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文章综述了25-羟基维生素D(325-OH D3)在动物(主要是家禽)营养中的研究进展:①25-OH D3改善肉鸡生长性能,但会受到基础饲粮钙、磷和维生素D(3VD3)水平的影响;②25-OH D3改善肉鸡骨骼质量,降低TD(胫骨软骨发育不良)发病率,但受到肉鸡品系的影响;③25-OH D3增加肉鸡植酸磷回肠末端消化率,但未影响肠道(内源)植酸酶活性;④25-OH D3调节肉鸡肠道形态和免疫机能;⑤25-OH D3改善产蛋鸡产蛋后期蛋壳质量;⑥以家禽骨骼和蛋壳质量为评价指标,25-OH D3生物学活性为VD3的1~2.5倍;⑦以家禽肾脏钙化评价,25-OHD3的毒性约为VD3的5~10倍。 相似文献
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在过去几十年中,由于肉用仔鸡的快速生长,骨骼畸形问题也日益突出。家禽骨骼畸形会降低肉用仔鸡的生产性能,提高家禽死亡率,难以加工并影响胴体品质,给家禽生产厂、加工厂造成巨大经济损失。影响家禽骨骼畸形发生的因素很多,营养因素是其中一个非常重要的因素。研究表明:日粮中的8种维生素、13种矿物元素、6种氨基酸以及日粮能量和蛋白质水平都与家禽骨骼畸形有关。在过去20~30年间,研究主要集中于维生素D、钙、磷、氯、锌、铜、胱氨酸、半胱氨酸、同型半胱氨酸、脂肪酸等营养因素。近5~6年,国内外关于维生素D代谢及其与家禽骨骼畸形之间 相似文献
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一、维生素维生素是家禽维持生命、生长发育、正常生理机能和新陈代谢所必需的一类特殊的低分子有机化合物。当维生素缺乏时,会引起维生素缺乏症,造成禽体物质代谢紊乱、生长停滞以致发生各种疾病,严重时甚至可以引起死亡。引起家禽维生素缺乏的原因主要有:(1)维生素来源不足,饲料中维生素不足或因加工储存不当而造成损失、破坏过多,长期使用抗菌药物使家禽肠道细菌合成维生素受到抑制,家禽对饲料摄取量不足;(2)家禽对维生素的需要量增加,如幼禽、产蛋禽对各种维生素(特别是维生素A、D)的需要量增加,感染性疾病、中毒、高热或处应激状态下… 相似文献
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25-羟D3不同添加水平对罗曼父母代种鸡生产性能的影响 总被引:2,自引:0,他引:2
25-羟基维生素D3是维生素D3的代谢物,它与维生素D3不同,更容易吸收,很少受肠道中脂肪和胆汁存在与否的影响,是维生素D3的一种活性产物。它能有效的降低蛋鸡的破蛋率、腿病发病率,提高鸡的生产性能,种蛋的受精率、孵化率和健雏率。维生素D3彼家禽或动物采食后,需要在肝脏经羟化作用转变为25-羟基维生素D3,25-羟D3经血液运送到肾脏后,在1-α-羟化酶作用下,转变为1,25-二羟基维生素D3,1,25-二羟基维生素D3为维生素D3的活性形式,可调节钙和磷结合蛋白的合成,继而调节钙和磷自小肠的吸收、运送血液钙和磷的浓度. 相似文献
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《养殖与饲料.饲料世界》2005,(3):18-20
维生素D2主要存在于植物性饲料中,如麦角和酵母;而维生素D3则主要由存在于动物的皮肤、血液、神经和脂肪组织中的7脱氢胆固醇在紫外线照射下生成。维生素D2与维生素D3对哺乳动物的活性基本相同;对于包括家禽在内的鸟类,维生素D3的活性远高于D2,前者约为后者的20~40倍;奶牛维生素D2的效价可能只有维生素D3的1/2~1/4。近年来,对活性维生素D的研究有了进一步的认识,逐渐发现活性维生素D除具有经典的钙磷调节作用以外,还参与调节许多细胞的代谢过程,对机体的免疫功能、生殖等方面均有着十分重要的意义。作者就近年来国内外对维生素D在动… 相似文献
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家禽营养代谢病的病因及诊治 总被引:1,自引:0,他引:1
1 家禽营养代谢病的种类
脂溶性维生素A、维生素D、维生素E、维生素K缺乏或代谢障碍病;水溶性维生素B1、维生素B2、泛酸、烟酸、生物素、胆碱、叶酸、维生素B12以及维生素C的缺乏或代谢障碍病。 相似文献
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Mites can be important sources of airborne allergens, especially on farms. Two dust samples from pig farms and three dust samples from poultry farms were investigated for mites. House-dust mites were present in the poultry-dust samples, but not in the pig-dust samples. Furthermore, storage mites and predatory mites also were found in the poultry-dust samples. Specifically, the house-dust mite Dermatophagoides evansi was found in the dust samples from two poultry farms. Subsequently, a dust sample was collected from five other poultry farms. Again, D. evansi was present in dust from these farms. This is the first time that D. evansi is reported in dust from poultry farms in Western Europe outside Norway. If D. evansi cross-reacts with other Dermatophagoides spp., then poultry farmers and their families, but also other professionals working in the poultry industry, such as veterinarians, may be exposed to house-dust mites with potential clinical consequences, both domestic and occupational. 相似文献
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The poultry red mite Dermanyssus gallinae is a major pest and widespread ectoparasite of laying hens and other domestic and wild birds. Under optimal conditions, D. gallinae can complete its lifecycle in less than 10 days, leading to rapid proliferation of populations in poultry systems. This paper focuses on developing a theoretical model framework to describe the population dynamics of D. gallinae. This model is then used to test the efficacy and residual effect of different control options for managing D. gallinae. As well as allowing comparison between treatment options, the model also allows comparison of treatment efficacies to different D. gallinae life stages. Three different means for controlling D. gallinae populations were subjected to the model using computer simulations: mechanical cleaning (killing once at a given time all accessible population stages), sanitary clearance (starving the mite population for a given duration, e.g. between flocks) and acaricide treatment (killing a proportion of nymphs and adults during the persistence of the treatment). Simulations showed that mechanical cleaning and sanitary clearance alone could not eradicate the model D. gallinae population, although these methods did delay population establishment. In contrast, the complete eradication of the model D. gallinae population was achieved by several successive acaricide treatments in close succession, even when a relatively low treatment level was used. 相似文献
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The influence of 'time since last blood meal' on the toxicity of essential oils to the poultry red mite (Dermanyssus gallinae) 总被引:1,自引:1,他引:0
The poultry red mite, Dermanyssus gallinae (De Geer) is a serious ectoparasitic pest of layer hens that can survive for long periods in the poultry house sub-structure without taking a blood meal from its host. The research undertaken in this study found that 'time since last blood meal' had a notable effect on how toxic a selection of plant essential oils were to D. gallinae under laboratory conditions. In general, the essential oils had a greater toxic effect on D. gallinae if mites had been starved of a blood meal for around 3 weeks, than if they had been more recently fed 3-13 days prior to tests. This result was consistent across the four essential oils used (thyme, palmarosa, caraway and juniper leaf). This suggests that plant essential oils may be of use in management schemes for D. gallinae, particularly if used to sanitise houses between flocks, when mites will have been starved. 相似文献
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Infectious bronchitis (IB) is a highly contagious viral disease and is responsible for considerable economic losses in the poultry industry, worldwide. To mitigate the IB-associated losses, multiple vaccines are being applied in the sector with variable successes and thus necessitating the development of a potent vaccine to protect against the IB in the poultry. In the present study, we investigated a bivalent live attenuated vaccine consisting of IB virus (IBV) strain H120 (GI-1 lineage) and D274 (GI-12 lineage) to evaluate its protection against heterologous variant of IBV (GI-23 lineage) in chicken. Protection efficacy was evaluated based on the serology, clinical signs, survival rates, tracheal and kidney histopathology and the viral shedding. Results demonstrated that administering live H120 and D274 (named here Classivar®) vaccine in one day-old and 14 days-old provided 100 % protection. We observed a significant increase in the mean antibody titers, reduced virus shedding, and ameliorated histopathology lesions compared to routinely used vaccination regimes. These results revealed that usage of different IBV vaccines combination can successfully ameliorate the clinical outcome and pathology in vaccinated chicks especially after booster vaccination regime using Classivar®. In conclusions, our data indicate that Classivar® vaccine is safe in chicks and may serve as an effective vaccine against the threat posed by commonly circulating IBV strains in the poultry industry. 相似文献
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Field efficacy of phoxim 50% (ByeMite) against the poultry red mite Dermanyssus gallinae in battery cages stocked with laying hens 总被引:2,自引:0,他引:2
Infestations with the poultry red mite Dermanyssus gallinae represent a major ectoparasite problem in poultry and can affect egg layers worldwide. There is presently a lack of an ectoparasiticide in Europe for poultry which can assure a 0-day withholding period for eggs. In this study, ByeMite (phoxim 50%, Bayer HealthCare, Animal Health Division) was administered to treat a D. gallinae infestation in a poultry house stocked with egg-laying hens kept in a cage system. A layer house was sprayed twice within a 7-day interval using a solution containing 2000 ppm phoxim and a similar layer house was used as an untreated control unit. Specially developed D. gallinae traps made of cardboard were used to assess the mite density in both layer houses during a 49-day period after the treatment. In order to collect mites, the traps were placed on days--1, 2, 6, 9, 13, 20, 34 and 48 and always removed after 24 h. The collected mites were counted and differentiated according to their developmental stage (mite eggs, larvae, nymphs, adults). Three days after the first spray treatment, the efficacy against all mite stages (larvae, nymphs, adults) was 96.1%, and from day 7 post-treatment until the end of the trial (day 49) the efficacy exceeded 99%. In contrast, in the untreated layer house (negative control group) the mite population showed a 400% increase. No treatment-related side effects in chickens were detectable. It is concluded that two administrations of ByeMite within a 7-day interval are highly effective against D. gallinae infestations in a stocked poultry house. 相似文献
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A A Ojeniyi 《Acta veterinaria Scandinavica》1989,30(2):133-139
Eighty per cent of Enterobacteriaceae isolates from battery poultry exhibited drug resistance in a survey among university and commercial poultry flocks. These birds, being a source of human food, may serve as an important reservoir for human pathogenic drug-resistant enteric organisms. Feeds used on University and Commercial poultry farms were found to be inhibitory to standard test organisms--Oxford strain of Staphylococcus aureus and Escherichia coli K 12 J5 NA+ Lac-. Feed additives, which purportedly were mineral and vitamin supplements, were found to be highly laden with antibacterials, a quantitative estimation of which revealed that one of them, termed A & D Crumbles contained as much as 3000 (three thousand) micrograms of antibiotic per g, while another feed additive known as ADVIT contained 130 micrograms of antibiotic per g of the feed supplement. These are routinely added to poultry feeds, a practice which may easily lead to development of drug resistance among enteric pathogens that may, in turn, reach humans and complicate therapy of human bacterial infections. This may be of a considerable public health significance. 相似文献