Reoviruses are important pathogens responsible for poor growth performance and silent losses in the poultry industry. They are associated with many disease and syndromes such as malabsorption (runting and stunting syndrome), respiratory diseases and immunosuppression. Broiler birds are most susceptible to viral infections during the early post hatching period. Therefore, the transfer of materna...

Published data on 4-week-long administration of extra thyroxine (T4) in broiler breeder hens to alleviate the cold-induced ascites in their offspring suggested that long-term maternal hyperthyroidism would affect the gastrointestinal tract morphology. Broiler breeder hens (n=70) were reared in individual cages and allotted to control and hyperthyroid groups (five replicates of seven ...

The present study was conducted to investigate the effects of four different levels of dietary probiotic (protexin) on productive traits and egg quality of broiler breeder hens. One hundred sixty female 64-week-old broiler breeders (Hubbard classic) were involved in this experiment. The birds were randomly assigned to control Group A (unsupplemented diet), Group B (0.25% protexin supplemented d...

A study was conducted to examine the effect of yeast culture residue (YCR) on the suppression of aflatoxicosis in broiler breeder hens. One hundred twenty, 35-wk-old, Cobb broiler breeder hens of the same cross were fed diets supplemented with aflatoxin (AF) (0 or 3 mg/kg) and YCR (0 or 2 lb/ton) singly and combined in a 2 × 2 factorial designed experiment. The birds were randomly assigned to p...

avian influenza is an important disease of poultry with the potential to cause major epidemics resulting in significant economic losses. the presence of avian influenza viruses (aiv) in chickens in iran has not been previously reported. an avian influenza outbreak in broiler, layer and breeder farms occurred during a very hot summer in july 1998. three aiv isolates designated as 101, 102 and 10...

The effects of environmental temperature (ET) and dietary ME on core body temperature (CBT) and production efficiency were evaluated in broiler breeder hens. A total of 192 Ross 708 broiler breeder hens were individually caged in one of 6 temperature-controlled chambers (32/room) at 20 wk of age. A biotelemetry sensor was surgically implanted abdominally to measure CBT of 8 birds/tmt every 10 m...

The pharmacokinetics of levamisole was studied in 20 broiler breeder chickens (chickens that give eggs to breed broilers). A single dose of levamisole (40 mg/kg) was administered orally or intravenously to chickens before the onset of egg production, prelay (age = 22 weeks), and repeated at the peak of egg production (age = 32 weeks). A high-pressure liquid chromatographic with ultraviolet dete...

Uniform growth is a desirable trait in all large-scale animal production systems because it simplifies animal management and increases profitability. In parental broiler flocks, so-called broiler breeders, low growth uniformity is largely attributed to the feed competition that arises from quantitatively restricted feeding. As feed restriction is crucial to maintaining healthy and fertile breed...

In size-structured groups, conflict over rank, resources or access to breeding opportunities is expected to be greatest among individuals that are similar in size. We tested this general prediction using the cooperatively breeding African cichlid, Neolamprologus pulcher. We predicted that, when size differences between group members were small, we would observe some or all of: increased aggress...

Unabsorbed yolk sacs are being investigated as a possible reservoir for internal Campylobacter and salmonellae contamination of processed poultry carcasses. However, it is unknown at what frequency that unabsorbed yolk sacs persist at the time of processing of broilers and spent breeders. Seven sets of 100 broiler carcasses (at 6 or 8 wk of age) were obtained from commercial processing plants. ...