Interaction of aflatoxin in the feed and immunization against selected infectious diseases in poultry. II. Effect on one-day-old layer chicks simultaneously vaccinated against Newcastle disease, infectious bronchitis and infectious bursal disease.

A study was conducted to assess the effects of aflatoxin contaminated feed on the immunoresponse of one-day old layer chicks to attenuated live virus vaccines for Newcastle disease (ND), infectious bronchitis (IB) and infectious bursal disease (IBD). Concurrent exposure of chickens to 2tiO parts per billion (ppb) aflatoxin in feed and vaccination against ND, IB and IBD resulted in lack of adequate protection against subsequent experimental challenge, as assessed by antibody responses compared to chickens fed aflatoxin-free ration. The mortalities were higher in chickens fed 200 ppb of aflatoxin than in chickens fed on aflatoxin-free ration.

Aflatoxin and immunity in layer hens.

A study was conducted on the impact of aflatoxin in the feed on the prophylactic immunization of layer hens against Newcastle disease, infectious bronchitis, infectious bursal disease and fowl cholera. Four-hundred-and-eighty 18-week-old white leghorn chickens were used. Different groups of hens were vaccinated, as per commercial recommendations, with a commercial inactivated triple vaccine against Newcastle disease, infectious bronchitis, and infectious bursal disease. A killed polyvalent bacterin was used for fowl cholera. Aflatoxin was fed for 22 weeks at a daily dose of 200 parts/10(9)/hen. Aflatoxin significantly reduced antibody titres, resulted in a decrease of egg weight, a decrease in egg production and an increase of mortality rate in challenged hens. Aflatoxin was detected in eggs at levels far above the permissible concentration.

Interaction of aflatoxin in the feed and immunization against selected infectious diseases. I. Infectious bursal disease.

A study was conducted on the impact of aflatoxin in the feed on immunization against infectious bursal disease (IBD) in chickens using an attenuated live vaccine. Three-hundred-and-ninety broiler chicks were used. The aflatoxin feeding of 100 and 200 parts/10(9) of AFBI started when chicks were 10 days old and continued for 8 weeks. An attenuated live IBD virus vaccine was administered in drinking water at 2 and 5 weeks of age. A field IBD virus strain was used for challenge. The antibody titres, bursal indices, bursal lymphocyte counts and feed conversion ratios were monitored. The impact of aflatoxin on reduced body weights and lower antibody titres was shown to be highly significant (P<0.0001).

Reference values for functional residual capacity and maximal expiratory flow in young children.

To determine the relation of functional residual capacity and maximal expiratory flow at functional residual capacity to sex, age, height, and weight in healthy young children living in Portland, Oregon, we tested 37 boys and 36 girls using a modified helium-dilution technique and partial expiratory flow-volume curves. Within the age, height, and weight ranges studied, exponential or multiple regression techniques offered no substantial advantage over simple linear regression using height, weight, or age. There were no sex differences for the relationship between either variable and age, height, or weight. These techniques can readily be used in children as young as 3 years of age and may provide a method for studying lung growth and development in early childhood and a way to observe the progression of disease or the effect of treatment in the young child.

Pulmonary function in young children with alpha 1-antitrypsin deficiency: comparison with matched control subjects.

In this paper we report the initial cross-sectional data from a prospective study of pulmonary function in children with moderately severe and severe alpha 1-antitrypsin deficiency. Using a case-control design, our cases were 19 children 3 to 7 years of age with alpha 1-antitrypsin deficiency, Pi phenotype ZZ or SZ. Control subjects were selected from healthy children participating in a study to establish reference values for functional residual capacity and maximal expiratory flow at functional residual capacity, using a 1:1 match for sex, height, age, and weight. We found no significant difference between the cases and their matched control subjects with respect to functional residual capacity and maximal expiratory flow at functional residual capacity. We conclude that through 7 years of age there is no gross impairment in overall pulmonary function in children with moderately severe and severe alpha 1-antitrypsin deficiency, Pi phenotypes ZZ and SZ.