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91.
The present paper reports the prevalence of coccidiosis in industrial broiler chickens in Faisalabad, Punjab, Pakistan to determine the occurrence of different species of Eimeria in the area and to assess their correlation with the environmental conditions including temperature, humidity and rainfall. The study was conducted from January 2009 to December 2010. Examination of chicken guts revealed 43.89% (n = 3,283/7,480) prevalence of coccidiosis. The highest prevalence (27.04%) was recorded of Eimeria tenella followed by Eimeria maxima (22.42%), Eimeria acervulina (19.89%) and Eimeria necatrix (4.02%). The prevalence of disease was significantly higher (P < 0.05) in autumn (60.02 ± 4.38) followed by summer (47.42 ± 2.92), spring (36.92 ± 2.27) and winter (29.89 ± 3.43). Likewise, prevalence of different species of Eimeria also varied (P < 0.05) in different seasons of the year except that of E. necatrix. A strong correlation (P < 0.05) of environmental conditions with the overall and species-wise prevalence of coccidiosis was recorded except E. necatrix.  相似文献   
92.
本研究选择‘东魁’杨梅为试验材料,以露地栽培为对照,研究大棚设施促早栽培对‘东魁’杨梅的物候期、产量、品质、效益的影响效应。经过3年的试验,通过对‘东魁’杨梅物候期的记载,产量、效益的统计,单果质量、可溶性固形物、总糖、总酸、钾含量、Vc含量等质量指标的检测,综合分析结果表明,东魁杨梅大棚栽培促早、提质、增效效果显著。本研究对优化和推广杨梅大棚促早栽培技术具有重要意义,对山区农民增收提供示范案例。  相似文献   
93.
卵清蛋白因其良好的功能性而作为食品配料被广泛应用于食品工业.本文采用响应面法对影响卵清蛋白凝胶质构特点的外在因素进行研究.对不同温度(70.0-90.0℃)、pH值(5.0~7.0)、NaCl浓度(0.02~0.08 mmol/L)组合条件下的凝胶质构特点进行测定.结果最大的硬度和弹性出现在90.0℃,pH7.0,0.08 mmol/L,而最大的黏性出现在81.7℃,pH6.4,0.08 mmol/L.通过试验研究表明温度对于卵清蛋白凝胶的硬度、黏性、弹性都有显著的影响,NaCl浓度对黏性和弹性有影响,而pH值仅对硬度有影响.只有综合考虑各种外部因素,才能使卵清蛋白质构特点达到理想的效果.  相似文献   
94.

Purpose  

To determine trends in calving ages and calving interval as measures of reproductive performance in Iranian Holsteins in Fars province, southern Iran during 2000–2005.  相似文献   
95.
1. A study was designed to investigate the comparative effect of supplementary vitamin E, vitamin C, probiotics and dietary crude protein concentration on semen traits and seminal plasma biochemical parameters in male broiler breeders after Zn-induced moulting.

2. A total of 180 male broiler breeders were induced to moult at 65 weeks of age by mixing ZnO in diet at the rate 3000?mg/kg of feed. After moulting, the males were divided into six groups that were given feed supplemented with: vitamin C (500?IU/kg), vitamin E (100?IU/kg), protein (140?g CP/kg), probiotics (50?mg/kg) and the combination of these components, while one group was kept as a control. Semen samples were collected weekly and semen volume, spermatozoa concentration, motility and dead spermatozoa percentage were determined. Seminal plasma was separated to determine the concentration of total antioxidant capacity (TAC), homocysteine, paraoxonase (PON1), arylesterase, ceruloplasmin, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities.

3. Semen volume was significantly higher in the vitamin E and C groups compared to the control. Spermatozoa motility was higher in the vitamin E group and dead spermatozoa percentage was significantly lower in the vitamin C group compared with the control group.

4. Seminal plasma TAC was higher in the vitamin E group, homocysteine was lower in the vitamin C and E groups. PON1 was higher in the combination group. Arylesterase increased significantly in the vitamin C and combination groups over time. Seminal plasma AST was significantly lower in the vitamin C and E supplemented groups whereas ALT decreased significantly only in the vitamin E group compared with the control. Higher concentrations of ceruloplasmin were observed in the combination group compared with the other treatments.

5. It was concluded that additional vitamin E and C or their combination was the most potent nutrient treatment for improving the semen traits and seminal plasma biochemical characteristics in male broiler breeders after Zn-induced moulting.  相似文献   
96.
张宾  郭付友 《农业工程》2017,7(4):164-165
针对现有提升器存在的主要问题,分析故障原因,从提升器功能提升、分配器改进设计和油缸结构优化等方面提出新一代提升器改进设计思路。   相似文献   
97.
Several disease indices (DI) have been proposed to assess the severity of phoma stem canker at late growth stages. The DI commonly used in France (called G2 DI) consists of integrating the distribution of the proportions of plants observed within six canker severity classes into a single index. This index uses arbitrarily chosen coefficients associated to each class of canker severity. A given value of this DI can therefore be obtained with different distributions among the canker severity classes. Consequently, it is important to assess to what extent the G2 DI is representative of the distribution of plants in canker severity classes. We show in this study that the G2 DI is a good indicator of the distribution of the observed canker severities, using a dataset from different years, sites and cultivars; this illustrates the robustness of the G2 DI.  相似文献   
98.
In this study salt-free dyeing cotton fabric was achieved by grafting thiourea to cotton fibers, where the thiourea grafted cotton fabric (TUGCF) was prepared by epoxidizing cotton fibers with epichlorohydrin in water and subsequently grafting in aqueous solution of thiourea. Fourier transform infrared spectra (FTIR) and XPS of the TUGCF indicated that a great amount of epoxy groups from the epoxidized cotton fibers reacted with amino groups from thiourea. The TUGCF fabric prepared at the optimum condition and subsequently dyed with reactive dyes in the absence of salt displayed significantly enhanced color strength, showing better dyeing properties when compared with the untreated cotton fabric dyed with conventional methods, in terms of washing fastness, rubbing fastness, and levelness. It was found that the dyeing performance of Reactive Red B-3BF followed a Langmuir-type adsorption curve when used to salt-free dye the TUGCF.  相似文献   
99.
为确定捕捞转场后造成台湾泥鳅(Paramisgurnus dabryanus ssp.Taiwan)死亡的病原,本试验对台湾泥鳅进行病理解剖、病原分离。对分离菌进行形态学观察、生理生化特性测定及16S rDNA基因测序鉴定,并进行人工感染试验、药敏试验。结果显示,从泥鳅肝脏、脾脏、肾脏及肠道组织中分离到形态一致的优势菌株,经纯化保存,命名为XJC。菌株XJC葡萄糖发酵、D-葡萄糖、鸟氨酸、苯丙氨酸及尿素利用阳性,其他所测生化指标均为阴性,与摩氏摩根菌(Morganella morganii)一致;16S rDNA基因序列与摩氏摩根菌相似性达99.6%,被鉴定为摩氏摩根菌。感染试验结果表明,菌株XJC对台湾泥鳅具有致病性,被感染的泥鳅出现了肠道充血典型病理变化。从发病泥鳅体内分离到与菌株XJC一致的菌株,可以判定菌株XJC是泥鳅病原菌。药敏试验结果表明,菌株XJC对氨基糖苷类、喹诺酮类及第三代头孢类药物表现出敏感,对四环素、青霉素、红霉素、多肽类、呋喃唑酮、洁霉素及第一、第二代头孢类药物均等表现耐药,生产中可选用氨基糖苷类、喹诺酮类药物进行摩氏摩根菌疾病的防治。本试验结果可为台湾泥鳅摩氏摩根菌病诊断和防治提供参考。  相似文献   
100.
低档绿茶在养殖业中的开发利用   总被引:1,自引:0,他引:1  
我国绿茶资源丰富,低档绿茶作为一种良好的绿色饲料添加剂在养殖业中具有广阔的应用前景。低档绿茶含有大量的茶多酚,对动物而言,具有抗病毒、提高肌体免疫力、降血脂等功用。  相似文献   
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