Sick Chickens Research Articles

Avian Flu and the Procurement of Chickens for Culling

Highly pathogenic avian influenza travels from migratory birds via domesticated fowl to humans. A prominent strategy for protecting humans from bird flu is to cull chickens. A hurdle to culling chickens is procuring chickens to be culled. Governments have two extreme options: pay for chickens or seize chickens without compensation. This paper explores the economic and economically-mediated ecological costs of the two different methods of procuring chickens for a cull. Because the question we ask has both economic and ecological components, our approach is to marry an ecological model of flu in chickens with an economic model of markets for chicken meat in developing countries. Because the technology to diagnose flu in chickens is imperfect and not widely available, our analysis assumes that there are false negatives in identification of infected chickens. We draw three primary conclusions. First, purchasing chickens may encourage the production of more chickens, increasing the number of sick chickens, a direct threat to humans. Second, seizing chickens avoids this concern, but may encourage farmers to export chickens to neighboring districts or to delay selling chickens until the culling program is terminated. Therefore and important complement (and cost) seizing chickens is a quarantine to prevent export or an extended culling program to limit storage.

Investigation on Infectious Bursal Disease Outbreak in Debre Zeit, Ethiopia

2 Abstract: An outbreak of infectious bursal disease affecting 20-45 days old broiler and layer chickens was investigated for the first time in Ethiopia in the months of March and April 2002. Death of chickens started at the 30 day of age and continues to the 55 day. The mortality rate of the disease in different poultry houses th th ranges from 45-50 %. The over all mortality rate was 49.89%. Broiler mortality was 56.09% while 25.08% for layer chickens. The major clinical symptoms were sudden drop in feed and water consumption, sever depression, white watery droppings and mass death. Grossly, hemorrhages in leg muscles, degeneration of the pectoral muscle, white mass (Urate deposit) in kidneys and in Cloaca were frequently observed during post mortem examination. In addition, haemorrhagic & swollen bursas filled with straw colored fluid were identified in few cases. Histopathology revealed hyperplasia of the reticulo-endothelia cells and interfollicular tissue of affected bursa of fabricius. The Agar Gel Immuno Diffusion (AGID) Test detected precipitating antibodies against Infectious Bursal disease virus in sera collected from convalescent chicken. Virus cytopathic effect was observed in chicken fibroblast cells (CFC) inoculated with bursa and spleen tissue suspension of sick chicken. Vaccination failures were encountered to Newcastle disease vaccine (Clone 30). This paper probably is the first to report the occurrence of infectious bursal disease in Ethiopia as the country has been known to be free from Infectious Bursal Disease(IBD).

Village Chicken Flock Dynamics and the Contribution of Chickens to Household Livelihoods in a Smallholder Farming Area in Zimbabwe

The development of successful production strategies for poultry rearing depends on an accurate description of village chicken production systems. In Rushinga District of Zimbabwe, participatory rural appraisals (PRAs) followed by checklists and intensive case studies were carried out in three villages. The role of chickens in the livelihoods of households was evaluated. Flock dynamics were monitored monthly for 24 months. Women who were resident on the farm headed 19% of the households. A household comprised 4.8 +/- 2.5 members with arable land of approximately 2.6 ha. In addition to chickens, households grew maize, cotton and sunflower and kept large animals. Flocks ranging from 1 to 50 village chickens per household were reared under a scavenging system of management with suboptimal housing, inadequate feeding and poor health care. The use of ethno-veterinary medicine was common in treating sick chickens. The largest flock sizes were observed in the hot-wet season. Over 90% of an average of 5.4 entries/household per month were from hatched chicks. Mortality claimed an average of 80% of the total exits. Chicken production potential (CPP), which defined the proportion of chickens that could be utilized by a household, averaged 50%. Chicken production efficiency (CPE) was approximately 15% of the CPP. Egg consumption patterns were low and similar across seasons.

Systemic and mucosal antibody responses to selected cell surface antigens of avian pathogenic Escherichia coli in experimentally infected chickens.

The immune response to four cell surface antigens of avian pathogenic Escherichia coli (APEC) was investigated as the first step in identifying vaccine candidates. F1 pilus adhesin, P pilus adhesin, aerobactin receptor protein, and lipopolysaccharide (LPS) from an O78 E. coli (strain EC99) were used as antigens. The proteins were purified as 6xhistidine-tagged recombinant proteins and LPS was purified from a phenol/water extract. Groups of 12 broiler chickens were vaccinated intranasally with the EC99 strain and challenged with the same strain 10 days later via the intra-air sac route. The chickens that survived were euthanatized 10 days postchallenge. Scores were assigned to infected chickens on the basis of lesions and recovery of the challenge E. coli. The immunoglobulin (Ig) IgG, IgA, and IgM antibodies to the four antigens were measured in serum and air sac washings in an enzyme-linked immunosorbent assay. Among the chickens that were not vaccinated prior to challenge, two died and three of the survivors were ill, whereas, of the chickens that were vaccinated prior to challenge, one died and one of the survivors became ill. After the intranasal vaccination, high antibody activity against all four antigens was associated with each Ig isotype in serum and air sac washings. IgG was the predominant isotype of Ig in air sac washings as detected by radial immunodiffusion. Chickens that were not ill after challenge had greater IgG, IgA, and IgM antibody activity against all four antigens in serum and air sac washings than did sick chickens. Thus, all of the antigens tested appear to be suitable candidates for a vaccine to protect chickens from respiratory tract infections caused by APEC.

Chicken Infectious Anemia in Mexico: Virus Identification and Serology Survey

Three chicken infectious anemia (CIA) virus strains were isolated from 10 different sick broiler and replacement chicken flocks with the MDCC-MSB1 cell line. One-day-old specific-pathogen-free chicks were inoculated later, with the three original samples being positive in tissue culture; one induced signs and lesions, another only lesions typical for CIA. One isolate was selected for further trials and showed resistance to chloroform and heat (75 C for 5 min) and passed through a 45-nm filter membrane but did not pass through the 22-nm filter. These characteristics were similar to the Del Rose reference strain of chicken anemia virus. By electron microscopy, the diameter of particles obtained from the pellet of infected cell cultures was between 22 and 27 nm. Serology survey carried out with 580 serum samples from different poultry farms all over the country with a commercial enzyme-linked immunosorbent assay kit gave proof of widespread seroconversion, indicating that CIA should be considered endemic to Mexico.

Diseases and management of indigenous chickens in Oodi, Kgatleng, Botswana

A total of 215 indigenous chickens were found in 10 homesteads visited in Oodi, Kgatleng, Botswana from June to July 1999. The mean (SD) flock size was 21.5 (11.6) with a range of 7–47. The chickens were not housed but instead spent the night on top of trees to escape predation. Vaccinations against poultry diseases such as Newcastle disease were not carried out. Instead, traditional herbal remedies were used to treat sick chickens. Only a few adult birds were infested with scaly leg mites and fleas. Worm eggs were not detected in faecal samples examined but some coccidial oocysts were seen. Antibodies to avian infectious bronchitis, infectious bursal disease, Mycoplasma gallisepticum and egg drop syndrome were demonstrated in some of these chickens, suggesting previous infections or exposure.

Indigestion of Identities

Indigestion of Identities

Experimental assessment of the pathogenicity of the Newcastle disease viruses from outbreaks in Great Britain in 1997 for chickens and turkeys, and the protection afforded by vaccination

The Newcastle disease virus isolated from healthy turkeys in outbreak GB 97/6 was used to challenge 4-week-old turkeys and chickens, which were either not vaccinated or had received a single dose of Hitchner B1 live vaccine 14 days earlier, by one of the intramuscular, intranasal or contact routes. Similar experiments were done in 38-day-old turkeys and chickens using virus isolated from severely sick chickens in outbreak GB 97/1. All vaccinated chickens showed low but measurable immune responses 14 days after vaccination, but only three of the turkeys had detectable antibodies. No vaccinated turkey or chicken showed any clinical sign after challenge with either virus. The virus from healthy turkeys in outbreak GB 97/6 induced clinical signs in 12/30 unvaccinated turkeys after challenge and 7/30 died. In unvaccinated chickens, challenge with this virus produced clinical signs in 25/30 birds and 21/30 died. In challenge experiments with the virus from outbreak GB 97/1 in chickens, 3/30 unvaccinated turkeys showed clinical signs and all three subsequently died. In contrast, 30/30 unvaccinated chickens challenged with this virus showed clinical signs and died. Vaccination did not prevent infection and excretion of either challenge virus. However, when compared with unvaccinated birds, vaccination reduced significantly the length of time virus was excreted and the overall proportion of swabs that were positive.

The ratio of the water and food consumption of chickens and its significance in the chemotherapy of coccidiosis.

An investigation was made of the relationship between the water and food consumption of healthy and sick chickens Using coccidiosis as a disease model, and uninfected chickens as healthy controls, male birds of an egg-production breed and males and females of a meat-production breed were found to have simultaneously reduced water and food intakes 4 days after infection with Eimeria acervulina or E. maxima, and from 4 to 6 days after infection with E. tenella. This phenomenon was associated with reduction of weight gains and poor food conversion ratios. Whether birds were healthy or sick, and regardless of the degree reduction of dietary intake, there was a more or less constant relationship between their food and water consumption. The ratio of the weights of water and food consumed had a value of about 1.9, with a range of 1.1-2.4. It is concluded that neither water nor food has an advantage over the other as a vehicle for chemotherapy. However, other factors, such as case and speed of administration, and avoidance of adsorption onto food particles, favour the drinking-water route.

Invasion of Caco-2 Cells by Salmonella typhimurium (Copenhagen) Isolates from Healthy and Sick Chickens

In a previous study, Salmonella isolates of sick birds were distinguished from those of apparently healthy birds by their high degree of invasion of tissue culture cells. In this study, a single pair of Salmonella isolates was examined to determine the source of this observed difference in invasion. When isolates were allowed to invade Caco-2 cells for 8 hours, the isolate from the sick bird (S) appeared to invade in greater numbers than did the isolate from the healthy bird (H). However, when invasion was distinguished from intracellular growth/survival, it was found that H invaded in greater numbers than S, but once inside the cell, H declined in number, and S increased. Inhibition of RNA, protein, and DNA syntheses lessened the degree to which both invaded. The presence of mannose inhibited invasion by S but did not appear to inhibit invasion by H. Trypsin treatment of monolayers affected invasion of S and H, whereas neuraminidase treatment did not. There was no significant difference noted between S and H in ability to adhere to fixed monolayers. Therefore, the two isolates tested differ in their mechanisms of entry into Caco-2 cells, the efficiency with which they invade, and their ability to survive within Caco-2 cells.

B Haplotype Influence on the Relative Efficacy of Marek’s Disease Vaccines in Commercial Chickens

The objectives were to investigate whether or not B haplotypes influence vaccinal immunity against Marek’s disease (MD) in commercial chickens and to evaluate whether retrospective analysis would detect the influence. This method involved evaluating the B haplotypes of turkey herpesvirus (HVT)-vaccinated sick vs normal chickens from a flock afflicted with MD symptoms. An analysis of the retrospective data disclosed that MD symptoms were present in a higher proportion of B2B19 than B2B21 chickens. A prospective study was then conducted with blood-typed chickens of the strain vaccinated with HVT or HVT+301B bivalent MD vaccines prior to inoculation of the very virulent Md5 virus. The bivalent vaccine provided better protection than HVT alone, but with either vaccine fewer B2B21 chickens developed MD lesions. We conclude that the B haplotype influence on vaccinal immunity against MD previously demonstrated in B-congenic strains of chickens is also significant in commercial chickens and that the influence can be detected through analysis of B haplotypes in sick vs normal chickens of an affected flock.

Classification, Pathogenicity, and Drug Susceptibility of Hemolytic Gram-Negative Bacteria Isolated from Sick or Dead Chickens

Fifteen hemolytic gram-negative bacteria were isolated from the respiratory tracts of sick birds suffering from a long-lasting respiratory syndrome or from the bone marrow of dead birds distributed in the southern part of Taiwan. These were classified as Pseudomonas aeruginosa (10 isolates), Pseudomonas fluorescens (2 isolates), Pseudomonas stutzeri (1 isolate), Pasteurella haemolytica (1 isolate), and Proteus morganii (1 isolate). Each isolate was inoculated intraperitoneally into one group of ten 4-week-old male white leghorn chickens. Mortality and lesions were scored daily for 1 week. Three of the 10 isolates of Pseudomonas aeruginosa caused 100% mortality. Six other isolates of Pseudomonas aeruginosa and the one isolate of Proteus morganii caused 50% mortality. The remaining isolates induced less than 30% mortality. The sole nonpathogenic sample was one isolate of Pseudomonas fluorescens. When therapeutic levels of 22 antibiotics or sulfa drugs were evaluated for their inhibitory activity against the 15 isolates, the most effective were apramycin (15/15), gentamicin (15/15), spectinomycin (13/15), oxytetracycline (8/15), and sulfachloropyrazine (7/15). The least effective were ampicillin, cloxacillin, and tiamulin, which were not effective against any of the isolates. The 14 other drugs were of very low (> 4/15) effectiveness. Most of the isolates studied were virulent for chickens and very resistant to currently used drugs.

Antimicrobial resistance of Escherichia coli isolated from chickens

Faecal Escherichia coli isolated from healthy farm chickens, from farm chickens with avian influenza, and from chickens with diarrhoea were more resistant to antimicrobial agents (94–100%) than those isolated from healthy domestic chickens (20%). Transfer of drug resistance was readily achieved from strains isolated from both healthy and sick farm chickens, and from diarrhoeic chickens; it was more difficult to demonstrate in strains from domestic chickens. Resistant E. coli showing serotypes suspected to be enteropathogenic for man, i.e. 0126: K71 (B16), 044: K74 (L) and 0119: K69 (B14), were isolated from faecal samples of healthy and sick farm chickens, but not from healthy domestic birds.

Beitrag zur differenzierung von haemophilus‐stämmen aus hühnern*

Thirty-one isolates of Haemophilus organismus, most of them isolated from respiratory organs of sick chickens, and 3 Haemophilus gallinarum strains from California (USA) were culturally and biochemically investigated. Two groups of Haemophilus strains were differentiated. Of the 23 isolates belonging to group I, 22 were obtained from chickens with Coryza contagiosa gallinarum. One strain was isolated from the eye of a sick chicken. These microaerophilic strains required the V factor only and failed to grow aerobically in serial passage on tryptose agar. Six isolates required chicken serum (not X factor) besides V factor for growth on tryptose agar and they fermented solely xylose. All strains were primarily capsulated and showed iridescent colonies on tryptose agar. They were catalose- and indole negative, produced nitratase; fermented glucose, fructose, mannose, but not trehalose, inulin, salicin, dulcitol, galactose and lactose. Not all of them were capable of fermenting saccharose, maltose, dextrin, sorbitol, xylose and mannitol. The strains 0083 and 0222 from USA were similar to isolates of group I, however they showed a partially different fermentation pattern from that described by Page (1962). After the proposal of Biberstein and White (1969) the Haemophilus strains of group I should be named Haemophilus paragallinarum by reason of their X factor independence and the rules of nomenclature. The 8 isolates of group II grew well aerobically, showed iridescence, were primarily capsulated and required the V factor. These strains were catalase positive, indole negative and produced nitratase; fermented glucose, fructose, mannose, galactose, saccharose and trehalose; but not lactose, inulin, salicin and dulcitol. Some isolates fermented also xylose, maltose, dextrin, sorbitol and mannitol. On the basis of the results of cultural and biochemical investigations these strains were assigned to the group of apathogenic Haemophilus strains described by Page (1962) and Robert et al. (1964).

Diseases

New opinions regarding Paullorum Disease. Nouveaux points de vue sur la pathogenie, le traitement et La prophylaxie de la septicémie des volailes dae à la Salmonella pullorum. Dr. J. Ch. Sparaparri. La Revue Avicole, 1937, p.453.The pullorum bacil in itself does not cause the disease. It is only when the chickens are in a weakened state that the disease appears and then the bacilli are able to increase considerably. The writer considers lack of certain vitamins (A., B, C) to be the cause of weakness. This lack of. vitamins need not be present to such an extent as to cause avitaminosis, but only to such a degree as will cause a decrease of the powers of resistance in the body to the increase of the pullorum bacilli. The writer cured several chickens suffering from pullorum by a method of his own. In experiments carried out according to Harde's method a smaller quantity of vitamin C was found in the livers of sick chickens than in those of healthy ones. The quantity of vitamin A. was also smaller. Cure was affected by subcutaneous injections of Vit. A, B, and C.

A Federal Administrative Court

During the past year the decisions of the United States Supreme Court in the hot oil 1 and the sick chicken 2 cases have been cited so frequently and for so many different propositions, that both the possibilities of the cases and the patience of the listening public might justly be regarded as exhausted. The proposal of the Special Committee on Administrative Law of the American Bar Association for the establishment of a federal administrative court affords, however, an opportunity for reference to them from a point of view which has received very little attention. The cases are important to the proposal, not in furnishing any direct authority one way or the other, but in suggesting an interesting contrast. In one field of administrative law, having to do with delegations of legislative power to executive or administrative agencies, the Supreme Court has, with these decisions, at last made progress toward some sort of a boundary line between two of the three great departments of government under our Constitution. At least, the Court has recognized that there is a boundary line. In the equally important sister field, having to do with reposing judicial power in such agencies, we are still not only without any semblance of a boundary line but are actually faced with a disheartening maze of conflicting notions as to where that line should be drawn and at times even with doubts as to whether any line exists. In its opinions in these two cases last year, the Supreme Court of the United States declared for the first time in positive terms that there are bounds which Congress may not transgress in delegating legislative power to the Executive. Superficially, it seems strange that we have waited so long for judicial repair of this essential but somewhat damaged pillar in our national structure. The doctrine of separation of governmental powers into legislative, executive and judicial is one feature of our Constitution that cannot rightly be blamed on the laissez-faire philosophy of poor old Adam Smith. The doctrine was written into our fundamental law plainly enough,