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51.
To identify the effects of whole crop maize silage (MS) as a substitute for rice straw (RS) on feed intake and milk production of mid-late lactating buffalo and cattle in Tarai, Nepal, eight Murrah and eight Jersey-Hariana were fed the basal diet, RS ( ad libitum ) with concentrate (0.68% of bodyweight [BW] on a dry matter [DM] basis). A 4 × 4 Latin square design experiment was conducted in each animal species with graded levels of MS substitution for RS (0%, T1; 33%, T2; 67%, T3 and 100%, T4). The MS had higher digestibility and total digestible nutrient (TDN) than RS. The DM intake per BW of the both species was highest in T3. The substitution of MS for RS increased the crude protein intake and the TDN intake in the both species. Although the buffalo showed the highest milking performance in T4, the cattle showed no significant differences in their milking performance among the treatments. The substitution of MS for RS improved the feed intake and milk production in the buffalo. On the other hand, the milk yield was not raised in the cattle, though the feed intake was increased by the substitution.  相似文献   
52.
1. An experiment was conducted to determine optimal non-phytate phosphorus (NPP) concentrations for White Leghorn (WL) layers (22–72 weeks) fed diet containing 38 g Ca/kg.

2. Eight diets with graded concentrations (1.5–3.25 g/kg in increments of 0.25 g) of NPP were prepared. Each diet was fed to eight pen replicates containing 88 birds in each. Performance data was evaluated in three different phases (phase I-22–37 weeks, phase II-38–53 weeks and phase III-54–72 weeks). Optimum levels of NPP were determined by fitting a quadratic polynomial (QP) regression model.

3. Egg production (EP) was not affected (P = 0.059) by the concentration of NPP and interaction between NPP and diet phase was non-significant, indicating that the lowest concentration (1.5 g/kg diet) of NPP used in the study was adequate across the three phases. However, EP was influenced by phase (P < 0.001).

4. Optimum concentration of NPP for feed intake (FI) was estimated to be 1.5, 1.71 and 2.40 g/kg diet during phases I, II and III, respectively. FI per egg mass (EM) or feed efficiency (FE) responded quadratically with NPP and also differed significantly between phases. Optimum concentration of NPP for FE during phases I, II and III was 1.5, 2.56 and 2.32 g/kg diet, respectively.

5. Egg weight (EW), EM, shell weight and thickness were not affected by NPP concentration although all of these variables (except shell weight) were influenced by phases.

6. Breaking strength of tibia and Ca contents in tibia ash were not affected by the concentration of NPP, but bone ash and P contents in tibia ash were influenced (P < 0.001) by NPP. Predicted optimal concentrations of NPP for responses for tibia ash at 44 or 72 weeks, tibia ash P at 44 weeks and tibia ash P at 72 weeks were 1.55, 2.63 and 1.5 g/kg diet, respectively.

7. Based on the results, it was concluded that WL layers required 1.5 g, 2.63 g and 2.4 g, respectively/kg diet during phase I, II and III with the calculated daily intake of 137.3, 278.3 and 262 mg NPP/b/d.  相似文献   

53.
Olive oil extraction generates olive cake (OC) that could be used in ruminant feeding. However, the chemical composition of OC is affected by multiple factors, being therefore highly variable. The objective of this study was to analyse the influence of storage time and further processing: crude, exhausted (subjected to a second oil extraction) and cyclone (obtained from a cyclone separator) on nutritive value of OC samples. Twelve samples (six crude and six exhausted) were obtained monthly from the same pond from 1 to 6 storage months, and nine samples (three crude, three exhausted and three cyclone) were obtained monthly from a different pond from 6 to 9 months storage. Chemical composition was analysed, and OC samples were fermented in vitro with sheep rumen fluid. Increasing storage time up to 6 months decreased sugars and total soluble polyphenols content but increased fibre content in OC. Dry matter effective degradability (DMED) decreased linearly (p < 0.001) by 35.9 and 45.5% as storage time augmented from 1 to 6 months for crude and exhausted OC, respectively. Crude OC had lower DMED values than exhausted OC (averaged values 0.255 and 0.294 g/g, respectively). Both potential production and rate of gas production were lower (p ≤ 0.018) in crude compared with exhausted OC, which was attributed to the high fat content of crude OC (≥86 g/kg dry matter). For samples stored longer than 6 months, cyclone had greater (p < 0.05) DMED than crude and exhausted OC (averaged values 0.207, 0.164 and 0.164 g/g, respectively). The results indicate that ruminal degradability of OC is reduced with advancing storage time, but only subtle changes were observed during the first two months. Cyclone showed greater degradability than crude and exhausted OC, but differences between crude and exhausted OC became negligible after five storage months.  相似文献   
54.
Seed dispersal is essential for plant recruitment and the maintenance of biodiversity. Colobine monkeys are primarily folivorous, but they also consume fruits and are often assumed to be seed predators. Although they are known to be epizoochorous seed dispersers, their role as endozoochorous seed dispersers needs reassessment. We examined potential endozoochory in golden snub-nosed monkeys (Rhinopithecus roxellana) at Dalongtan in Shennongjia National Park, central China, by assessing potential germination of ingested seeds (n = 1806, 9 species) from fecal samples. Intact seeds were in almost all fecal samples (ranging from 5–130 seeds), and ingested seeds were from small seeded species (seed width <4.5 mm). The 2 most abundant species were Actinidia arguta (73%) and Rosa caudata (15%). The fruits of A. arguta were unripe when ingested (i.e. effective seed predation) and the ingested seeds did not germinate in the trials. Therefore, ingestion of unripe seeds does not lead to effective seed dispersal. However, germination rates of defecated R. caudata (9%) were greater than control seeds (6% and 0%), demonstrating potential endozoochorous seed dispersal. Thus, colobine monkeys do indeed disperse mainly small-seeded from multi-seeded fruits through potential endozoochory and this process enhances the recruitment of seedlings.  相似文献   
55.
The literature mostly indicates that docking fat-tailed lambs initially reduces growth but that post-weaning growth and feed conversion efficiency then increase. The amount of fat deposited, the total separable lean meat to fat ratio and the meat quality all increase, while the percentage of bone in the carcase either decreases or does not change in the carcases of the docked lambs. Wool growth and characteristics are, in general, not affected and reproductive traits in ewes and lambs are improved by docking. The rectal temperature, respiration rate and pulse rate are decreased following docking. The concentrations of immunoreactive beta-endorphin and cortisol in the plasma and the incidence of foot stamping and restlessness, as indicators of stress, increase after docking. Other constituents of the blood are not significantly altered following docking or by the methods of docking. Docking of fat-tailed sheep using rubber rings at one day of age can be recommended. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
56.
过瘤胃保护胆碱在反刍动物生产上的应用   总被引:1,自引:0,他引:1  
过瘤胃保护胆碱(RPC),可直接添加到日粮中供饲反刍动物,不受瘤胃微生物降解。许多研究证明,RPC能提高反刍动物的生产性能改善其血液、肝脏代谢。本文简要介绍了过瘤胃保护胆碱对反刍动物的影响及作用机理,并对有待于继续研究的问题进行了探讨。  相似文献   
57.
以牛奶为主要原料,添加适量的核桃碎等辅料,利用保加利亚乳杆菌和嗜热链球菌作为发酵剂,确定对核桃发酵乳的制作工艺条件。通过单因素试验和L9(34)正交试验确定最佳核桃酸奶生产工艺流程及工艺参数为:100mL牛奶和10g/100mL白砂糖→灭菌(63℃,30min)→接入5g/100mL发酵剂→35℃恒温发酵12h→加入5g核桃碎→后发酵24h(5~7℃)。利用此工艺制备的核桃酸奶风味独特、营养价值较高,在0~6℃时的货架期可达10d左右。  相似文献   
58.
Impact of MYOD family genes on pork traits in Large White and Landrace pigs   总被引:2,自引:0,他引:2  
Summary Porcine myogenic differentiation genes ( MYOD ) family play a key role in growth and muscle development and are therefore considered as candidate genes for meat production traits. The objective of the study was to investigate the polymorphisms at four loci belonging to the MYOD genes family and analyse their associations with variation in meat production traits in Czech pig breeds. To verify the associations between the polymorphisms and the selected meat traits, altogether 254 pigs, including full- and half-sibs, of Large White and Landrace breeds were tested. The studied meat characteristics were weight of neck, loin, shoulder and ham, lean meat content (LMC), backfat thickness, intramuscular fat (IMF), remission, dry matter content and test daily gain. Statistically significant associations were observed between MYOG gene and fat and neck weight, and between MYF5 gene and IMF and LMC. High significant differences were observed between genotypes AA and AB of MYOD1 in IMF and between genotypes AB and BB of MYF5 in loin weight.  相似文献   
59.
中链脂肪酸(MCFAs)是一类含有6~12个碳原子的饱和脂肪酸.除了作为能源物质之外,MCFAs还具有改善肠道形态结构、提高动物生长性能、防治疾病、调节免疫以及抗菌等功能,因此具有作为抗生素替代品的潜力.本文简述了MCFAs的生物学功能和作用机制,并综述了其在动物生产中的应用研究进展,以期为MCFAs在畜牧业生产中应用...  相似文献   
60.
A nutritional evaluation of an Irish dairy herd indicated gross overfeeding of late lactation cows, over-conditioning of cows at parturition and a high rate of body condition loss in early lactation. Metabolisable-energy based nutritional modelling software was used to guide recommended dietary changes to prevent excessive condition gain in late lactation. Immediately following the implementation of the changes there was an unexpected reduction in performance affecting both milk yield and protein concentration. An investigation into the poor performance revealed underestimation of peak milk yield; over-estimation of maize silage quality; a large difference in the concentrate being fed compared to the concentrate recommended, and failure of the blend of concentrate ingredients to maintain the intended proportions in the in-parlour feeding system. The estimated maximum cumulative effect of these errors was to cause undersupply of energy and protein in the recommended diet of 16% and 3% respectively to cows in early lactation. Use of a net-energy nutritional model would have indicated a requirement for a higher energy supply in this case. This report highlights the challenges in obtaining accurate on-farm data for use in dairy cow nutritional models.  相似文献   
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