This experiment was carried out using 800 Japanese quail eggs to study the hatch performance of different eggs weight as affected by light pulses during incubation. Incubating eggs comprising of small (10.5g), medium (10.5-11.5g) and large (>11.5g) weight categories incubated under the recommended conditions of the quail eggs with light pulses or without. The obtained results showed insignificant differences among eggs size groups for late dead embryo, dead in shell, chemical composition of embryo and chick quality scores. However, highly significant differences in hatchability, early dead embryo, piped egg, egg weight loss, embryo weight percentages, hatch time and chick weight or weight loss. In regard to the effect of light pulses, it affected hatchability, embryo growth and moisture content of embryo. However it is not significant differences in dead embryo, dead in shell, egg weight loss, hatch time, chick weight or weight loss, chick quality scores. Insignificant interactions of incubated light pulses × egg weight groups were existed in most studied traits. It could be concluded that the suitable results of hatchability and hatch performance were obtained for medium sized eggs of Japanese quail with incubated light pulses.

The current study was conducted to investigate pre and post hatch performance of 800 Japanese quail eggs stored and incubated under different light conditions. All eggs were randomly distributed into four groups, stored for 7 days and then incubated under the recommended conditions with or without lighting as follows: The first group (control, C) was stored and incubated under dark conditions (0L:24D), The second groups (T1) was stored under dark conditions (0L:24D) and incubated under continuous light conditions (24L:0D). The third group (T2) was stored under continuous light (24L:0D) and incubated under dark conditions (0L:24D). The fourth group (T2) was stored and incubated under continuous light (24L:0D). The results showed that the effect of light treatments during storage and incubation periods on embryonic weight was significant (P≤0.05) at 6, 10 and 12 days of incubation, hatchability and live pipped. However, early and late death embryo, dead in shell, moisture and fat content of the embryos were not change between treatments. Egg weight loss percentage was significantly (P≤0.05) higher in eggs subjected to T3 (15.92%) followed by T1 (15.66%) then T2 (15.51%) and control (14.11%) groups. Chick weight at hatch was significantly (P≤0.05) heavier in group of eggs exposed to continuous lighting during storage and incubation periods (T3; 7.99 g) than eggs of groups T1 (7.60 g), T2 (7.04 g) and control group (6.98 g). Lighting treatments did not affect significantly each of chick weight loss (%) and chick quality (%). Birds produced from eggs exposed to light during incubation period had significant higher (P≤0.05) daily gain (3.82g/day). Also, the feed conversion for growth of birds produced from eggs exposed to light during storage and incubation periods (T1 and T3) was significantly (P≤0.05) improved (3.92 and 3.94 g feed/ g gain, respectively) than those produced from dark conditions (C and T2). However no significant differences in egg mass and feed conversion during egg production period were found among all groups. It could be concluded that exposing eggs of Japanese quail to lighting during incubation only or/and storage and incubation leads to an improvement in each of embryonic development, hatching performance and post hatching performance.

In this study, the light flashes program was used for raising growing rabbits during summer season under hot climatic conditions of Upper Egypt. Seventy two growing New Zealand white rabbits, six weeks old, were randomly divided into three experimental groups (24 rabbit/group): Group 1, the rabbits were subjected to 12 h constant light/day and was considered as a control (C); Group 2 (T1), the rabbits were subjected to 12 h light (6 h constant light and 6 h light flashes); Group 3 (T2), the rabbits were subjected to 12 h light flashes/day. Rabbits were reared under the same managerial, feeding and hygienic conditions throughout the experimental period. Besides, body weight (BW), body weight gains (BWG), feed intake (FI), feed conversion (FC), carcass traits, blood parameters and economical efficiency were estimated in this study. The achieved results confirmed that the productive traits (BW, BWG, FI and FCR) and economical efficiency of New Zealand white rabbits during the summer were better in the light flashes than in the constant light. It is worth to mention that AST, ALT, N / L Ratio, rectal temperature and mortality rate were significantly lower in light flashes than in constant light. Furthermore, lymphocyte, hematocrit, albumin and glucose increased relatively in light flashes groups. While, no significant differences were existed in blood protein, lipids, globulin, cholesterol and carcass traits percentages. Generally, it could be concluded that using light flashes in small and large farms owing to its beneficial effects on the productive traits of growing rabbits as well as lowering of electricity consumption which are considered of low cost, when compared with the costs constant light.

The present work aimed to study the effect of light flashes on the growth performance, carcass characteristics, gonads, chemical composition and economical efficiency of New Zealand white rabbits. Seventy two rabbits aged 8 weeks were randomly divided into three experimental groups (24 rabbit each): The rabbits in control group (C) were exposed to constant light (12 h Light: 12 h Dark). In the other treated two groups, the 12 h of daylight period was divided into 6 h (constant light) and 6 h (flashes of light) for either 15 min. / h (T1) or 30 min. / h (T2). Exposure of young rabbits to flashes of light affected many of the studied traits and the effects were significant on body weight, weight gain, feed intake, feed conversion, gonads, body temperature, dressed carcass and chemical composition percentages. While, there are insignificant differences in meat protein and carcass cut-up parts percentages. It concluded that the most suitable lighting program for rearing rabbits is the flashes of light (15 min/hour), because it was more economically efficient than continuous or flashes of light (30 min/hour).

Seven hundred and twenty, four weeks old Dandarawi chicks were used to study the effects of light source on their productive and reproductive performance. Chicks were divided into 3 equal groups (240 birds each) and housed in floor pens. The first group was used as control and reared under incandescent light bulbs (IL), while the second and third groups were reared under fluorescent (FL) and saving light bulbs (SL), respectively. All birds were raised under photoperiod of 12 and 16 hours per day during the growing and laying periods, with light intensities of 5-10 and 10-25 Luxes, respectively. Feed and water were available ad lib. and all the other conditions were the same during the experimental period. Results showed that birds reared under SL and FL bulbs had significantly (P≤0.05) higher body weight (BW), daily weight gain (BWG), egg yolk index, liver and giblets percentages than the control group. Also, egg shell thickness of birds reared under SL bulbs significantly increased (P≤0.05) compared to birds reared under FL and IL bulbs. In addition, birds reared under IL bulbs had significantly (P≤0.05) higher egg number, hen day production (HDP) and ovary percentages as compared to the other two groups. No significant differences (P≤0.05) were found between groups in leg problems, carcass traits, testes percentage, egg weight and fertility and hatchability. Finally, the economical efficiency of the birds reared under SL and FL bulbs was better than the IL groups during the growing period by 26.4 and 36.1%, respectively. However, the economical efficiency of the birds reared under IL light bulbs was better than the FL and SL groups during laying period by 12.1 and 9.9% as well as by 2.3 and 1.5% for table and fertile eggs, respectively.

Seven hundred and twenty, four weeks old Dandarawi chicks were used to study the effects of light source on their productive and reproductive performance. Chicks were divided into 3 equal groups (240 birds each) and housed in floor pens. The first group was used as control and reared under incandescent light bulbs (IL), while the second and third groups were reared under fluorescent (FL) and saving light bulbs (SL), respectively. All birds were raised under photoperiod of 12 and 16 hours per day during the growing and laying periods, with light intensities of 5-10 and 10-25 Luxes, respectively. Feed and water were available ad lib. and all the other conditions were the same during the experimental period. Results showed that birds reared under SL and FL bulbs had significantly (P≤0.05) higher body weight (BW), daily weight gain (BWG), egg yolk index, liver and giblets percentages than the control group. Also, egg shell thickness of birds reared under SL bulbs significantly increased (P≤0.05) compared to birds reared under FL and IL bulbs. In addition, birds reared under IL bulbs had significantly (P≤0.05) higher egg number, hen day production (HDP) and ovary percentages as compared to the other two groups. No significant differences (P≤0.05) were found between groups in leg problems, carcass traits, testes percentage, egg weight and fertility and hatchability. Finally, the economical efficiency of the birds reared under SL and FL bulbs was better than the IL groups during the growing period by 26.4 and 36.1%, respectively. However, the economical efficiency of the birds reared under IL light bulbs was better than the FL and SL groups during laying period by 12.1 and 9.9% as well as by 2.3 and 1.5% for table and fertile eggs, respectively.

This study was conducted to investigate the effects of lighting and feeding time management (at morning or afternoon) on productive and reproductive performance of Japanese quail in the hot summer of Assiut. Two hundred and forty unsexed one-day old chicks were reared in batteries and assigned to 4 groups (60 birds /each). The birds of first and second groups (C and T1), were exposed to light at the morning (1000 to 2200) and fed twice daily at 1000 and 1600 h as well as 2200 and 0400 h, respectively. The third and fourth groups (T2 and T3) were exposed to light at the afternoon (2200 to 1000) and fed twice daily at 1000 and 1600 h as well as at 2200 and 0400 h, respectively. All the other conditions were the same during the experimental period. Birds were supplied with clean water all the time. The results showed that change feeding and lighting time to afternoon significantly (P≤0.05) improved growth performance, body temperature, egg number, egg quality and fertility percentage. While, no significant differences (P≤0.05) existed in hatchability, egg weight and egg components. In conclusion, feeding Japanese quail at afternoon coincide with light is a good and economical managerial tool to alleviate the harmful effects of high temperature stress during the summer season at Assuit.