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1.
为了推动我省蛋鸡业的可持续发展,改变目前落后的养殖方式,促进蛋鸡产业的升级和整体素质提高,实现蛋鸡生产的优质、高产、高效、安全,湖北省畜牧技术推广总站组织编印并推广了“蛋鸡’153’标准化养殖模式”。  相似文献   

2.
The stability of endotoxins was investigated in potential sources (feed-stuff, litter, water, excrements, surface dust) of that air contaminant and in the airborne state. No changes in the endotoxic activity were found in materials with high dry matter (straw, hay, dried faeces) during 84 days. In manure samples stages of increasing and decreasing endotoxic activity were observed. In water a continuous decline of the endotoxic activity was found. However this process was characterised by half-life periods on a weekly scale. Bacterial degradation seems to be responsible for that loss of endotoxic activity.  相似文献   

3.

Dairy calf rearing unit is a management system that is only recently being implemented by some milk producer’s cooperatives in southern Brazil. However, aspects related to the health profile of the heifer calves that arrive in the rearing unit as well as about biosecurity practices and microbiological challenges have not yet been evaluated in this rearing system in a tropical country. Diarrhea is the main and most frequent consequence of enteric infections in newborn calves. This study, through some etiological and epidemiological characteristics of an outbreak of neonatal diarrhea, has the aim to alert to the possibility of pathogenic microorganism spread in a dairy heifer calf rearing unit. The diarrhea outbreak presented some non-regular characteristics observed in bovine coronavirus (BCoV) enteric infections in dairy calves. The spread of infection was extremely rapid (1 week); the attack rate (>?50%) was much higher than that observed in calves subjected to conventional rearing; and the age range (5 to 90 days) of the affected heifer calves was much broader than that often observed in the BCoV diarrhea worldwide. These unusual epidemiological characteristics observed in this BCoV diarrhea outbreak raise awareness of the health threat present in calf rearing units as well as of the easy and rapid viral spread in a population of young animals from different dairy herds and, therefore, with very distinct immunological status.

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4.
薛志成 《蚕学通讯》2005,25(3):38-38,55
蒸笼养蚕又叫笼箱密闭养蚕,是根据小蚕喜高温多湿环境和对二氧化碳抵抗力强的生理特性,结合农村分户养蚕面广、条件差、技术落后、饲养规模小的实际情况实践出的一种简易养蚕方法.与传统方法不同的是将蚕饲养在专用的蒸笼内,给桑后把蒸笼密闭起来,使桑叶长时间保持新鲜,提高蚕的食桑量和消化量,促进蚕良好地生长发育.实践证明,饲养1~3龄蚕能很好地满足蚕生长发育所必需的气象、营养、卫生环境,蚕儿生长快、发育整齐、蚕体健壮、产茧量高、方法简单、省工、省叶、又便于消毒防病,在养蚕分散、饲养规模小的地方尤为适用.现将武胜县蚕业工作者和广大蚕农总结的蒸笼养蚕特点及饲养技术推荐给大家,供参考使用.  相似文献   

5.
牟静  牟润生 《蚕学通讯》2001,21(1):9-10
目前养蚕生产上普遍采用的仍是以普通育为主体的室内养蚕方法 ,要占用大量房屋、蚕具 ,投资大、用工多、大蚕期一个劳力只能养一张蚕 ,成本高、消耗大、效益低、质量差 ,很不适应当前农业规模化、集约经营的形势 ,严重制约了茧丝绸生产的发展。作者经过多年的实践探讨 ,摸索出家蚕全龄室外大棚省力化饲育技术 ,现简述如下 :1 室外塑料大棚的建造1 .1 建造时间 春蚕期 :4月上旬~中旬 ,夏蚕期 6月中旬~下旬 ,秋蚕期 8月上旬~ 9月上旬 ,也可建立一劳永逸的大棚 ,一年内多次使用 ,连用几年。1 .2 建造地点的选择 地势较高 ,土地平坦 ,交…  相似文献   

6.
The species composition of airborne gram-negative bacteria and the relationship between inhalable endotoxin, inhalable dust and airborne bacteria were studied in 4 pig houses. The airborne gram-negative bacterial flora was dominated by Enterobacteriaceae. Within the Enterobacteriaceae the species E. coli and Enterobacter agglomerans were predominant. Significant correlation were found between the concentration of inhalable dust and inhalable endotoxin as well as between the concentration of airborne gram-negative bacteria and inhalable endotoxin. However these correlation were not very strong. With respect to the characterization of the potential hazard of organic dust exposure, measurements of the concentration of airborne dust or airborne bacteria should not be used for the estimation of the concentration of airborne endotoxin.  相似文献   

7.
The potential conflict between reproductive functions and the drive to deposit body protein may impair productive performance in modern gilts of lean genotype. To study the response of the gilt to this conflict, a choice-feeding experiment was carried out to measure the nutrient intake selected by breeding gilts and responses in reproductive and lactation performance. Using a 2 × 2 factorial design, gilts of two different genotypes (24 of NPD 402, expected higher body protein/lipid ratio (L) or 24 of Camborough 23, expected lower body protein/lipid ratio, (F)) were either choice-fed (C) by offering both a low (120 g crude protein (CP)/kg) and a high protein (218 g CP/kg) feed during rearing and pregnancy or fed conventionally (R) single feeds, ad libitum during rearing and restricted during pregnancy. Choice-fed gilts selected mainly the low protein feed (0.92 of total feed intake) regardless of genotype and had lower protein intakes than R gilts prior to puberty. However, in pregnancy, due to higher feed intakes, C gilts had higher dietary protein and energy intakes than R gilts. C gilts were heavier, and had greater back-fat and eye muscle depth at farrowing than R gilts, but had smaller litter sizes (P < 0.01). During lactation, dietary treatments were reallocated so that gilts received either a low (LE, maintenance + 45 MJ/day) or a high (HE, maintenance + 67 MJ/day) digestible energy intake. Litter size was standardised within 2 days of farrowing. LE gilts had greater decreases in weight and back-fat and eye-muscle depth during lactation than HE gilts, but dietary lactation treatment had no effect on litter performance. The choice-feeding regime which resulted in heavier gilts with greater back-fat and eye-muscle depth at farrowing did not produce any advantage in terms of partitioning of nutrients towards milk production, as indicated by litter performance, irrespective of gilt genotype. F gilts had greater piglet growth rates than L gilts and also had a higher milk protein concentration. A greater number of L than F gilts failed to complete the experiment for health reasons. Treatment effects on glucose tolerance at day 13 of lactation were not significant. Choice-feeding was therefore not found to be suitable for determining nutrient requirements of modern lean-genotype gilts which would improve reproductive performance.  相似文献   

8.
We investigated the associations between Campylobacter colonisation and management practices and farm characteristics in 603 housed broiler batches originating from 137 farms in Great Britain. All study batches were the initial batch slaughtered from the selected house on enrolled farms. Between 1 and 15 batches were sampled from each farm throughout the study. A total of 34.2% of the batches was Campylobacter positive and multivariable multilevel logistic regression revealed that the risk of Campylobacter colonisation was highest in July (OR = 3.4, CI95%:1.8; 6.4), August (OR = 3.4, CI95%:1.9; 6.2) and September (OR = 3.7, CI95%:1.9; 7.1). Cattle on or adjacent to the farm increased the risk (OR = 1.7, CI95%:1.1; 2.7), whereas chlorinated drinking water reduced it (OR = 0.5, CI95%:0.2; 0.9). If the first removed batch from the previous flock in the house had been Campylobacter positive, the first batch of the following flock was also more likely to be colonised (OR = 3.2, CI95%:2.1; 4.9). This association was more likely due to a persistent risk practice or source of Campylobacter on the farm than a direct carry-over from previous flock.  相似文献   

9.
叠式蚕框育蚕,操作方便,程序简化,蚕房、蚕框消毒方便,节省用工,降低生产成本,提高效益,便于集中管理,提高共育室及设备的利用率,有利于提高小蚕共育质量,是取代传统蚕框育蚕的良好的育蚕方式。  相似文献   

10.
First-fortnight incidence (FFI) is a modelling parameter that can be used to predict both the prevalence and duration of a foot-and-mouth disease (FMD) epidemic at regional and national levels. With an indication of how long an epidemic may last by the end of week two, it becomes possible to estimate whether vaccination would be economically viable from the start of an epidemic. Where FFI indicates that an epidemic is unlikely to last for as long as an export ban on agricultural produce, it may be inappropriate to implement a policy of 'vaccination to live'. Alternatively where FFI indicates that an epidemic will equal or exceed the ban length, then the benefits of vaccination should be considered at an early stage, during or after the first fortnight. Since blanket vaccination of the national or regional herds and flocks would be both costly and heighten the risk of producing carrier animals, targetting vaccination through risk assessment becomes useful.  相似文献   

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The immunity state after vaccination against Marek's disease (MD) was studied in three multiplier flocks of laying fowl (MFL), five multiplier flocks of broiler fowl (MFB), and one commercial layer flock (CLF). The occurrence and average titres of post-vaccination viraemia in the selected sets of chickens from these flocks, examined at the age of three or twenty weeks, were used as the immunity criterion. The development of post-vaccination viraemia, following the administration of the MARVAK vaccine at the doses of 100 and 1000 PFU per bird in the HX-SL and Shaver layer hybrids, was examined under laboratory conditions at the same time. In the group of birds examined in the third week of age and coming from the MFL vaccinated with the recommended MARVAK vaccine (dose (100 PFU per bird), 64.3% of the chicks were viraemic, the average viraemia titre being 12 PFU/10(7) leucocytes. After the administration of a four-fold vaccine dose, 57.1% of the chicks were viraemic, the average titre being 3.2 PFU/10(7) leucocytes. After the administration of a ten-fold dose of MARVAK vaccine, 80% of the chicks were viraemic and the average titre of viraemia was 8 PFU/10(7) leucocytes. In the MFB vaccinated with the recommended dose of the MARVAK vaccine, the percentage of viraemic chickens was 48.3% and the average titre of viraemia was 6.5 PFU/10(7) leucocytes. In the pullets examined at the age of 20 weeks the number of viraemic birds ranged from 20 to 50% and the average viraemia titres were from 3.8 to 13.1 PFU/10(7) leucocytes. In the flock affected by acute MD, no post-vaccination viraemia was found in the clinically diseases pullets. In the chickens of the HX-SL line vaccinated with the recommended MARVAK vaccine dose, viraemia culminated in the third week after vaccination (31.5 PFU/10(7) leucocytes), and after the use of the dose ten times as high as the recommended one the culmination came a week later (47 PFU/10(7) leucocytes). In the Shaver chicks vaccinated with the recommended dose or with the ten-fold dose of the MARVAK vaccine, the post-vaccination viraemia culminated in the fourth week after vaccination (94.9 and 116.8 PFU/10(7) leucocytes). The post-vaccination precipitation antibodies were first detected in the eighth week after vaccination.  相似文献   

13.
方小友 《蚕学通讯》2001,21(4):43-44
淳安县富文乡重坑村村民方根法 ,全家六口人 ,其中劳力两个 ,现有桑园面积 0 .347公顷 ,其中采叶养蚕面积 0 .2 1 3公顷 ,去冬新种 0 .1 33公顷。去年由于规模生产效益突出 ,曾被评为“淳安县养蚕大户”。今年他更上一层楼 ,全年共饲养蚕种 1 4张 ,产茧 6 0 2公斤 ,产值达 1 .2 4万元 ,平均张产 4 3公斤 ,1 /1 5公顷产茧 1 88公斤 ,1 /1 5公顷产值 3875元 ,蚕茧收入占其家庭总收入的 70 %以上 ,成为远近闻名的养蚕致富带头人 ,现将其栽桑养蚕经验作一总结。1 注重桑园平衡施肥和治虫工作长期的生产实践 ,使他认识到桑园平衡施肥和桑园治虫…  相似文献   

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1. A total of 240 Shaver White and 240 ISA Brown pullets that had been reared in multi-bird cages on a 10-h photoperiod, and maintained at a light intensity of 3 or 25 lux, or changed from 3 to 25 lux or from 25 to 3 lux at 9 or 16 weeks of age, were moved into individual-bird cages at 20 weeks and transferred to 15-h photoperiods at 25 lux. 2. In both breeds, birds transferred from 3 to 25 lux at 16 or 20 weeks laid significantly more eggs than birds maintained on the brighter intensity from one day or increased to it at 9 weeks. 3. Mean egg weight, shell deformation, albumen height, feed intake and body weight gain in lay were not significantly affected by the light intensity treatments during the rearing period. There was, however, a small, but significant, negative correlation of egg numbers with mean egg weight, although this only partially explained the difference in egg numbers. The differences in egg production were unrelated to rate of sexual maturation.  相似文献   

17.
笔者已多年从事蚕桑生产,深入蚕户,积累了许多有用的经验,供广大蚕农借鉴。1“防尘口罩”的制作很多蚕农都知道,杀灭病原,严防蚕病发生,关键是消毒严格、彻底。但在蚕体蚕座使用防僵粉或鲜石灰粉时,灰尘很大,气味刺鼻,所以常常草草了事。要使药物撒周到,很简单,就是把平常用的口罩用水打湿后再用,粉粒就会粘附在口罩上,并且气味也减小了。2经济、实用的熟蚕自动上蔟登蔟剂现有很多蚕农推广熟蚕自动上蔟,这样可以节省劳力和时间。目前农村养蚕用于熟蚕自动上蔟的登蔟剂最常用的有两种,即樟脑丸和鲜腥草(俗名侧耳根),它们都有一种特殊的气味,…  相似文献   

18.
Different infectious bursal disease virus (IBDV) live vaccines (intermediate, intermediate plus) were compared for their immunosuppressive abilities in specific-pathogen-free (SPF) layer-type chickens or commercial broilers. The Newcastle disease virus (NDV) vaccination model was applied to determine not only IBDV-induced immunosuppression but also bilateral effects between IBDV and NDV. None of the IBDV vaccines abrogated NDV vaccine-induced protection. All NDV-vaccinated SPF layers and broilers were protected against NDV challenge independent of circulating NDV antibody levels. Sustained suppression of NDV antibody development was observed in SPF layers, which had received the intermediate plus IBDV vaccine. We observed a temporary suppression of NDV antibody development in broilers vaccinated with one of the intermediate, as well as the intermediate plus, IBDV vaccines. Different genetic backgrounds, ages, and residual maternal antibodies might have influenced the pathogenesis of IBDV in the different types of chickens. Temporary suppression of NDV antibody response in broilers was only seen if the NDV vaccine was administered before and not, as it was speculated previously, at the time the peak of IBDV-induced bursa lesions was detected. For the first time, we have demonstrated that the NDV vaccine had an interfering effect with the pathogenesis of the intermediate as well as the intermediate plus IBDV vaccine. NDV vaccination enhanced the incidence of IBDV bursa lesions and IBDV antibody development. This observation indicates that this bilateral effect of an IBDV and NDV vaccination should be considered in the field and could have consequences for the performance of broiler flocks.  相似文献   

19.
In the specialised rearing house for young cattle of all age groups the occurrence of endoparasites was followed. In the age group of 21 to 90 days, 56% of calves aged about 30 days eliminated oocysts of coccidia. On the whole, 49.3% of calves were infested by coccidia, 3% by enterohelminths. 90.3% of calves aged from three to six months were parasitised by coccidia, 7.4% by enterohelminths. Young cattle, aged from 6 to 12 months, were parasitised in 94.6% by coccidia and in 14.1% by enterohelminths. 86.6% of pregnant heifers at the age of 14 to 19 months had coccidia, 7.7% enterohelminths. The total farm capacity was about 950 animals. Throughout the year the number of examined animals amounted to 1,195, out of this number 958 animals, i. e. 80.2%, were infested by coccidia, 55.6% of animals by the species Eimeria bovis, 47.0% by E. zuernii, 43.3% by E. auburnensis, 39.4% by E. ellipsoidalis, 25.2% by E. cylindrica, 13.6% by E. subspherica, 3.1% by E. bukidnonensis, 1.7% by Isospora spp., 0.4% by E. brasiliensis, 0.08% by E. pellita. Enterohelminths were observed only in 96 animals, i. e. in 8.03%. Trichocephalus was found in 3.9% of animals, Cooperia in 2.4%, Ostertagia in 0.6%, Chabertia in 0.4%, Nematodirus in 0.3%, Capillaria in 0.2%, Oesophagostomum in 0.2%, Bunostomum in 0.1% and Trichostrongylus in 0.1%. The highest elimination of oocysts of coccidia was observed in August, January and February, of eggs of enterohelminths from August to October. In all age groups the most frequent was the occurrence of pathogenic species of coccidia.  相似文献   

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