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SUMMARY Twenty-five Thoroughbred (TB) and 25 Standardbred (SB) stables were visited to determine their feeding practices. The ingredients of the main feed of the day for a mature gelding of average size in full training were weighed at each stable. Nutrient content of diets was calculated using published data for the individual ingredients. Results are expressed as mean±sd. The estimated body weight of TB horses was 493±34 kg and 437±32 kg for SB horses. There was considerable variation in diet composition and nutrient intake between stables. The TB trainers fed 11.0±2.4 kg and SB trainers 11.8±2.5 kg per day. The concentrate component of the diet weighed 7.8±1.6 and 7.7±2.3 kg for TB and SB stables, respectively, and the roughage component for TB horses 3.3±1.4 and SB horses 4.1±1.4 kg per day. The digestible energy intake of horses at TB stables was 129±29 MJ per day and at SB stables 132±31 MJ per day. Crude protein intake of TB horses was 1452±363 g and SB horses 1442±338 g per day. There were differences in some feeding practices at TB and SB stables. Standardbred trainers fed more roughage than TB trainers. Standardbred trainers fed chaffed lucerne (alfalfa) and cereal hays as the major roughage, whereas TB trainers fed more hay. The major hay type fed by TB trainers was lucerne, whereas many SB trainers preferred clover hay. Both trainers fed oats as the major grain, but TB trainers fed slightly more maize (corn) than SB trainers. The SB trainers fed barley as part of the concentrate component of the diet, whereas TB trainers usually fed boiled barley and linseed oil in winter only. Although many trainers used vitamin and mineral supplements, this appeared unnecessary in many Instances, especially with respect to Iron. Calcium and NaCI supplementation was necessary for some diets. We concluded that while there was a wide range in feed intake and diet composition for both TB and SB horses, average nutrient intakes were similar to National Research Council (1989) recommendations for horses performing intense work.  相似文献   
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In this study, we evaluated the effects of including cassava wastewater in the diet on the feeding behavior of feedlot lambs in 35 male uncastrated Santa Inês × Dorper crossbred lambs at an approximate age of 3 months, with an average live weight of 20.0?±?3.4 kg. Diets were formulated with hay of cassava shoots (roughage) and a concentrate based on corn and soybean, with a roughage:concentrate ratio of 50:50, plus inclusion of cassava wastewater at the levels of 0, 12, 24, 36, or 48 g/kg of the total diet. Feeding behavior was evaluated between the 46th and 52nd days of the experiment. Increasing cassava wastewater levels in the diet reduced (P?<?0.05) the intakes (kg/day) of dry matter and neutral detergent fiber as well as the efficiency of rumination (g/cud and g/h) of dry matter and neutral detergent fiber. The other behavioral parameters were not affected by wastewater inclusion in the diet. Therefore, the inclusion of up to 48 g/kg of cassava wastewater on fresh matter of diets is not recommended for feedlot lambs.  相似文献   
4.
Rotaviruses (RV) have a high prevalence in piggeries worldwide and are one of the major pathogens causing severe diarrhoea in young pigs. RV species A, B, and C have been linked to piglet diarrhoea in Australian pig herds, but their genetic diversity has not been studied in detail. Based on sequencing of the structural viral protein 7 (VP7) RVA G genotypes G3, G4 and G5, and RVC types G1, G3, G5, and G6 have been identified in Australian piggeries in previous studies. Although occurrence of RVB was reported in Australia in 1988, no further genetic analysis has been conducted. To improve health management decisions in Australian pig herds, more information on RV prevalence and genetic diversity is needed. Here, 243 enteric samples collected from 20 pig farms within Eastern Australia were analysed for the presence of RV in different age groups using a novel PCR-based multiplex assay (Pork MultiPath™ enteric panel). RVA, RVB, and RVC were detected in 10, 14, and 14 farms, respectively. Further sequencing of VP7 in selected RV-positive samples revealed G genotypes G2, G5, G9 (RVA), G6, G8, G14, G16, G20 (RVB), and G1, G3, G5, G6 (RVC) present. RVA was only detected in young (<10 weeks old) pigs whereas RVB and RVC were also detected in older animals (>11 weeks old). Interestingly, RVB and RVC G-type occurrence differed between age groups. In conclusion, this study provides new insights on the prevalence and diversity of different RV species in pig herds of Eastern Australia whilst demonstrating the ability of the Pork MultiPath™ technology to accurately differentiate between these RV species.  相似文献   
5.
This study compared the feed preference and growth response of Litopenaeus vannamei to chemoattractants. A diet with 3% fishmeal was supplemented with either 3% salmon meal (POS), 3% soy protein concentrate (NEG), 3% krill meal (KRM), 3% squid meal (SQM), 3% shrimp head meal (SHM), 3% shrimp meal (SM), 3% squid liver meal (SLM), or 5% liquid sardine hydrolysate (SAH). Shrimp with a body weight (BW) of 0.99 ± 0.08 g were stocked at 100 animals/m2 in 56 tanks of 1 m3 and fed 10 times daily for 74 days. Feed preference was evaluated by feeding shrimp of 10.87 ± 1.82 g in excess twice a day for 10 days in two separate feeding trays allocated in 50 tanks of 0.5 m3. Survival reached 93.3 ± 5.80% and was unaffected by supplementation. Final BW was the highest for shrimp fed the KRM‐supplemented diet (11.97 ± 0.93 g), followed by POS (11.11 ± 0.77 g) and SQM (11.01 ± 1.17 g). Diets SHM, SM, SLM, and NEG showed a lower shrimp BW than POS, but were not statistically different among them. Shrimp fed the SAH diet achieved the lowest BW (10.06 ± 1.02 g). The highest gained yield was obtained with diets KRM and POS. No statistical difference was observed in shrimp yield among other diets. The lowest feed conversion ratio (FCR) was achieved with shrimp fed KRM (1.31 ± 0.05) when compared to diets SHM (1.47 ± 0.05), SAH (1.47 ± 0.07), and SLM (1.45 ± 0.17). Two‐by‐two comparisons indicated that shrimp preferred SHM and KRM, except when these were compared to SQM and SLM. No difference in feed preference was found between diets with SQM and SLM. SAH was the least preferred raw material in all comparisons. Results indicated that KRM acts as a powerful feeding effector and growth enhancer in fishmeal‐challenged diets for whiteleg shrimp. A dietary supplementation with 3% KRM is more effective than the same dose of any other chemoattractant evaluated.  相似文献   
6.
Bovine respiratory disease (BRD) exerts a major impact on the beef cattle industry nationally and worldwide, with a range of aetiological factors impacting its pathogenesis. Previous research has focussed on an increasing number of bacteria and viruses that have been shown to play a role in eliciting disease. Recently, additional agents have been emerging as potential contributors to BRD, including the opportunistic pathogen Ureaplasma diversum. To determine if U. diversum was present in Australian feedlot cattle and if that presence was linked to BRD, nasal swabs were collected from a cohort of 34 hospital pen animals and compared to 216 apparently healthy animals sampled contemporaneously at feedlot induction and again after 14 days on feed at an Australian feedlot. All samples were subjected to a de novo polymerase chain reaction (PCR) assay targeting U. diversum in combination with other BRD agents. U. diversum was detected at a low prevalence in cattle at induction (Day 0: 6.9%, Day 14: 9.7%), but in a significantly greater proportion of cattle sampled from the hospital pen (58.8%). When considering the presence of other BRD-associated agents, co-detection of U. diversum and Mycoplasma bovis was most common in hospital pen animals receiving treatment for BRD. These findings suggest that U. diversum may be an opportunistic pathogen involved in the aetiology of BRD in Australian feedlot cattle, in combination with other agents, with further studies are warranted to identify if a causal relationship exists.  相似文献   
7.
The objective was to evaluate the effect of concentrate supplementation using by-products of the Amazonian industry on milk production, milk composition, and milk fatty acid profile of dairy buffaloes. Twelve lactating buffaloes (544.5 ± 35.6 kg, 6.4 ± 2.2 years old, 59 ± 6 days in milk) were allotted in a pasture of Mombaça grass and managed under rotational grazing (4 days occupancy/28 days rest). A 3 × 3 Latin square was adopted, and each animal alternately received three supplementary treatments based on corn bran + soybean meal or cupuaçu cake or murumuru cake for 21 days per treatment. Murumuru cake increased the levels of lauric acid and myristic acid in the milk (p < 0.05). Murumuru cake reduced the unsaturated fatty acid contents in the milk compared with animals fed control diet or cupuaçu cake (24.27% vs. 25.24% vs. 25.08%). The n-6/n-3 ratio was 2.6, 1.97, and 2.0 in the control, cupuaçu, and murumuru groups, respectively. Based on this parameter, cakes made from cupuaçu as well as murumuru could be considered to be adequate for inclusion in dairy water buffalo feed. However, the murumuru cake addition requires some caution because its use induces the secretion of higher levels of lauric and myristic fatty acids that are related to human cardiovascular disease.  相似文献   
8.
This study compared the productive and nutritional parameters of milk from crossbred lactating cows managed on Panicum maximum Jacq. cv. Tanzania and with a diet supplemented with different pressed oilseed cakes. The supplements used were as follows: peanut cake, sunflower cake and palm kernel cake for replacement of soybean meal. Sixteen cows with an average weight of 544 ± 57 kg and producing 8 ± 1.4 L of milk per day were used in this study. The animals were randomly assigned to the treatments according to a Latin square design repeated over time, with four treatments, 16 animals and four experimental periods. Supplementation of the diet with peanut cake, sunflower cake and palm kernel cake compared with soybean meal in the diet of cows did not affect the average daily production or composition of the milk. The palm kernel cake promoted an increase in lauric fatty acids (C12:0) and palmitoleic acids (C16:1) (5.02 and 1.65%, respectively) compared with peanut cake and sunflower cake (4.13 and 4.01%, respectively). The levels of oleic fatty acids (C18:1) were higher for the sunflower cake and palm kernel cake supplements (26.01 and 25.01%, respectively) compared with peanut cake (23.11%). The replacement of soybean meal with sunflower cake and palm kernel cake improved the nutritional quality of the milk, with lower concentrations of saturated fatty acids and higher concentrations of unsaturated fatty acids, without compromising the production or nutritional composition of the milk. © 2015 Japanese Society of Animal Science  相似文献   
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Squamous cell carcinoma (SCC) is an important malignancy in dogs, due to its incidence and clinical presentation, which can be of locally aggressive single or multiple lesions with a metastatic potential. The objective of this investigation was to evaluate SCC response to treatment, anatomopathological and immunohistochemical characteristics, disease-free interval and overall survival time. 54 dogs with histopathologically diagnosed SCC were included in this study. Their mean age was 9.16 years with a range of 1–14 years. Of the 54 animals in the study, 34 (65.4%) had white skin and white fur coats. There was a significant correlation between fur coat colour and the development of tumours in areas of sun exposure (p = .001). Animals with tumours in areas of the body exposed to the sun had longer overall survival time than animals with tumours in areas not associated with sun exposure (p = .001). Surgery combined with electrochemotherapy (ECT) yielded a survival rate 32% higher than using a surgical approach alone (HR = 0.32, p = .038, IC = 0.11–0.94). ECT, with or without surgery, had an objective response rate of 90.9%. Local lymph node and/or distant site metastasis at diagnosis, or at some point during follow-up, occurred in 34.6% (18/52) of animals. Animals with tumours in sun exposed locations had more aggressive histopathological characteristics but had longer overall survival time. This is probably due to individualised therapeutic treatment with both surgery and ECT.  相似文献   
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