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1.
温度是影响蛋鸡生产性能的重要环境因素之一，如何通过营养调控技术，减轻热应激对蛋鸡的负面影响。此文从营养物质如：蛋白质、氨基酸、能量、维生素、矿物质；非营养物质：添加中草药、酸化剂等对蛋鸡热应激的营养调控技术，阐述近几年来，营养调控关键技术在蛋鸡热应激中的应用情况。  相似文献   

2.
蛋鸡的最适气温是20－27℃。如果气温超过等热范围的上限临界温度，蛋鸡会出现热应激，产蛋率下降，蛋重变轻，蛋壳变薄，破蛋率上升。我国南方夏季常出现高温天气，使蛋鸡出现明显效应激。本场每年4月中旬至10月下旬常出现高温，因此，研究如何抓好蛋鸡热应激尤为重要。1．热应自对蛋鸡的影响：1．1行为：当环境气温超过上限时，鸡体散热出现困难，体温上升。为及时散发热量，蛋鸡会减少运动，常呈蹲伏状，或将翅膀张开悬挂于身体两侧站着，以此扩大体表面积，增加散热。1．2呼吸：蛋鸡热应激时，呼吸加快，成年鸡正常呼吸是20次／分钟，当…  相似文献   

3.
为探讨中药冲剂抗蛋鸡热应激的药效学特征,按0.6 g/(只·d)剂量经口给予热应激蛋鸡中药冲剂,考察其对蛋鸡生产性能及血液生化指标的影响。结果表明,中药冲剂抗蛋鸡热应激效果良好,平均产蛋率比对照组提高10.08%(P0.01),饲料报酬提高26%(P0.01),并能调节热应激蛋鸡血液p H值、血浆钙含量、血浆皮质醇含量至正常水平。  相似文献   

4.
薄荷精油与茶多酚配伍对蛋鸡抗热应激的影响   总被引：1，自引：0，他引：1  
为了比较薄荷精油与茶多酚配伍对蛋鸡抗热应激的影响效果,试验设计2个组,Ⅰ组在鸡饲料中加入薄荷精油与茶多酚作为试验组,Ⅱ组在鸡饲料中不加任何添加剂作为对照组,分别饲喂蛋鸡,然后检测其在热应激状态下对蛋鸡生产性能的影响。结果表明:在热应激条件下,与Ⅱ组比较,Ⅰ组能明显提高蛋鸡的产蛋率、蛋重、采食量、饲料报酬、蛋壳厚度、蛋壳强度;降低软破蛋率、死淘率;增加蛋鸡的净收入。说明薄荷精油与茶多酚配伍可以缓解蛋鸡的热应激现象。  相似文献   

5.
维生素C对应激蛋鸡血液生化指标的影响   总被引：1，自引：0，他引：1  
研究热应激和免疫接种应激下，添加不同剂量维生素C（VC）对蛋鸡肌酸磷酸激酶和血糖的影响。日粮中VC添加浓度为0、200、400和1200mg／kg，环境温度为32℃，接种疫苗为新城疫疫苗（NDV）或水（NNDV），试验期28d。试验结果表明，添加VC可降低热应激和免疫应激蛋鸡的肌酸磷酸激酶活性和血糖浓度。VC抗应激效果与其添加量密切相关，400mg／kgVC抗应激效果最好。建议在应激蛋鸡日粮中添加适量VC。  相似文献   

6.
为探讨消暑促情散缓解热应激对内脏器官的影响,将60只成年昆明雌鼠随机分成3组,室温对照组(25℃,基础日粮)、热应激对照组(33℃,基础日粮)和中药组(33℃,基础日粮+1%消暑促情散)。试验期间测定小鼠各项生长指标。30 d后脱颈处死,称量每只小鼠体重以及肝、脾、肺、肾的重量,而后将组织放入波恩氏液中固定,HE染色并观察内脏组织结构变化。结果表明,中药组的增重率和生长率分别为80.23%和1.96%,均显著高于热应激对照组(P0.05);中药组的料肉比为27.83,低于热应激对照组;与热应激对照组相比,中药组的小鼠内脏指数均有所升高,其中肾脏指数显著升高(P0.05),脾脏以及肺脏指数极显著升高(P0.01);通过切片可以看出,热应激对照组肝细胞出现脂肪变性,细胞核浓染以及裂解消失,脾脏炎性细胞明显增多,肺脏组织中肺泡收缩,且有大量炎性细胞浸润,肾脏有明显出血,而中药组有显著改善。说明消暑促情散能够明显缓解热应激造成小鼠生长不良及内脏的损伤。  相似文献   

7.
热应激是指动物机体对热应激源的非特异性防御应答的生理反应，其实质是指环境温度超过等热区中上限临界温度所致的非特异性反应的总和。随着现代蛋鸡生产的日趋规模化、集约化、工厂化及全球性气候变暖，热应激对蛋鸡的影响亦越来越大，严重影响了生产，降低了经济效益。本文就蛋鸡夏季热应激的综合调控措施予以论述，谨供业内同仁参考：  相似文献   

8.
选37周龄罗曼蛋鸡288只,在热应激(平均舍温29.5℃,最高舍温35.2℃)环境下,研究了日粮中添加不同剂量磷脂VC对蛋鸡生产性能的影响。结果表明,与对照组相比,添加300mg/kg的磷脂VC组的采食量提高了6%(P<0.01)@产蛋数和产蛋率分别提高3.6%和3.2%(P<0.05),破蛋率、死亡率和失重率降低。100mg/kg的磷脂VC组可改善蛋鸡生产性能的各项指标但效果不显著。表明日粮中添加300mg/kg磷脂VC能明显提高热应激蛋鸡的采食量和产蛋率,改善蛋鸡的生产性能。  相似文献   

9.
将处于热应激条件下的192只35周龄新罗曼褐壳蛋鸡随机分为6组，分别饲喂不添加铬的玉米-豆粕型基础饲粮和添加作为铬源的葡萄糖耐量因子(GTF)10、20、30、40、50mg／kg的试验饲粮。52d后取血清测血糖浓度，取胰腺制作切片观察组织结构。结果：试验组亮胰岛、暗胰岛体积均增大，细胞排列紧密，结构完好，以30、40mg／kg组变化最为明显；试验组血糖浓度均低于对照组，以30mg／kg组最低；对照组胰岛体积变小，细胞结构模糊．亮胰岛的B细胞出现破损、萎缩、变性、解体及裸核等现象。结果表明。热应激条件下蛋鸡胰岛细胞出现明显病变，补铬能够缓解热应激效应，显著改善胰岛细胞的结构和功能。  相似文献   

10.
比较复方中药和复合西药对热应激蛋鸡生产性能的影响.采用复方中药添加剂和复合西药添加剂对热应激海兰褐蛋鸡生产性能的影响进行对比试验,并对其产蛋率、蛋质量、破蛋率、料蛋比、蛋形指数、蛋壳厚度、蛋壳强度和哈氏单位等指标进行评价分析.结果表明:热应激条件下添加中药抗应激添加剂组和西药抗应激添加剂组的生产性能均明显高于对照组,而中药组和西药组间差异不显著.可以用复方中药代替西药用于蛋鸡抗热应激,而且中草药具有不良反应小、残留低和来源广泛等优点,符合无公害产品生产要求.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

14.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

15.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

16.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

17.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

18.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

19.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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