This study was conducted to examine the present productive potentials of field Desi chickens housed under deep litter system. For this purpose a detailed survey was conducted in rural areas of Punjab Province (Pakistan) to know availability of true specimens of Desi birds. After the survey a total number of 1329 adult Desi birds were selected from different villages of Mianwali and Bhakkar districts. The birds were housed at Govt. Poultry Farm, Mianwali for initial acclimatization for 6 to 8 weeks and subjected then to prophylactic vaccination and then they were shifted to Breeding and Incubation Division of Poultry Research Institute, Rawalpindi. A total number of 450 Desi birds (150 each of black, dark brown and light brown varieties) were randomly selected and were sub-divided into 3 groups of equal size. They were maintained on littered floor in 9 separate pens under optimal managemental conditions for a period of 42 weeks. The results indicated that black, dark brown and light brown groups of Desi chickens produced 1.93, 1.96 and 2.17 dozen eggs (0.0459, 0.0467 and 0.0516 dozen eggs per week) with intake of 29.75, 29.29 and 29.64 kg feed, respectively. The results showed similar performance in egg production and feed intake of different groups of Desi chickens. A similar pattern in egg weight, egg mass and FCR (feed/kg eggs) was observed, however, FCR in light brown Desi (13.68) was found to be significantly (P less than 0.01) better than that of Desi black (15.42) birds. The results further showed depression in production potential of field Desi chickens in comparison to previous production data recorded in the earlier period.

One of the first potential biotechnology products for animals production is BST. Effect of BST on lactating buffaloes was studied 8 buffaloes (Bubalus bubalis) were injected with sustained release formation Boosting-250, after 60 plus minus 5 days of calving. The overall increase in milk production was observed 18 percent and in milk fat 6.1 percent. BST is a protein hormone. Quality of management is the major factor affecting the magnitude of milk response to BST.

A study was conducted to determine the effect of different nutrients i.e. metabolizable energy (ME) and crude protein (CP) content of ration on the egg production and egg weight of rural layers. For the purpose six different experimental rations containing 2700, 2900 kcal/kg ME and 14, 16, 18 percent CP were offered to the birds. The results indicated that egg number increased with proportional adversely affected as the CP of the ration was increased weight of the layers was proportionally increased with ration at constant ME level, while increase in ME level egg weight. increase in ME, while it was at constant ME level. The egg increase in CP content of the did not significantly affect the egg weight.

This study was conducted to examine comparative productive performance of different varieties of Desi chickens identified from group of Desi flock procured from rural field conditions of Mianwali and Bhakkar districts of Punjab province (Pakistan). A total of five varieties of Desi chickens viz., dark brown, medium brown, light brown, black and mixed colour were identified on the basis of their plumage colour and uniformity of body characters. Four hundred and eighty birds (96 of each variety) were selected for further study. The birds of each variety were randomly divided into 3 equal replicates. They were maintained in 15 separate pens on deep litter system under optimal managemental conditions and were fed a balanced layers ration ad-libitum. The birds were provided 16 hours light per day. The experiment was conducted for 8 weeks. The results indicated that varieties differed significantly in egg production, feed conversion efficiency and egg mass, whereas, no difference was observed in feed intake and egg weight between them. Based on the findings of this study, it appeared that different varieties of Desi chickens identified and selected during the course of this study on phenotypic basis differed in their productive potential on the basis of better productive potentials in terms of egg yield, FCR and egg mass, dark brown, and black varieties of Desi chickens could be used to carry out further selective breeding work to study possibility of improving their productive potentials.

Oligodendrocytes and myelin in the corpus callosum of black tremor and normal hamsters aged over 1.5 years were ultrastructurally examined to determine the myelination index (ratio of myelin thickness/diameter of axon), percentage of naked axons, and proportions of oligodendroglial subtypes (light, medium and dark). The mutant hamsters were remarkably hypomyelinated, with a low myelination index and a high proportion of naked axons, and high proportions of the dark subtypes. Serum concentrations of thyroid hormones (T sub(3) and T sub(4)) in 6-week-old mutant hamsters were 2-fold (T sub(3)) to 3-fold (T sub(4)) higher than those of age-matched normal animals. However, in the aged animals (over 1.5 years old) only T sub(4) levels of the mutant hamsters were higher in the mutant than normal hamsters. The black tremor hamsters were hypomyelinated throughout their life and high serum level of thyroid hormones might have played a role in the hypomyelination.