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61.
本报告研究了火鸡雏母源抗体的消长规律,并初步探讨了母源抗体对接种疫苗的影响。结果表明,(1)雏鸡母源抗体从1日龄始逐渐升高,6日龄达最高峰(log2 3.47),以后迅速下降,至21日龄全部消失;(2)雏鸡在7日龄、11日龄以及14日龄接种疫苗后的血凝抑制(HI)抗体滴度与不接种疫苗的对照组无明显差别,在19日龄接种疫苗,方能产生HI抗体。因此,火鸡雏首次接种疫苗日龄不宜过早;(3)蛋黄中血凝抑制抗体滴度稍低于其产卵鸡血清中HI抗体滴度,随着孵化时间的延长,蛋黄HI抗体滴度逐渐降低至消失。  相似文献   
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63.
Footpad dermatitis (FPD) and walking ability are both parameters used on poultry welfare audits. One survey was conducted to determine the correlation between FPD severity, gait score (GS), BW, and litter condition on turkeys at market age. A total of 41 commercial tom flocks of 16 to 19 wk of age were evaluated. On each visit, 50 toms were selected, weighed, and evaluated for GS and FPD. Litter score (LS) was also recorded according to moisture content and caking. Data analyses consisted of pairwise correlations and 3 separate multiple linear regression models using FPD, GS, and BW as response variables. Fixed effects included LS, season, FPD, GS, and BW. Based on pairwise correlations, FPD was correlated with LS, BW, GS, and age. Gait score was correlated with LS, BW, and age. Body weight was correlated with LS. With multiple linear regression analysis it was observed that LS and BW were the parameters that were associated the most with FPD severity and GS. As litter condition worsened and BW increased, FPD and GS worsened. Moreover, a seasonal effect was observed on both FPD and GS. Colder seasons, winter and autumn, were associated with increased FPD severity and GS. A negative effect of FPD and GS was observed on BW. In conclusion, FPD and GS are correlated with BW at market age and litter condition is a major factor in FPD development and walking ability in turkeys.  相似文献   
64.
In July 2010, a horse from a rural farm (Farm A) in coastal Northern California was diagnosed with Salmonella Oranienburg infection following referral to a veterinary hospital for colic surgery. Environmental sampling to identify potential sources and persistence of Salmonella on the farm was conducted from August 2010 to March 2011. Salmonella was cultured using standard enrichment and selective plating. Pure colonies were confirmed by biochemical analysis, serotyped and compared by pulsed‐field gel electrophoresis (PFGE) analysis. A total of 204 clinical and environmental samples at Farm A were analysed, and Salmonella spp. was isolated from six of eight (75%) horses, an asymptomatic pet dog, two of seven (28.6%) water samples from horse troughs, nine of 20 (45%) manure storage pile composites, 16 of 71 (22.5%) wild turkey faeces and four of 39 (10.3%) soil samples from the family's edible home garden. Well water and garden vegetable samples and horse faecal samples from a neighbouring ranch were negative. S. Oranienburg with a PFGE pattern indistinguishable from the horse clinical strain was found in all positive sample types on Farm A. The investigation illustrates the potential for widespread dissemination of Salmonella in a farm environment following equine infections. We speculate that a recent surge in the wild turkey population on the property could have introduced S. Oranienburg into the herd, although we cannot rule out the possibility wild turkeys were exposed on the farm or to other potential sources of Salmonella. Findings from the investigation indicated that raw horse manure applied as fertilizer was the most likely source of garden soil contamination. Viable S. Oranienburg persisted in garden soil for an estimated 210 days, which exceeds the 120‐day standard between application and harvest currently required by the National Organic Program. The study underscores the need to educate the public about potential food safety hazards associated with using raw animal manure to fertilize edible home gardens.  相似文献   
65.
Economical, nutritious diets for hybrid striped bass (HSTB) are required for the continued expansion and sustainability of this industry. Turkey meal (TM) is a by‐product of the US turkey industry and is a potentially‐valuable local, alternative protein source for use in aquaculture diets because of its excellent nutritional composition and quality. TM may substitute for more expensive fish meal (FM)‐based diets; however, there are no published data with regard to using this ingredient in sunshine bass diets. Therefore, a 16‐week feeding trial was conducted with juvenile (36 g) sunshine bass (Morone chrysops × Morone saxatilis) to evaluate growth, feed conversion and body composition when fed diets with decreasing levels of FM (300, 200, 100 and 0 g kg?1) and increasing levels of turkey meal (0, 97, 175 and 264 g kg?1). Four practical diets were formulated to contain 400 g kg?1 protein and similar energy levels. Twenty fish were stocked into each of the 12, 1200‐L circular tanks and were fed twice daily ad libitum. At the conclusion of the feeding trial, there were no significant (P > 0.05) differences in final mean weight, percentage weight gain, specific growth rate and feed conversion ratio among treatments, which averaged 363.7 g, 904.3%, 2.02% day?1 and 1.73, respectively. Percentage survival of fish fed diet 4 (0 g kg?1 FM and 264 g kg?1 TM) was significantly (P > 0.05) lower (survival = 88.3%) than fish fed diet 3 (100 g kg?1 FM and 175 g kg?1 TM; survival = 95%), but not different from fish fed diet 1 (survival = 92.5%) and fish fed diet 2 (survival = 93.3%). Fillet weight and amount of abdominal fat were not significantly different among all treatments and averaged 258 and 58 g kg?1, respectively. Fish fed diet 1 (300 g kg?1 FM, 0 g kg?1 TM) and diet 2 (200 g kg?1 FM and 970 g kg?1 TM) had a significantly (P < 0.05) lower hepatosomatic index (2.83 and 3.01, respectively) than fish fed diet 4 (3.33), but not different (P > 0.05) compared to fish fed diet 3 (3.14). Lipid in the fillet of fish fed diet 2 (197 g kg?1) was significantly (P < 0.05) higher than fish fed all other diets; and the percentage lipid in the fillet of fish fed diet 1 (126 g kg?1) was significantly lower than fish fed diets 2 and 4, but not different (P >0.05) compared to fish fed diet 3. Fillet moisture, protein and ash were similar among fish fed all diets and averaged 748, 798 g kg?1 and 51.0 g kg?1 (dry‐matter basis), respectively. The amino acid composition of fillets was similar among all treatments with a few slight significant differences. Results from the present study indicate that tank‐grown sunshine bass can be fed a diet containing 264 g kg?1 TM with 0 g kg?1 FM, compared to diets containing up to 300 g kg?1 FM, without adverse effects on weight gain, growth rate, feed conversion and body composition. Further research should be conducted using lower‐protein diets to determine minimum protein level for tank‐grown sunshine bass.  相似文献   
66.
通过对860只(10批孵化)一日龄雏火鸡进行生殖隆起组织形态观察、摄像绘图,结合解剖观察性器官——睾丸卵巢,发现公雏有6种生殖隆起类型、母雏有5种生殖隆起类型,了解到公母雏火鸡的各种生殖隆起类型所占比例.根据这些生殖隆起类型的特征进行肛门鉴别,雌雄鉴别准确率最高达百分之百.  相似文献   
67.
美国尼古拉斯火鸡产肉性能的测定   总被引:1,自引:0,他引:1  
随机抽样,选择限制饲喂、公母混养、经引种入川后的美国尼古拉斯700系16周龄火鸡,按国家规定的标准方法进行产肉性能测定.测定结果,其半净膛率、全净膛率、胸肌率、腿肌率的平均测定值:公火鸡分别为86.9%、79.8%、24.8%、23.4%;母火鸡分别为86.2%、79.4%、27.4%、20.3%.与所测定的肉杂鸡相比,胸肌率、腿肌率极显著地高于其它家禽,肉质上乘.  相似文献   
68.
经济毛皮动物“白鼻子病”发病原因初析   总被引:3,自引:0,他引:3  
“白鼻子病”在毛皮动物间的广泛流行已经影响到了毛皮动物养殖业的健康快速发展,虽然大多数学者认为是营养代谢病,但是到现在还没有确定该病的具体发病原因。在综合分析了近年基层兽医对“白鼻子病”的治疗体会和国外曾发生过的毛皮动物代谢病的情况后,对它们的发病原因、发病症状、防治方法进行了分析比较,以期为“白鼻子病”的防治提供新的思路。  相似文献   
69.
To evaluate dietary selenium (Se) requirement in turkeys offered a diet supplemented with two levels of vitamin E (VE), 96 newly hatched male BIG 6® chicks (58.4 ± 4.12 g) were divided into eight groups of 12 animals each and fed maize soya diets containing 0.05, 0.10, 0.20 and 0.30 mg Se/kg from sodium selenate in combination either with the natural VE content (approximately 10 IU/kg) or with a VE addition of 50 IU/kg. Animals from all the groups were highly performant and their final body weights (1746 ± 190 g) after 35 days on experiment were not significantly different. According to its dietary supply, Se concentration in the liver and plasma increased dose dependently. Independent of dietary VE, the activities of GPx3 in plasma and of GPx1 in liver and breast muscle increased to a larger extent in turkeys supplemented with 0.10 and 0.20 mg Se/kg in relation to animals with low marginal Se supply (0.05 mg/kg). Supplementation of 0.30 mg Se/kg only slightly increased further selenoprotein activities. 2‐Thiobarbituric acid reactive substances in the liver were strongly reduced by dietary VE, but not by Se. Plasma aspartate aminotransferase (AST) and creatine kinase (CK) activities did not show muscular lesions in none of the groups. Although there were no signs of muscular lesions even in turkeys with marginal Se and moderate VE supply, the activity of selenoproteins in various organs increased up to 0.30 mg Se/kg diet, independent of VE supply. It was concluded that for growing turkeys the Se supply should meet at least a level of 0.20 mg/kg diet as currently recommended by the National Research Council and Gesellschaft für Ernährungsphysiologie. Vitamin E addition confirmed the particular function of the vitamin as a lipid antioxidant and should be taken into consideration when diets with high PUFA concentrations are fed.  相似文献   
70.
Two 28-d experiments were conducted to evaluate the effect of grinding corn or soybean meal (SBM) to various particle sizes on P utilization in turkey poults. Dietary Ca was formulated to be 1.20% in the corn-SBM-based diets of both studies and nonphytate P (NPP) was calculated to be 0.40% in experiment 1 and 0.48% in experiment 2. In experiment 1, corn that had been processed through a roller mill was used or was ground through 3 different screen sizes in a hammer mill to yield 4 corn particle sizes ranging from about 600 to 1,100 μm. Initial (7 d) growth was reduced when the coarsest corn was fed due to lower feed intake. Phosphorus utilization was improved the first 2 wk as corn particle size increased as measured by incidence of rickets, tibia ash, and total P retention. Gizzard weight and phytate P retention were increased at 28 d as corn particle size increased. In experiment 2, corn was ground to approximately 850 μm and commercial SBM (856 μm) was used or ground to 2 finer particle sizes in a hammer mill. Gizzard weight and phytate P retention were increased at 28 d as SBM particle size increased. Other parameters were not affected at least partially due to the higher dietary NPP level fed to prevent severe rickets observed in the first trial. These studies show that young poults can utilize P better from coarser corn and soybean meal, especially when dietary P is low.  相似文献   
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