Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “POULTRY DISEASES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed1975

Factors affecting liver fat accumulation and liver hemorrhages associated with fatty liver-hemorrhagic syndrome in laying chickens.

A series of four experiments was conducted with a commercial strain of laying chickens in an attempt to experimentally produce Fatty Liver-Hemorrhagic syndrome (FLHS). Different dietary energy sources, environmental temperatures and feeding schedules were the experimental variables. Increasing the environmental temperature from 12.2 degrees C. (experiment 1) to 27.8 degrees C. (experiment 2) did not drastically alter total liver fat, 2.7 g. (experiment 1) vs. 2.9 g. (experiment 2) or the incidence of FLHS, 0.0% (experiment 1) vs. 1.0% (experiment 2). Likewise, in experiment 4, changing the environmental temperature from 22.2 degrees C. to 30.6 degrees C. or from 30.6 degrees C. to 22.2 degrees C. did not significantly (P greater than .05) alter total liver fat or liver wet weight. The greatest incidence (50%) of FLHS occurred in birds which were restricted in feed intake and exposed to an environmental temperature of 30.6 degrees C. from 32-36 weeks of age followed by ad libitum feeding at a temperature of 22.2 degrees C. from 36-40 weeks of age. These birds ate 26.8% more feed than the control birds during the ad libitum feeding period. Restricted feed schedules (experiment 3) resulted in significantly (P less than .05) lower 40 week liver wet weights and total fat when applied during the growing (14-20 weeks of age) and early lay (20-28 weeks of age) periods.

Age Factors↗
PubMed1977

Effects of T-2 toxin on reproductive performance and health of laying hens.

Purified T-2 toxin was fed to S.C.W.L. hens at levels of 0 (control), 0.5, 1.0, 2.0, 4.0 and 8.0 p.p.m. of an otherwise balanced diet. Feed consumption, egg production and shell thickness were significantly (P less than 0.05) decreased in hens fed 8 p.p.m. as compared with control hens. The fertility and progeny performance were not depressed by feeding T-2 toxin, but the hatchability of fertile eggs of hens fed 2 and 8 p.p.m. was significantly (P less than 0.05) lower than that of hens fed the control diet. The weights of liver, heart, gizzard and spleen were not influenced by T-2 toxin. Serum levels of alkaline phosphatase, LDH and uric acid of hens fed high concentrations of T-2 toxin were greater than those of control hens. SGPT in hens fed 8.0 p.p.m. was lower when compared with control hens. No outward changes in hematocrit, hemoglobin, erythrocyte, leukocyte and differential leukocyte counts were noted with feeding T-2 toxin. Most hens fed T-2 toxin developed oral lesions: circumscribed proliferative yellow caseous plaques at the margin of the beak, mucosa of the hard palate and angle of the mouth, and tongue. The incidence and severity of lesions were proportional to the dietary level of T-2 toxin. The only other lesion observed in necropsy examination at the end of the experiment was the small mucosal ulcer in the anterior portion of the gizzard in hens fed high levels of T-2 toxin. Microscostrointestinal tract, etc.) revealed no significant pathological change except the necrotic lesions in the gizzard and crop.

Alanine Transaminase↗
PubMed1978

Influence of diet composition on hepatic lipid accumulation and hemorrhages in caged layers.

Four experiments were conducted with commercial strains of White Leghorns. Experimental corn-soy diets with (CSW) and without (CS) minor feed ingredients significantly elevated liver and plasma lipids when compared to a standard layer diet (UGA) used at the University of Georgia. The response was not due to difference in vitamin and mineral premix or level of energy and protein in the diets. Inclusion of 5% alfalfa in a low protein (13.5%) diet with energy and amino acid profile similar to diet CS significantly reduced liver lipid. Comparison of diet CS to isocaloric and isonitrogenous diets with 20% brewers dried grains, soybean mill feed, or wheat bran showed that layers fed diets with these supplements had significantly lower liver and plasma lipids. In all experiments a higher incidence of liver hemorrhage was associated with feeding the experimental diets CS and CSW. There were no significant differences in egg production, egg weight, or body weight change due to dietary treatment in the experiments. Results of the experiments show that hens with equivalent ME intake and egg output exhibit differences in liver and plasma lipids due to diet composition. The data suggest that mill feeds and fermentation by-products contain an essential factor for control of lipid metabolism in caged layers.

Animal Feed↗
PubMed1979

In vitro studies on the role of the macrophages of resistant and susceptible chickens with Marek's disease.

Macrophages, from susceptible S- and resistant K-strain White Leghorn chickens, were studied in vitro to determine their contribution to the dynamics of Marek's disease (MD) and possible role in genetic resistance to this disease. In relation to basic macrophage properties (morphology, cell spreading, enzyme levels, pinocytosis, and phagocytosis) there were no significant differences between S- and K-strain macrophages. Both macrophage strains were observed to respond to JM virus by phagocytic responses, but no viral replication or transference of infectivity was observed within inoculated macrophage cultures. In general, there were no differences between S- and K-strain macrophages in vitro that may account for the genetic resistance or susceptibility to MD.

Animals↗
PubMed1979

Incidence of degenerative myopathy among turkeys fed corn or wheat based rations.

Turkeys were fed either corn based or wheat based rations and necropsied between 28 and 118 weeks of age. Practically all birds affected with degenerative myopathy were detected among those killed between 77 and 85 weeks of age. The incidence of the disease was 0% among 125 males and 7.9% among 139 females. No significant difference in incidence was observed between birds fed corn based and birds fed wheat based rations.

Animal Feed↗
PubMed1980

Long term effects of Marek's disease vaccination with cell-free herpesvirus of turkey and age at debeaking on performance and mortality of white leghorns.

Three-hundred-sixty, day-old Single Comb White Leghorn chicks were randomly placed in 8 treatment combinations. The combinations consisted of vaccinated or nonvaccinated chicks that were either not debeaked, or debeaked at day-old, 4 weeks old, or 8 weeks old. Vaccinated birds received 6,000 plaque forming units of cell-free herpesvirus of turkey vaccine per chick at day-old. Debeaking was performed by removing approximately two-thirds of the upper beak. Data were analyzed at the 5% level of probability. During the growing period (8 to 20 weeks of age), averag daily feed consumption per bird and feed efficiency for the vaccinated birds were not significantly different from those for the nonvaccinated. Regardless of the age at which debeaking was performed, the debeaked birds consumed significantly less feed and had superior feed efficiency than the nondebeaked birds. These traits were not significantly different among the various debeaked groups. Vaccination, or debeaking, or age at debeaking did not significantly influence mortality during the growing period. During the laying period (20 to 84 weeks), a significantly higher percentage of extra large eggs and a significantly lower percentage of medium eggs were collected from the vaccinated birds in comparison to those collected from the nonvaccinated. Also, average egg weight for the vaccinated birds was significantly heavier than that for the nonvaccinated. Debeaking at either 4 weeks or at 9 weeks of age caused a significant reduction in egg weight. Vaccination, or debeaking, or age at debeaking did not significantly influence hen-day egg production. Feed efficiency between the vaccinated and the nonvaccinated birds was not significantly different. Debeaking tended to improve feed efficiency. Vaccination as well as day-old debeaking significantly reduced laying house mortality. Debeaking the birds either at 4 weeks or at 8 weeks of age reduced laying house mortality numerically.

Animals↗
PubMed1980

Magnesium toxicity: bone lesions.

Broiler chicks fed corn-soy rations supplemented with toxic levels of magnesium from one day of age grew poorly, developed diarrhea, and exhibited characteristic skeletal abnormalities. Tibiae from magnesium intoxicated chicks were shortened, thickened, and bowed. Percent tibial ash was greatly reduced. Upon microscopic examination, the bone lesion appeared rachitic as evidenced by widened and lengthened growth plates, excessive osteoid seams on endochandral bone, and osteoid or bone capped metaphyseal blood vessels with very few associated osteoblasts. Tibial calcium to phosphorus mass ratios decreased while tibial magnesium to phosphorus mass ratios increased concomitantly with increased dietary magnesium. Calcium and phosphorus homeostasis was possibly affected as evidenced by a general decrease in size and cellularity of parathyroid glands and a general increase in size and cellularity of ultimobranchial glands.

Animals↗
PubMed1981

Reduced vaccinal protection of turkey herpesvirus against field strains of Marek's disease herpesvirus.

Four isolates of Marek's disease herpesvirus (MDV) were obtained from 21-week-old broiler breeders with lesions and mortality from Marek's disease (MD). They had been properly vaccinated with turkey herpesvirus (HVT). The isolates were designated Ala-7, 8, 9, and 10. These 4 MDV strains were compared with the GA isolate of MDV in chickens vaccinated with graded doses of HVT. Challenge with the MDV strains was also with graded doses. All 5 isolates of MDV were similar in virulence. However, protection afforded against MD lesions by HVT was significantly lower in the Ala-7, 8, and 9 isolates than with the Ala-10 or GA isolates. The Ala-7, 8 and 9 isolates of MDV induced small-cell plaques in chick embryo fibroblasts, the Ala-10 isolate induced both large and small cell per plaque types, and the GA isolate produced predominantly small cell plaques with a few plaques of the large cell type.

Animals↗
PubMed1981

B-haplotype influence on Marek's disease, Rous sarcoma, and lymphoid leukosis virus-induced tumors in chickens.

Experiments were conducted to establish whether B-haplotype genes that determine resistance to RSV-induced tumors would also influence resistance to Marek's disease and lymphoid leukosis. Matings of line 6(3) x 15(1) F3 or F4 breeders segregating for the Ea-B locus antigens that are markers for B2 and B5 haplotypes of the B major histocompatibility complex were made to produce B2B2, B2B5, and B5B5 chicks. The chicks were infected with a standard inoculum of one of the three tumor viruses in separate experiments. The B2 haplotype from 6(3) conveyed greater resistance to tumors induced by all three viruses than the B5 from 15(1) chickens. This finding suggests that some gene(s) in the B-haplotype may determine a general ability to resist tumor formation or cause tumor regression.

Animals↗
PubMed1983

Socialization, the sequencing of environmental factors, and their effects on weight gain and disease resistance of chickens.

Weight gain following a 60-hr fast was influenced 1) by prior experiences of either a presence or an absence of a similar initial fast followed by either being moved to unfamiliar quarters or being fed corticosterone or 2) whether or not the chickens were socialized. Socialization, but not the environmental stresses, increased antibody response to erythrocyte antigens and increased resistance to Escherichia coli challenge. Although the experimental cockerels had increased heterophil/lymphocyte ratios following the feeding of corticosterone, their antibody response to erythrocyte antigen and their resistance to E. coli challenge were not altered. The presence or absence of water deprivation stress early in life failed to alter any results.

Animals↗
PubMed1983

Simultaneous vaccination of one-day-old broiler chickens with tenosynovitis virus and turkey herpesvirus.

An attenuated tenosynovitis virus vaccine and turkey herpesvirus (HVT) vaccine mixed prior to vaccination were injected subcutaneously into one-day-old chicks. In laboratory and field trials there did not appear to be any interference, because chickens vaccinated with both vaccines were effectively immunized against challenge with virulent Marek's disease virus or tenosynovitis virus when compared with unvaccinated chickens or chickens vaccinated with either HVT or tenosynovitis virus. The combined tenosynovitis and HVT vaccine had essentially the same virus titers when compared to the titers of each vaccine prior to mixing. Also, the HVT viremia levels and the serum neutralization titers of chickens vaccinated with both vaccines were essentially the same as those in chickens vaccinated with a single vaccine. In field trials, chickens vaccinated with the combined vaccines had fewer condemnations for parts and septicemia-toxemia and total condemnations when compared to chickens not vaccinated with tenosynovitis virus. There was less mortality in the majority of the flocks vaccinated with tenosynovitis virus vaccine and HVT when compared to flocks receiving only HVT vaccine.

Animals↗
PubMed1984

Degenerative myopathy of the Musculus supracoracoideus and production traits in strains of meat-type chickens.

The incidence of degenerative myopathy of the Musculus supracoracoideus (DMS) was calculated in 23 strains comprising 1868 meat-type chickens. Twenty strains were commercial parent stocks and three strains were experimental strains from Ottawa similar to commercial broiler stocks of some 15 to 20 years ago. In the commercial strains DMS incidence ranged from 0 to 43% in males and 0 to 22% in females at ages ranging from 49 to 68 weeks. The three experimental strains did not have DMS. Data from strains with DMS were analyzed for associations between DMS and each of a number of body size and egg production traits. The DMS-positive birds had a larger breast angle (P less than .05) measured at 6 weeks of age (93 vs. 89 degrees) and a larger body weight (P less than .01) at 52 weeks (3748 vs 3594 g) than DMS-free birds. No significant relationships with other body size or egg production traits were detected.

Animals↗
PubMed1984

The ontogeny of blood cells, complement, and immunoglobulins in 3- to 12-week-old 15I5-B congenic white Leghorn chickens.

Six partially developed line 15I5-B congenic White Leghorn chicken strains were used to investigate age and B haplotype effects on hematocrit, total and differential leukocyte counts, hemolytic complement, immunoglobulins, and body weights. The .C-12 line had the lowest hematocrit values throughout the study. The .15I-5 line always had the highest mean hematocrit value and differed from the .C-12 and .P-13 lines at 3, 8, and 12 weeks, as well as lines .N-15 and .6-2 at 12 weeks. Ontogenically, the total leukocyte, hemolytic complement, immunoglobulins, and body weight values increased after 3 weeks in all lines. Lymphocytes were the predominant leukocyte after 3 weeks in all lines studied. At 12 weeks, the .C-12 line had the highest total leukocytes, heterophils, lymphocytes, and monocytes among the lines studied. The .6-2 line had a significantly higher hemolytic complement level than the .P-13 or the .C-12 line at all 3 ages, and at 12 weeks it also differed from the .7-2 line. The lines were found to be comparable for immunoglobulin classes M and G. In this study the line 15I5-B congenic lines differ for the traits of hematocrit and hemolytic complement level, and the results suggest the difference may be determined by genes in the B complex.

Age Factors↗
PubMed1984

Vaccination against Marek's disease and infectious bursal disease. II. Titration and in vivo efficacy of the coinfection-derived bivalent live vaccine for turkey herpesvirus and infectious bursal disease virus.

The bivalent HVT/IBDV live vaccine, developed by cocultivation of the turkey herpesvirus (HVT) and infectious bursal disease virus (IBDV) vaccine in cell cultures, was quantitated. The titer of each constituent virus could be successfully determined in vitro by pretreatment of the vaccine with anti-IBDV serum or chloroform (CHCl3). Studies in vivo further demonstrated that the anti-IBDV serum-treated HVT/IBDV vaccine lost its immunogenicity by failing to induce IBDV-neutralizing antibody or to protect vaccinates from bursal atrophy after challenge exposure to infectious bursal disease. The CHCl3 treatment significantly reduced the efficacy of the vaccine to protect vaccinates against Marek's disease challenge.

Animals↗
PubMed1985

Vaccination against Marek's disease and infectious bursal disease III. Growth rate of both turkey herpesvirus and infectious bursal disease virus in coinfected cell cultures.

Titers of the turkey herpesvirus (HVT) and infectious bursal disease virus (IBDV) in coinfected cell cultures, used to produce a live bivalent HVT/IBDV vaccine, were determined daily. Based on the daily titers, cells harvested either 2 or 3 days after inoculating the second virus (IBDV) into HVT infected cell cultures yielded the maximum titers for both viruses. Harvesting coinfected cell cultures on either day provided the most suitable source of the live HVT/IBDV vaccine against Marek's disease and infectious bursal disease.

Animals↗
PubMed1987

Selection for early responsiveness of chicks to Escherichia coli and Newcastle disease virus.

A broiler chicken population was divergently selected for high or low early immune responses to Escherichia coli and to Newcastle disease virus (NDV) vaccines. Four selection cycles were performed in one replicate, and a single cycle in a second replicate. Selection was based on sire-family averages of a titer index (TI) calculated as the mean titer of antibodies produced by offspring vaccinated with either E. coli or NDV at 18 or 10 days of age, respectively. After the first selection cycle, TI of the early-high (EH) line were 22 and 38% greater than those of the early-low (EL) line in Replicates A and B, respectively. After four selection cycles, the average immune response to E. coli and NDV of Line EH exceeded that of Line EL by 68%. Viability was greater in the EH than in the EL line. Realized family heritabilities were .72 and .67 in Replicates A and B, respectively and the levels of response to the two antigens were not genetically correlated. The immune response of the EH line developed earlier than that in the EL line as shown by fewer nonresponders against E. coli and the higher response of this line against the two antigens at young ages. Mortality after challenge at 18 days of age and general mortality from hatching to 20 wk of age was lower in Line EH than in Line EL. Body weights at 7 wk were higher in EH than EL chicks.

Animals↗
PubMed1989

Efficacy of simultaneous administration of Marek's disease and viral tenosynovitis vaccines to day-old broiler chickens.

Experiments were conducted to determine the efficacy of simultaneous administration at 1 day of age of the herpes virus of turkeys vaccine (HVT) and viral tenosynovitis (VT) vaccine. Day-old broilers from commercial breeders, which were immunized against both MD and VT, were used. The vaccines were injected at full dosage or diluted 1 to 4. Challenge with either Marek's disease virus (MDV; intraperitoneal) or VT virus (footpad) was at 7 days of age. At 7 wk of age, birds were weighed, killed, and examined for gross lesions. Either vaccine given at full dosage alone, or in combination, rendered birds resistant to homologous viral challenge. However, when either vaccine was diluted and administered alone, the efficacy of the VT but not the HVT vaccine was reduced, resulting in increased lesions and mortality and decreased weight gain after VT challenge. When the HVT vaccine was diluted and combined with undiluted VT vaccine, interference occurred, resulting in reduced efficacy of the HVT vaccine (increased tumors and mortality and reduced body weight). In contrast, combining the HVT at full dosage and the diluted VT vaccine given alone. The data indicate that caution should be maintained when mixing HVT and VT vaccines. For maximum efficacy, both vaccines should be mixed undiluted when administered simultaneously.

Analysis of Variance↗