia or hypercapnia. Birds stunned by Ar anoxia showed a slightly more gradual decline from baseline rates, compared with hypercapnic mixtures. 5. Few differences were found between gas mixes in terms of carcase and meat quality. Initial bleeding rate was slowest in biphasic-stunned birds, but total blood loss was not affected. Acceleration of post-mortem metabolism in anoxic-stunned birds was not sufficient to allow de-boning within 5 h without the risk of tough meat. 6. On welfare grounds and taking into account other laboratory and field studies, a biphasic method (using consecutive phases of anaesthesia and euthanasia) of controlled atmosphere stunning of broilers is potentially more humane than anoxic or hypercapnic anoxic methods using argon or nitrogen. 相似文献
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86.
NCG Pieri AF Souza JB Casals KCS Roballo CE Ambrósio DS Martins 《Reproduction in domestic animals》2015,50(4):625-631
The precise determination of the embryonic chronology is very important in reproductive biotechnologies, especially in estimating embryonic age. Thus, there is a need for greater knowledge and standardization for determining the chronology of embryonic development and functional morphology. We describe aspects of embryonic development in two domestic carnivores to add knowledge about organ peculiarities and for application in veterinary practice, in prenatal development and in the biotechnology fields. We found that the development of differential characteristics of embryonic organs occurs in the first trimester of pregnancy for both species. Thus, using the combination of the crown‐rump length, macroscopic analysis and optical microscopy, it is possible to predict gestational age more precisely in animals that lack a defined breed and establish an embryonic pattern. 相似文献
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Changes in temperature and silo gas composition during ensiling, storage and feeding-out grass silage 总被引:2,自引:0,他引:2
An experiment is reported in which two bunker silos were filled with about 12 t of ryegrass; one was compacted with a surface pressure of 4·1 kPa and the other was not. Both were instrumented to record temperatures and gas compositions during fermentation and feed-out. Cores of silage (100 mm diameter) were removed from the bunkers and subjected to forced aeration in insulated cylinders. Simple mathematical models were used to simulate CO2 leakage from the silos and the associated loss of dry matter, and temperature changes during the forced aeration of silage cores. The leakage of CO2 from the silos, as shown by the fall in CO2 concentration with time, could be described empirically by an exponential equation and could be simulated with a simple mathematical model. Experimental evidence supported the hypothesis that permeation was the main method of gaseous exchange during fermentation and feed-out, but gas mixing by diffusion and/or convection also occurred within the silos during fermentation. Dry-matter losses by aerobic activity during storage of 120–150 d were conservatively estimated to be about 0·3% and 0·9% for the uncompacted and compacted bunkers respectively. These were considered to be lower than those that could be expected in farm silos, because the sealing was likely to be more thorough. The silages were also more stable, when subject to aeration, than others examined in this laboratory, probably because of high contents of acetic, propionic and butyric acids. Simple mathematical models were of value, but greater sophistication is needed (e.g. multi-compartmental models) to deal comprehensively with the heat and gas flows found in the complex biophysical systems of silage. 相似文献
89.
A spot-on metaflumizone formulation was evaluated to determine its adulticidal efficacy, effect upon egg production, and ovicidal activity when applied to flea infested cats. Eight male and eight female adult domestic shorthair cats were randomly assigned to either serve as non-treated controls or were treated topically with a minimum of 40mg/kg metaflumizone in single spot-on Day 0. On Days -2, 7, 14, 21, 28, 35, 42, 49, and 56, each cat was infested with approximately 100 unfed cat fleas, Ctenocephalides felis felis. On Days 1, 2, and 3, and at 48 and 72h after each post-treatment reinfestation, flea eggs were collected and counted. At approximately 72h after treatment or infestation, each cat was combed to remove and count live fleas. Egg viability was determined by examining hatched eggs after 5 days and adult emergence was determined 28 days after egg collection. Metaflumizone provided >/=99.6% efficacy against adult fleas from Days 3 to 45 following a single application. Following treatment, egg production fell by 51.6% within 24h and 99.2% within 48h. Following subsequent weekly infestations egg production from treated cats was negligible out to Day 38, with >/=99.5% reduction relative to non-treated cats. Where there were eggs to evaluate, metaflumizone treatment did not have any apparent effect on the hatching of eggs or on the development and emergence of adult fleas from the eggs produced by fleas from treated animals. 相似文献
90.
Abstract CASE HISTORY: A 2-year-old Hereford bull was lame for one week before becoming recumbent. CLINICAL AND PATHOLOGICAL FINDINGS: The scrotum and ventral perineal region were cold and blackened caudally. The semimembranosus and semitendinosus muscles were firm on palpation. The bull was subject to euthanasia, and necropsy revealed that the skin and S/C tissues of the caudal half of the scrotum were grey and necrotic. The caudal and distal aspects of the semimembranosus and semitendinosus muscles were grey and necrotic to a depth of approximately 15 cm, and these changes appeared to track along fascial planes. The tissue had an offensive smell, and large amounts of flocculent, watery, brown fluid and some gas were present. Histology of affected muscle and S/C tissues revealed coagulative necrosis, with oedema and large numbers of bacteria that were predominantly Gram-positive rods. Adjacent blood vessels contained thrombi while the epidermis overlying the affected areas appeared diffusely necrotic, suggesting infarction. Culture of the fluid yielded a pure growth of Arcanobacterium spp., which was identified as Arcanobacterium haemolyticum, using an API Coryne biochemical test strip. DIAGNOSIS: Necrotising fasciitis and myositis due to Arcanobacterium haemolyticum. CLINICAL RELEVANCE: Arcanobacterium haemolyticum has not previously been reported as a cause of necrotising fasciitis in any species. Necrotising fasciitis is probably an under-reported condition in cattle due to its clinical similarity to clostridial disease. 相似文献