共查询到20条相似文献，搜索用时 234 毫秒
1.
A serologic survey in unvaccinated broiler parent and broiler progeny flocks demonstrated seroconversion against chicken infecrious anemia virus (CIAV) in all parent flocks before or around point of lay and in 38% of the broiler flocks examined at slaughter age. The presence of CIAV antibodies at slaughter of broilers was positively correlated with slaughterhouse condemnation rates. Results indicate that CIAV infections are highly prevalent in both broiler parent and broiler flocks and that CIAV infections in broilers are associated with increased slaughterhouse condemnation. 相似文献
2.
为了解AA肉种鸡群中免疫抑制性病毒的存在状况及其对NDV疫苗免疫效果和对商品鸡生长的影响,采用多重PCR、RT-PCR和血清学方法对山东某规模化大型AA父母代肉种鸡场的28日龄、180日龄左右种鸡及其所生产的1日龄、30日龄左右商品鸡进行IBDV、MDV、ALV、REV、CIAV及REOV感染状况的调查,并同时对鸡群NDV免疫后抗体水平进行跟踪监测.结果表明种鸡和商品鸡均存在CIAV的感染,并不同程度地存在CIAV与MDV、IBDV等的共感染;发病鸡群NDV抗体水平明显偏低的原因是由于鸡群感染免疫抑制性病毒所致;种鸡群感染CIAV并垂直传播给商品鸡,间接引起商品鸡发生免疫抑制性病毒的共感染,导致商品鸡群30日龄左右生长受阻、免疫能力降低、疾病爆发. 相似文献
3.
4.
《The Journal of Applied Poultry Research》2015,24(1):73-79
A study was conducted in South Georgia to assess the carbon footprint of poultry farms. The study included broiler grow-out farms, pullet farms, and breeder farms from one commercial broiler complex. Data collection included the fuel and electricity bills from each farm, house size and age, flock size and number of flocks per year, and manure management. Emissions were calculated using a greenhouse gas (GHG) calculation tool. The carbon dioxide, nitrous oxide, and methane (CH4) emissions were computed and a carbon footprint determined. Carbon footprint comparisons were made based on house construction and age. Based on these results, an evaluation of the mechanical sources of emissions showed that approximately 96% of the emissions from the broiler and pullet farms were from propane use, while only 3.9% of the total mechanical emissions from breeder farms were from propane use. On breeder farms, 83% of mechanical GHG emissions were the result of electricity use, while the pullet and broiler grow-out farms accounted for 2.9 and 2.7%, respectively, of the total mechanical emissions from electricity use. The data collected from the farms and entered into the GHG calculation tool revealed that breeder houses had higher levels of CH4 emissions from manure management when compared to emissions from broiler and pullet houses. Even though the GHG emissions from poultry production farms were minimal compared to other animal production farms, the different sources of emissions were identified, thereby enabling the farmer to target specific areas for mitigation. 相似文献
5.
Seven chicken infectious anemia virus (CIAV) isolates were obtained from seven broiler flocks with poor performance in two states of Brazil. All isolates induced thymus atrophy, bone-marrow aplasia, and low hematocrit values when inoculated into 1-day-old susceptible chicks. The CIAV isolates were resistant to treatment with chloroform and were able to pass through 50-nm-pore-size filters. CIAV-specific antigens could be demonstrated in tissues of experimentally infected chicks using a monoclonal antibody specific for CIAV. These characteristics of the virus and the virus-induced lesions demonstrate that CIAV is present in Brazil and that the virus is associated with production problems. 相似文献
6.
Eight poultry farms in Nigeria, including chickens from nine breeder, 14 broiler, 28 pullet, 11 layer, and three cockerel flocks, were tested for antibody seroprevalence to the following poultry viruses of potential economic importance: infectious bronchitis virus (IBV), avian reovirus, avian pneumovirus (APV), infectious laryngotracheitis virus (ILTV), avian influenza virus (AIV), and avian leukosis virus (ALV). Serum samples were collected between 1999 and 2004 and were tested for antibodies using commercial enzyme-linked immunosorbent assay (ELISA) kits. Seroprevalence was very high for IBV (84%); intermediate for reovirus (41%), APV (40%), and ILTV (20%); and very low for ALV (<5%) antibodies. By commercial ELISA, the seroprevalence of antibodies against AIV was, in some flocks, up to 63%. However, more specific assays did not confirm AIV antibodies, indicating that all flocks tested were free of avian influenza antibodies. Birds seemed to be first infected by IBV (at about 7 wk of age), then by reovirus at 12 wk, before they became infected by APV (week 25) and ILTV (week 30). This is the first report of serological evidence of the above viruses in West Africa. Further studies are necessary to assess economic losses due to these avian viruses and the costs and benefits of countermeasures. 相似文献
7.
用地高辛标记的核酸(DNA)探针对江都、连云港、苏州、无锡等地3个市县9个养鸡场(户)随机取样,采集106份样品,分别为12日龄～60日龄的肉鸡、蛋鸡的胸腺、法氏囊和脾脏组织,抽提DNA检测CIAV感染情况。鸡传染性贫血病毒阳性鸡只22份,阳性率为20.7%,各鸡场阳性率从5%到50%不等。结果表明,在江苏省的一些地区鸡群中CIAV的感染已非常普遍,有的地区甚至十分严重,控制该病的发生已刻不容缓。 相似文献
8.
Humoral immune responses to chicken infectious anemia virus in three strains of chickens in a closed flock 总被引：1，自引：0，他引：1
This is a comparative study on seroconversion to chicken infectious anemia virus (CIAV) in a closed flock of specific-pathogen-free chickens undergoing a natural outbreak and after vaccination of some of these flocks with a commercial, live vaccine. The N2a strain (B21B21 haplotype) had the highest seroconversion after natural infection (94%) or vaccination (100%), followed by the P2a strain (B19B19) at 75%-82% seroconversion after natural infection and 85% seroconversion after vaccination. The S13 (B13B13) chickens were 26% seropositive after natural infection and 75% seropositive after vaccination. N2a chickens with polymerase chain reaction (PCR)-positive tissues were 97% seropositive compared to 80%-83% PCR-positive and seropositive for the P2a chickens and only 8% seropositive and PCR-positive for the S13 chickens. Seroconversion occurred at or near sexual maturity after natural infection in seven flocks studied. 相似文献
9.
Oluwayelu DO Todd D Ball NW Scott AN Oladele OA Emikpe BO Fagbohun OA Owoade AA Olaleye OD 《Avian diseases》2005,49(3):446-450
Chicken anemia virus (CAV) was isolated for the first time from the Nigerian chicken population. The virus was recovered from necropsied birds from broiler and pullet flocks that suffered disease outbreaks tentatively diagnosed as infectious bursal disease. A sensitive polymerase chain reaction (PCR) assay detected CAV DNA in tissues of necropsied birds. Restriction endonuclease analysis performed with the 733-bp PCR product and the Cfo I enzyme indicated at least two different CAVs were circulating among the Nigerian chicken population. Four isolates were obtained from pooled liver and thymus tissues using the MDCC-MSB1 cell line. These isolates were found to be antigenically closely related to the Cuxhaven-1 (Cux-1) reference strain of CAV when reacted with four monoclonal antibodies prepared against the Cux-1 virus. One of the isolates (isolate A) induced thymus atrophy, bone marrow aplasia, and low hematocrit values when inoculated into 1-day-old specific-pathogen-free chickens. These findings not only demonstrate that CAV is present in Nigeria, but they also likely represent the first cell culture isolation of the virus in Africa. 相似文献
10.
This study was the first to examine the seroprevalence of Ornithobacterium rhinotracheale (ORT) within a commercial egg layer population. Serum samples collected from egg production companies were examined by serum plate agglutination test (SPAT) and outer membrane protein-based enzyme-linked immunosorbent assay (ELISA). Results show that 90% of layer flocks were positive by SPAT and 100% by ELISA. Of the pullet flocks examined, 43% and 52% were positive by SPAT and ELISA, respectively. Our study indicates that the prevalence of ORT antibody is high in the commercial layer population, suggesting that this respiratory pathogen can easily spread through multiple-age layer farms from older flocks to newly housed pullet flocks. 相似文献
11.
12.
13.
Our objectives were to determine Campylobacter prevalence in broiler chicken flocks in Reunion Island and to define specific practices associated with the presence of Campylobacter spp. Infection in Reunionese broiler flocks. Fifty broiler flocks were studied in Reunion Island from May 2007 to February 2009. A questionnaire was submitted to the farmers and samples of fresh droppings were collected to assess the flock's Campylobacter status. Fifty four percent of the flocks were infected by Campylobacter spp.: 30% (95% CI: 28.71-31.29) were infected with Campylobacter coli and 17% (95% CI: 15.95-18.05) with Campylobacter jejuni; only 7% (95% CI: 6.28-7.72) were infected by both species at the same time. Several poultry houses in the farm (OR=11.2; [1.05-92]) and cleaning without any detergent (OR=13.1; [2.1-78.3]) increased the risk of Campylobacter infection. A distance higher than 500 m between broiler farms (OR=0.27; [0.1-0.8]) and use of disinfectant during the rearing period decreased this risk of infection (OR=0.15; [0.1-0.75]). 相似文献
14.
Phylogenetic diversity of parvovirus detected in commercial chicken and turkey flocks is described. Nine chicken and six turkey flocks from Croatian farms were tested for parvovirus presence. Intestinal samples from one turkey and seven chicken flocks were found positive, and were sequenced. Natural parvovirus infection was more frequently detected in chickens than in turkeys examined in this study. Sequence analysis of 400 nucleotide fragments of the nonstructural gene (NS) showed that our sequences had more similarity with chicken parvovirus (ChPV) (92.3%-99.7%) than turkey parvovirus (TuPV) (89.5%-98.9%) strains. Phylogenetic analysis grouped our sequences in two clades. Also, the higher prevalence of ChPV than TuPV in tested flocks was defined. The necropsy findings suggested a malabsorption syndrome followed by a preascitic condition. Further research of parvovirus infection, pathogenesis, and the possibility of its association with poult enteritis and mortality syndrome (PEMS) and runting and stunting syndrome (RSS) is needed to clarify its significance as an agent of enteric disease. 相似文献
15.
Oyebanjo Dayo Oyekole 《Preventive veterinary medicine》1984,3(2):151-158
A deterministic mathematical model is developed for assessing the economic effects of disease outbreaks in broiler chicken flocks. Using the model, this paper estimates the very high cost of disease which occurred on a poultry farm in Ibadan. Nigeria and indicates the wide variety of accurate date required when trying to obtain precise figures for the true financial costs of disease. 相似文献
16.
Arsenault J Letellier A Quessy S Normand V Boulianne M 《Preventive veterinary medicine》2007,81(4):250-264
We conducted an observational study to estimate prevalence and risk factors for Salmonella spp. and Campylobacter spp. caecal colonization in poultry. Eighty-one broiler chicken and 59 turkey flocks selected among flocks slaughtered in the province of Quebec, Canada, were included in the study. Flock status was evaluated by culturing pooled caecal contents from about 30 birds per flock. Exposure to potential risk factors was evaluated with a questionnaire. Odds ratios were computed using multivariable logistic regression.
The prevalence of Salmonella-positive flocks was 50% (95% CI: 37, 64) for chickens and 54% (95% CI: 39, 70) for turkeys, respectively. Odds of Salmonella colonization were 2.6 times greater for chicken flocks which failed to lock the chicken house permanently. In turkeys, odds of Salmonella colonization were 4.8–7.7 times greater for flocks which failed to be raised by ≤2 producers with no other visitors allowed onto the premises, or origin from a hatchery.
The prevalence of Campylobacter-positive flocks was 35% (95% CI: 22, 49) for chickens and 46% (95% CI: 30, 62) for turkeys. Odds of colonization were 4.1 times higher for chicken flocks raised on farms with professional rodent control and 5.2 times higher for flocks with manure heap >200 m from the poultry house, and also increased with the number of birds raised per year on the farm and with the age at slaughter. For turkeys, odds of Campylobacter flock colonization were 3.2 times greater in flocks having a manure heap at ≤200 m from poultry house and 4.2 times greater in flocks drinking unchlorinated water. 相似文献
17.
Manal A. A. Afifi Magdy F. El-Kady Sahar A. Zoelfakar Ahmed Sayed Abddel-Moneim 《Tropical animal health and production》2013,45(2):687-690
Multiple avian influenza viruses’ subtypes are circulating worldwide possessing serious threat to human populations and considered key contributors to the emergence of human influenza pandemics. This study aimed to identify the potential existence of H7 and H9 avian influenza infections circulating among chicken flocks in Egypt. Serum samples were collected from chicken flocks that experienced respiratory distresses and/or variable mortality rates. H7 and H9 virus infections were screened by haemagglutination inhibition assay using chicken erythrocytes. Serum samples were collected from 9 broiler, 12 breeder and 18 layer flocks. Out of 1,225 examined sera, 417 (34 %) from 14 flocks and 605 (49.4 %) from 21 flocks were found positive for H7 and H9, respectively. Prevalence of both H7 and H9 antibodies were higher in layer followed by breeder then broiler flocks. Special consideration should be paid to control influenza viruses in Egypt, as pandemic influenza strains may develop unnoticed given the presence of subclinical infections, and the possibility of re-assortment with the prevailing endemic H5N1 virus strains in Egypt do exist. 相似文献
18.
H Salisch I Erhorn K P Behr O Siegmann 《DTW. Deutsche tier?rztliche Wochenschrift》1989,96(10):493-496
In the period from 1985 to 1987, 24 broiler crops (12 houses; one integration and 3 farms) and 9 pullet flocks (9 houses, 4 farms) were examined for parasites. Intestinal lesion scores and the number of parasites in the intestinal lumen (semiquantitative estimation) were recorded, and the Eimeria species determined when possible (broilers crops: 3rd and 5th week, pullet flocks 4th, 8th, 12th and 18th week). Additionally, the quantity of parasites in litter or faecal samples was examined in regular intervals. Clues for economic damage were only found in broiler crops with increased numbers of coccidial oocysts per gram litter in the 5th week of the fattening period. Eimeria tenella and E. acervulina were the dominating species in broiler chickens and also pullets, E. maxima oocysts however were only casual findings. No ectoparasites, helminths or other protozoa than Eimeria were observed. With regard to the intestinal lesions and the quantities of parasites in the intestine no significant differences were seen when comparing selected broiler chicks and birds taken at random. In pullet flocks the examination of random samples was the superior method, because only freshly dead bodies, collected in insufficient numbers, were suitable for diagnostics. In 3 broiler crops and one flock of replacement pullets kept on a wired floor no Eimeria were diagnosed. 相似文献
19.
Recombinant Protein A, recombinant Protein G, and anti-chicken-IgG anti-bodies raised in rabbits, goats, or horses were found to bind directly to chicken infectious anemia virus (CIAV). MSB-1 cells infected with the Cux-1 strain of chicken anemia agent, but not to uninfected MSB-1 cells were found to react with fluorescein isothiocyanate conjugates. In an enzyme-linked immunosorbent assay, rabbit anti-chicken horseradish peroxidase conjugate bound directly to CIA-1 CIAV-coated plates. In addition, sera from a low percentage of specific-pathogen-free breeder hens reacted in an indirect fluorescent antibody test to detect CIAV antibodies. These reactions generally disappeared within a month. The breeder flocks were demonstrated to be free of CIAV infection by the susceptibility of their progeny. 相似文献
20.
Ornithobacterium rhinotracheale is a gram negative bacterial pathogen causing respiratory tract infections in poultry. Tracheal, lung and serum samples were
obtained from 21 broiler flocks of 8 farms from a slaughterhouse located in south-eastern of Iran. Among 630 tracheal and
lung samples from samples resulting from 315 chickens, 11 (3.5%) ORT isolates were identified using biochemical tests. The
isolates originated from 9 (42.9%) flocks out of 4 farms. All of the isolates were recovered from tracheal swabs and showed
an API 20NE identification biocode 0-2-2-0-0-0-4. Of the 420 serum samples examined by ELISA, 134 (31.9%) sera from 17 (81.0%)
flocks were positive for ORT antibodies. These results indicate that ORT is present in most broiler flocks with respiratory
disorders in southeast Iran. 相似文献