Previously, we have measured daily changes (developmental patterns) in embryonic heart rate (fh) in altricial and semi-altricial (ASA) birds (range of mean fresh egg mass approximately 1-20 g), semi-precocial seabirds (egg mass approximately 38-288 g) and precocial birds (egg mass approximately 6-1400 g). An allometric relationship between embryonic fh at 80 % of incubation duration (ID) and fr...

We examined whether the previously reported low cost of embryonic development in pelicans could be attributed to a more efficient conversion of egg energy to hatchling tissues as a result of high initial egg water content, low embryonic metabolic rate and growth later in incubation than in more precocious species. We therefore determined egg and hatchling composition and the development of embr...

The present study aimed at evaluating the effect of the dietary inclusion of organic trace minerals selenium and zinc on the performance and internal and external egg quality of Japanese quails submitted to heat stress. Data on egg production, feed conversion (kg feed intake/ kg eggs and dozen eggs), egg weight, egg specific gravity, eggshell thickness and weight, Haugh unit, yolk index, albume...

An experiment was conducted with 72 Bovans Brown laying hens to determine the effect of dietary crude glycerin on laying performance; egg quality; retention of N, Ca, and P; and metabolizability of energy. The dietary treatments consisted of a control corn-soybean diet containing 6% corn starch (17% CP, 2,775 kcal/kg of AME(n), 0.81% lysine, 0.36% methionine, 3.60% Ca, and 0.37% available P) an...

1. In a study spanning two breeding seasons, we assessed the effect of different dietary energy and protein levels on body mass, body condition, and egg production of female ostriches. 2. During the first breeding season, groups were given diets with energy concentrations of 8.5, 9.5 and 10.5 MJ/kg dry mass (DM) metabolisable energy (ME) and protein concentrations of 135, 150 and 165 g/kg. In t...

The substitution effect of noug (Guzoitia abyssinica) seed cake with samma (Urtica simensis) leaf meal (SLM) was investigated on egg production and egg quality parameters in commercial layer hens. Five treatment (T) diets were formulated to contain SLM at 0% (T1), 3% (T2), 6% (T3), 9% (T4) and 12% (T5) by substituting noug seed cake. One-hundred fifty Isa Brown layer pullets w...

The eVect of the number of simultaneously ovipositing females on progeny sex ratio of three Homalodisca coagulata egg parasitoids, Gonatocerus ashmeadi, G. triguttatus, and G. fasciatus was investigated in the laboratory. When one female Gonatocerus parasitoid was present, progeny production was strongly female biased producing »1 male:8 females, 1:14 and 1:9 for G. ashmeadi, G. triguttatus and...

The study was conducted to determine the effects of turkey (Meleagris gallopavo)egg weight on certain egg traits and hatching performance. A total of 178 turkey eggs comprising of three different egg weight groups below 60 g (G I), 61 to 69 g (G II) and above 70 g (G III) were used for this study. Average egg weight (g), egg length (cm), egg breadth (cm) and egg volume (cm3) values increased wi...

the study was conducted to determine the effects of turkey (meleagris gallopavo)egg weight on certain egg traits and hatching performance. a total of 178 turkey eggs comprising of three different egg weight groups below 60 g (g i), 61 to 69 g (g ii) and above 70 g (g iii) were used for this study. average egg weight (g), egg length (cm), egg breadth (cm) and egg volume (cm3) values increased wi...