the aim of this study was to compare the effects of three antibiotic alternatives with a control (antibiotic-free) and an antibiotic diet on performance and gut morphology of broilers reared on litter. 600 day-old ross-308 chicks were assigned to 48 pens in a crd design with 6 × 2 factorial arrangements, in which 2 levels of chick density (5 and 7.5 chicks/m2) and 6 experimental diets (control,...

A technique appropriate to investigation of the developmental fates of distinct embryonic cell types is described and the fate of a particular type of chick myoblast (CMR-I) examined. CMR-I myoblast clones are morphologically different from other chick myoblast clone types and can readily be identified in living cultures. After two weeks of culture CMR-I myoblast clones were collected, aggregat...

Chick-mouse heterokaryons were obtained by UV-Sendai virus-induced fusion of chick erythrocytes with thymidine (dT) kinase-deficient mouse fibroblast [LM(TK(-))] cells. Autoradiographic studies demonstrated that 1 day after fusion, [(3)H]dT was incorporated into both red blood cell and LM(TK(-)) nuclei of 23% of the heterokaryons. Self-fused LM(TK(-)) cells failed to incorporate [(3)H]dT into n...

In mammals, facial branchiomotor (FBM) neurones are born in ventral rhombomere (r) 4 and migrate through r5 to dorsal r6 where they form the facial motor nucleus. This pattern of migration gives rise to the distinctive appearance of the internal genu of the facial nerve, which is lacking in birds. To distinguish between extrinsic cues and intrinsic factors in the caudal migration of FBM neurone...

Transcriptionally inactive chick erythrocyte nuclei were reactivated by Sendal virusinduced fusion of erythrocytes with rat L6J1 myoblasts. We used antibodies to trace the appearance of a specific protein engaged in transcription of a defined class of genes, those coding for rRNA, during reactivation. Using immunofluorescence microscopy, we found increasing amounts of rat RNA polymerase I to ap...

The distribution and behavior of chick primordial germ cells (PGC) injected into quail embryos were examined. PGC from chick embryos at stages 13-14 were injected into the blood stream of quail embryos at stages 15-20. After one day, the quail embryos were examined histologically. The chick PGC in the quail embryos could be readily identified by the histochemical PAS technique, whereas quail PG...

Ott (1, 2) has shown that desoxypyridoxine (2,4-dimethyl-3-hydroxy5hydroxymethylpyridine) and methoxypyridoxine (2-methyl-3-hydroxy4-methoxymethyl-5-hydroxymethylpyridine), analogues of pyridoxine, act as pyridoxine antagonists in the chick. Because of our interest in the effects of metabolic antagonists on the development of the chick embryo (3), and on the behavior of mouse tumors growing on ...

This study aims to determine the effect of in-ovo injection L-arginine into local chicken eggs on embryo development and chick performance chicken. A total 160 were incubated using semi-automatic incubator with temperature 37-38C relative humidity 55-65%. The injected solution has a concentration 0.5% (m/v). In treatment was divided 4 groups, first without (control), second 0.2 mL (m/v)/egg, th...