养鸡场鸡肾型传染性支气管炎的科学防控

鸡肾型传染性支气管炎是鸡传染性支气管炎的一种病理性表现形式。自上世纪90年代以来,鸡肾型传染性支气管炎在我国的一些养鸡场中相继暴发,且流行较广泛,尤其是近年来,鸡肾型传染性支气管炎在我国的养鸡场(尤其是肉鸡养殖场)中呈现大面积流行,给养鸡生产带来了严重的损失,因此,养鸡场科学地防控鸡肾型传染性支气管炎已经成为了目前防控鸡病的重点工作之一。     

鸡肾型传染性支气管炎的诊治

鸡肾型传染性支气管炎是由冠状病毒科的传染性支气管炎病毒引起的鸡的一种急性接触性传染病,主要引起鸡水样腹泻和间质性肾炎,造成肾脏损伤,死亡率高,也能造成呼吸道感染,是影响养鸡业的重要传染病之一。2009年6月21日,烟台市福山区某养殖场发生鸡肾型传染性支气管炎。根据疾病流行特点、临床症状、剖检变化及实验室检查,诊断为鸡肾型传染性支气管炎。     

补充电解质对鸡肾型传染性支气管炎死亡率的影响

鸡肾型传染性支气管炎是由鸡肾型传染性支气管炎病毒引起的以呼吸困难、肠炎和肾炎为特征的传染病,在自然条件下仅感染鸡并引起发病。该病于2000年前后     

鸡肾型传染性支气管炎的诊断及治疗

为了促进养殖业的快速发展,养殖户对于家鸡各种疾病的预防和治疗显得尤为重要。尤其是传染性疾病,一旦大面积爆发,对于养殖户的损失将是无法预计且不可估量的。在众多的疾病中,鸡肾型传染性支气管炎是一种高度接触性的疾病,对于家鸡的危害尤为严重。鸡肾型传染性支气管炎,是一种由传染性支气管炎病毒引发的急性、高度接触性传染病。主要的发病群体为家鸡,偶见于鹌鹑等飞禽。鸡肾型传染     

不同中药方剂对鸡肾型传染性支气管炎的疗效观察

鸡肾型传染性支气管炎(IB)是由肾型鸡传染性支气管炎病毒(IBV)所引起的一种以肾脏病变为主的高度接触性病毒性传染病, 该病毒可引起雏鸡死亡,产蛋鸡的产蛋量和蛋的质量均下降,是目前发生较多、流行范围广、雏鸡死亡率高的一种严重传染病之一.试验根据鸡肾型传染性支气管炎的发病特点和发病机理,并按照中兽医"扶正固本、清热解毒"的原则拟定了Ⅰ号、Ⅱ号、Ⅲ号中药配方,以观察各配方对鸡肾型传染性支气管炎的治疗效果.     

中药治疗鸡肾型传染性支气管炎

中药治疗鸡肾型传染性支气管炎汪德刚，刘兴友（郑州牧专４５０００３）鸡肾型传染性支气管炎是由冠状病毒属传染性支气管炎病毒（ＩＢＶ）引起的一种以侵害鸡肾脏为主的急性高度接触性传染，且对生产危害很大的呼吸道和泌尿生殖道疾病。国内１９８２年在广东首次发现，１...     

中西医结合治疗鸡的肾型传染性支气管炎

鸡肾型传染性支气管炎是由传染性支气管炎病毒引起的一种急性、高度接触性呼吸道传染病——传染性支气管炎中的一个症型（另有呼吸性和生殖异常型等症型）,多发于20～60日龄的雏鸡。     

鸡肾型传支病毒RZ株的分离及鉴定

从某一疑似鸡肾型传染性支气管炎发病鸡场的病死鸡的肾、肝组织中分离到一株病毒，经鸡胚连续传代和动物回归实验，初步确定该病毒为鸡肾型传染性支气管炎病毒，命名为IBV-RZ株。     

黑龙江省鸡肾型传染性支气管炎病毒的分离和鉴定

黑龙江省鸡肾型传染性支气管炎病毒的分离和鉴定＠李海滨＠高力＠李一经￥东北农业大学动物医学系＠李学珍￥黑龙江省青年农场黑龙江省鸡肾型传染性支气管炎病毒的分离和鉴定李海滨高力李一经（东北农业大学动物医学系,黑龙江哈尔滨１５００３０）李学珍（黑龙江省青年农场）鸡...     

乌骨鸡发生肾型传染性支气管炎的诊治

乌骨鸡发生肾型传染性支气管炎的诊治袁录（河南省南阳农业学校４７３０５５）鸡肾型传染性支气管炎（以下简称肾传支）是由传染性支气管炎病毒肾病变异毒株引起的一种急性、高度接触性传染病。近年来，见到不少有关鸡肾传支的报道，但有关乌骨鸡肾传支的报道比较少见。自...     

鸡肾型IBV的分离及其N基因的克隆与测序

通过病毒形态学观察、血凝试验、病毒干扰实验、动物回归实验等分离鉴定了1株鸡肾型传染性支气管炎病毒.利用RT-PCR技术对分离毒株的N基因进行了扩增,经克隆、序列测定和分析,证实分离株为肾型IBV.     

SOME IMMUNOLOGICAL ASPECTS OF A RECENT AUSTRALIAN ISOLATE OF INFECTIOUS BRONCHITIS VIRUS

An infectious bronchitis virus, designated G48, isolated from birds during an outbreak of nephritis in a previously vaccinated broiler flock, overcame the resistance induced in birds vaccinated with 2 commercially available vaccines. Birds vaccinated with the A isolate of infectious bronchitis resisted challenge with this new virus. Cross neutralisation studies revealed that the new virus was serologically distinct from the 4 viruses tested. Homologous antiserum to G48 did not neutralise the other viruses and only antiserum to the A virus completely neutralised the new virus.     

Renal pathology in specific-pathogen-free chickens inoculated with a waterfowl-origin type A influenza virus

Five-week-old specific-pathogen-free chickens inoculated intravenously with a waterfowl-origin type A influenza virus (A/mallard/Ohio/184/86) had swollen and mottled kidneys on days 3, 5, and 7 postinoculation (PI) and multiple raised nodules on days 5, 10, and 20 PI. Histologically, the kidneys had multifocal heterophilic tubulointerstitial nephritis with epithelial necrosis on day 3 PI, lymphoplasmacytic tubulointerstitial nephritis on day 5 PI, and fibrosing interstitial nephritis with cortical lobular collapse, atrophic tubules, glomerular aggregates, and interstitial lymphoid follicles and aggregates on days 7, 10, and 20 PI. Heterophilic intratubular medullary-cone nephritis was present in dead or moribund chickens on days 3 and 5 PI. Furthermore, the presence of mild multifocal heterophilic tubulointerstitial nephritis on day 20 PI suggests that a waterfowl-origin strain of type A influenza virus of low pathogenicity has the potential to produce acute and chronic active nephritis in the chicken and that the kidney is a potential site for influenza viral persistence. The acute, subacute, and chronic histopathologic renal lesions of this influenza virus in chickens are similar to lesions reported for some nephropathogenic infectious bronchitis viruses and avian nephritis picornavirus.     

Detection of avian nephritis virus in Australian chicken flocks

Avian nephritis virus (ANV) is thought to infect poultry flocks worldwide, but no confirmed case has been reported in Australia. The first such case is described in this study. Cases of young chickens with clinical signs of dehydration and diarrhea were submitted to our laboratory and histopathology detected interstitial nephritis. Vaccine strains of infectious bronchitis virus were detected in some of these cases but were not considered to be the causative agent. A total of seven fresh submissions from broiler chicken flocks were collected at 8-11 days of age. Degenerate PCR primers were designed based on published ANV polymerase gene sequences and used to analyze historic cases as well as the fresh submissions. Six of the seven fresh submissions, and one historic case, were positive for ANV with nucleotide sequencing confirming these results. These results establish ANV as an infectious pathogen circulating in Australian poultry.     

Serological monitoring on layer farms with specific pathogen-free chickens

To monitor the existence of avian pathogens in laying chicken flocks, specific pathogen-free (SPF) chickens were introduced into two layer farms and reared with laying hens for 12 months. SPF chickens were bled several times after their introduction and examined for their sero-conversion to avian pathogens. As a result, antibodies to eight or ten kinds of pathogens were detected in SPF chickens on each farm. Antibodies to infectious bronchitis virus (IBV), avian nephritis virus, Mycoplasma gallisepticum and M. synoviae were detected early within the first month. Antibody titer to IBV suggested that the laying chickens were infected with IBV repeatedly during the experiment on both farms. However, antibodies to infectious bursal disease virus and 6 pathogens were not detected.     

Pathological and aetiological studies of multifocal interstitial nephritis in wasted pigs at slaughter

Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out.     

Comparison of the nephropathogenicity of four strains of infectious bronchitis virus

Experiments were conducted to characterize renal lesions in chickens induced by four strains of infectious bronchitis virus (IBV); each has been described as nephropathogenic. Those strains were also compared in vaccinated and unvaccinated older chickens for nephropathogenicity. The younger birds were much more susceptible to the nephritogenic effects of the strains. All four strains produced acute renal changes consisting of tubular damage and interstitial inflammatory cell infiltration and edema. Although both cortex and medulla were involved, the latter was generally affected more severely. The Holte strain proved to be the least pathogenic, followed by the more pathogenic Gray and Italian strains and finally by the Australian strain. All four strains produced similar chronic renal changes in unvaccinated birds, with no correlation to the severity of lesions seen at the acute phase. Chronic active and inactive types of interstitial nephritis were seen at the chronic phase. Vaccinated birds challenged with the Australian strain had the highest prevalence of the chronic active type of interstitial nephritis. The implication of renal viral persistence in the development of chronic active interstitial nephritis is discussed.     

The effect of route of infection and strain of virus on the pathology of Australian infectious bronchitis

The pathogenesis of infectious bronchitis in 4-week-old chickens was studied following administration of Australian T strain of IBV by the aerosol, conjunctival, intranasal, in-contact and drinking water routes.
Infected birds showed similar patterns of clinical signs, gross and histopathological lesions. While the birds infected by the aerosol route had earlier and slightly more severe respiratory tract disease it was concluded that the pathogenesis of infectious bronchitis virus nephritis was not significantly influenced by the route used to infect the birds.
In a second experiment, pathological changes produced in chickens infected with Australian S, A, A³ and T strains of IBV were compared in 18-day-old chickens infected by the aerosol route and housed in cold and warm environments. All 4 strains produced respiratory reactions and kidney lesions, and these changes were more severe and of longer duration in both respiratory tract and kidneys in the birds housed in a cold environment than those receiving supplementary heat.
The viruses differed in their virulence for the trachea and kidney and the effect of a virus on the respiratory trace was independent of the effect of that virus on the kidney.