Inherited 7S immunoglobulin deficiency of chickens is associated with bursal degeneration anomalies.

Partially inbred line UCD 140 chickens develop an age dependent inherited 7S immunoglobulin deficiency with features similar to acquired human agammaglobulinemia. Serial and developmental observations in line UCD 140 and control lines 440 and 444 reveal a significant progressive premature involution of the bursa of Fabricius. These bursal changes are characterized by epithelial and medullary degeneration, reduced follicular bursacyte mitosis, and decreased follicular plasma cells. These abnormalities have not been previously described in other avian systems and suggest that this immune deficiency is due to a primary bursal disease.

Tolerance, viral shedding, and neoplasia in chickens infected with non-defective reticuloendotheliosis viruses.

Chickens inoculated as embryos with non-defective reticuloendotheliosis viruses (ndREVs) generally developed a "tolerant" infection characterized by lack of immunofluorescent antibody and by a viremia that persisted through 93 weeks. Chickens inoculated at hatching generally developed a "non-tolerant" infection characterized by antibody development that gradually waned as the chickens aged and by a transient or intermittent viremia. Although chickens tolerantly infected with ndREV strain T were immunodepressed, tolerance to ndREVs did not depend on immunodepression, because 17-to-20-week-old chickens tolerantly infected with ndREV strain CS were normal in antibody response to sheep red blood cells and Brucella abortus and in mitogen-stimulated blastogenesis of blood lymphocytes. Tolerantly infected dams shed low levels of gs antigen and virus into eggs at high frequencies; however, in two trials, congenital transmission of virus by strain-CS-infected dams was documented in only 2 of 42 and 1 of 132 progeny chicks. Eggs and progeny chicks from non-tolerantly infected dams were always negative for virus and gs antigen. After long latent period (17 to 93 weeks), ndREV-infected chickens developed lymphomas involving the bursa of Fabricius and other visceral organs at high frequency and developed sarcomas, carcinomas, and inflammatory nerve lesions at a lower frequency. The ability of ndREVs to induce tolerant and non-tolerant infection, virus- and antigen-shedding into eggs, and chronic neoplastic disease resembled that of lymphoid leukosis virus, another common avian retrovirus. Certain differences in epidemiological properties of these 2 viruses are discussed.

Concurrent infections of cecal trematodes, Zygocotyle lunata, and Notocotylus sp., in the domestic chick and observations on host-parasite relationships of Notocotylus sp.

Single and concurrent infections of cecal trematodes, Zygocotyle lunata and Notocotylus sp., were studied in controlled, laboratory infections in the domestic chick. The recovery of Notocotylus sp. from the chick cecum was reduced significantly in the presence of Zygocotyle lunata. Neither the size nor the distribution of either helminth was affected by the presence of the other. The ventral surface of Notocotylus sp. was associated intimately with the cecal villus, and this fluke fed on host blood.

Relationship between Eimeria adenoeides infection and aflatoxicosis in turkey poults.

Three-week-old turkey poults receiving 250 micrograms/kg of dietary aflatoxin displayed prolonged prothrombin times due to decreased fibrinogen levels and depressed activity of factor II. Decreased body weights and increased mortality were also evident. Poults experiencing an Eimeria adenoeides infection had slightly increased prothrombin times that were not corrected by the addition of specific clotting factors. These birds exhibited significant reductions in total plasma protein levels. The combination of E. adenoeides and aflatoxicosis resulted in a significant depression in body weight, altered prothrombin time, and decreased levels of plasma calcium, protein, and fibrinogen. Increased mortality was also observed. E. adenoeides did not affect the hemostatic system of the turkey as severely as does aflatoxin. Turkeys were shown to be highly susceptible to aflatoxin when compared to chickens.

Hereditary uricemia and articular gout in chickens.

Ten generations of selection for uricemia and articular gout have led to the development of the HUA line which is characterized by a threefold increase in plasma level of uric acid when compared to the control LUA line, even when fed diets containing normal levels of protein. Articular gout results in many cases, especially among adult males fed a normal breeder diet. Restriction protein level of the diet delays or prevents the development of articular gout in mature males of the HUA line. The data suggest that relatively few genes are responsible for the defect in renal transport of uric acid which underlies the uricemia and gout. The association of lower levels of uric acid with dominant white plumage color suggests a linkage of a major recessive gene for the I gene. Ambient temperature, because of its effect on food consumption, influences the level of uric acid in blood plasma. The HUA line and its control (LUA line), both sex-linked dwarfs, would appear to provide an excellent animal model for the experimental study of gout in man.

[The effect of Mycoplasma synoviae infection on the state of health and results of fattening of broiler chickens compared with the effects of various virus infections. A field study (author's transl)]. / Een praktijkonderzoek betreffende het effect van Mycoplasma synoviae-infectie ten opzichte van de invloed van diverse virus-infecties op de gezondheidstoestand en de mestresultaten van slachtkuikens.

Field studies in 160 flocks of broiler chickens in two areas in the Netherlands showed that Mycoplasma synoviae infection, the presence of which was detected by serological testing in 17.5 per cent, had only a slight adverse effect on the results of fattening. Mycoplasma synoviae as well as IB infections were found to be more common in flocks affected with colibacillosis and/or in which higher proportions of birds were condemned because of polyserositis. Infectious bursal disease, IB and CELO virus infections are very common particularly in the southern areas of the Netherlands, and have a significantly adverse effect on the results of fattening. The findings suggest that vaccination against IB and Gumboro disease often fails in flocks in areas showing a high incidence of infection.