Effect of feeding cholesterol and fat supplemented diets was studied on cholesterol contents of follicular yolk and egg yolk of quails of 3 different age groups i.e. 5-week-old, 12-week-old and 1-year-old. Five different dietary combinations were fed to different groups for 30 days. The diets were control diet, normal diet without fish-meal, control diet with 1% cholesterol, control diet with 10% lard, and control diet with 1% cholesterol and 10% lard. Different dietary treatments affected both the follicular and egg yolk cholesterol levels in all the treated birds. The cholesterol levels were higher in 1-year-old birds irrespective of the dietary treatments. The dietary treatment affected the cholesterol level of F1 follicular yolk of 12-week-old the least as compared to 5-weeks old or 1-year-old laying quails.

Intestinal glucose uptake was measured in vivo using ligated upper ileum in high, medium and non-laying RIR birds. The biochemical changes in blood and absorbing cells of intestine of these birds were also studied. Significantly higher glucose absorption by the intestine was observed in the birds, laying either 50% (medium) or no eggs (non-layer). Significant increase in the activity of alkaline phosphatase in the mucosal homogenates, prepared from the non-ligated ileum, was observed in these groups also. No significant difference in egg-yolk cholesterol was observed between medium and high laying birds although there was a sharp increase, in plasma cholesterol level in non-layers which declined in the egg-producing birds. Rate of lay did not change the plasma glucose concentration though higher plasma protein concentrations were found in high producing birds.

Daily administration of cadmium salt for 25 days (2.5 mg per Kg body weight) in the male domestic fowl caused the end of treatment period. An increased incidences of concentration. Fertility dropped to zero at the end of the treatment period. Activity of acid and alkaline phosphomonoesterases were also drastically reduced by the end of treatment period. An increased incidences of morphological abnormalities of spermatozoa were noticed in the treated birds. After 46 days cessation of the treatment, full recovery of the above measures was found. These alterations suggest the reversible type of effect of cadmium chloride on the spermatozoa of male domestic fowl.

Angiotensin-converting enzyme (ACE) activity has been determined in the semen of certain avian and mammalian species as well as its release during cold shock. The maximum and minimum levels of this enzyme were found in mammalian spermatozoa and in seminal plasma, respectively. It was found that ACE activity in mammalian spermatozoa was more pronounced than in the seminal plasma, whereas in the avian species a revers pattern was observed. However, there were no significant differences in ACE activity in spermatozoa and seminal plasma between layer and broiler strains of avian species. By contrast, ACE activity in the spermatozoa and seminal plasma of buffalo bulls was significantly higher (P/0.01) than in cattle bulls. Cold shock did not significantly alter semen characteristics in avian species, while a significant (P/0.01) decrease in sperm live counts and motility as well as a corresponding increase in morphological abnormalities were observed in the spermatozoa of cattle and buffalo bulls due to cold shock.

At peak of summer (June), catecholamines were determined in the yolk of fresh egg of White Leghorn hens laying either below 40% or above 70% maintained in an individual cages under uncovered asbestos cement roof or similar type of roof with sprinkler system put in service for 30 min from 2.00 to 2.30 PM daily or similar roof but fully covered with green vegetations. The maximum ambient temperature ranged from 36-degrees to 41-degrees-C and minimum 21-degrees to 29-degrees-C. Epinephrine in yolk showed a clear cut increase in poor layers as compared to good layers irrespective of housing system while nor-epinephrine concentration remained higher in good layers as compared to poor but dopamine did not show any specific trend. Dopamine, nor-epinephrine or epinephrine concentrations did not vary due to different housing system. Total catecholamines, however, remained significantly lower in the yolk of eggs collected from sheds covered with green vegetation. The rectal temperature was not influenced significantly due to housing OT productiOn StatUS. It was concluded that a hen that possess lower concentration of epinephrine in egg yolk, has better potential to lay during heat stress.

Each of 20 White Leghorn hens of 13 to 14 weeks were subjected to partial sinistral ovariectomy and sham-operations. In half of the hens from each group, the percentage of egg production and clutch size were noted until 50 weeks of age. The growing pattern of normal ovarian follicles was also recorded at 26 weeks of age in a rest half of the hens in the two groups. The percentage of egg production and the mean and variance of clutch size did not differ significantly (P < 0.05) between the partially ovariectomized and sham-operated groups. The growing yellow follicles (> 8 mm) in the rapidly developing phase in these two groups did not vary, although the smaller follicles (4 to 8 mm in diameter) remained significantly (P < 0.01) more in the sham-operated control group than in the partially ovariectomized group. This observation indicates that smaller follicles (4 to 8 mm) developed in the larger (> 8 mm) follicles more efficiently in partially ovariectomized hens than in the sham-operated (control) hens.In a second experiment, one group of hens had all the yellow follicles (> 8 mm) removed, while a second group of hens was left untreated. On the 3rd and 6th day post treatment, the hens were examined for the presence of ovarian follicles. No significant (P < 0.05) difference in the growing pattern of subsequent follicles (2 to 4 or 4 to 8 mm) was detected due to treatment.These data demonstrate that the mechanisms that regulate follicular growth and atresia are adjust to maintain normal ovulation following partial ovariectomy.

1. The presence of histamine in egg yolk, its losses during storage, incubation and heating, and its relationship to cage density stress and the egg production status of hens are described.2. A significant (P < 0.05) reduction in the histamine concentration of egg yolk was noted after incubating or heating egg yolks or on storage eggs.3. Histamine concentration was greater in the yolks of high egg producing hens.4. The concentrations of histamine in egg yolks did not change significantly (P < 0.05) on keeping the hens individually in a cage, pairing them in the same size cage or after separating them again to individual cages.

Different feeding schedules with normal (animal protein) and test (all vegetable protein) diets were practiced in White Rock chicks. The feeding schedules were: daily feeding with normal diet, daily feeding with test diet; alternate day feeding with normal and test diets and 2 consecutive days feeding with normal diet followed by 2 days with test diet.Alternate day feeding with normal and test diets reduced (P < 0.01) the body-weight gain. Test diet reduced (P < 0.01) the plasma protein level. None of the dietary regimens changed the blood cholesterol level and acidphosphatase activity. Daily feeding with test diet and 2 consecutive days feeding with normal diet followed by test diets increased (P < 0.01) blood glucose level. All vegetable protein diet increased (P < 0.01) the alkaline-phosphatase activity in blood. However, test diet and alternate day feeding with test and normal diets increased (P < 0.01) aspartate aminotransferase activity in the blood.

The study was conducted to understand the mechanism of action of corticosterone, a major stress hormone in birds, in suppressing the ovarian activity and to search for remedial approach to check the drop in egg production under stressful conditions. Corticosterone was administered (i/m) in a single dose at the levels of 1, 2 or 4 mg/kg body weight after first oviposition of the sequence at the age of 22 to 26 or 35 to 40 or around 60 weeks in White Leghorn hens. Corticosterone delayed the oviposition in general and higher amount was needed to delay at peak laying stage (35 to 40 weeks). The interruption in ovulation was maximum in the largest ovarian follicle (F1) followed by next largest (F2) and none thereafter. In second experiment corticosterone (4mg/kg bw) alone or after giving alpha-methyl-p-tyrosine (40 mg/hen, catecholamine synthesis blocker) or oestrogen (250 mg/kg) or tamoxifen (1 mg/kg, oestrogen synthesis blocker) was injected in hens (35 to 40 weeks) under similar conditions as in experiment 1. The delay in oviposition induced by corticosterone was prevented only by alpha-methyl-p-tyrosine. In experiment3 the treatments remained the same as in experiment 2 except that these were repeated for 6 days at a lower dose of corticosterone (2 mg/kg bw). The deleterious effect left by corticosterone on egg production was blocked only by alpha-methyl-p-tyrosine. It is suggested that corticosterone may mediate its adverse effect on reproductive functioning through catecholamines.