Universally, domestic chickens are considered very important due to their better adaptability to the local climatic conditions. Among native poultry breeds of Pakistan, Aseel is a recognized native breed used mostly for backyard poultry production and is famous for its appreciable degree of resistance to various diseases as compared with commercial exotic poultry breeds. In many communities, native chickens are considered very important in breaking the vicious poverty cycle. This breed contains genes and alleles appropriate to their adaptation to the specific environment. On the basis of its characteristic of producing good quality meat, Aseel chicken can be used and further improved as a meat type bird. However, the main limitation in its propagation is its slower growth rate, poorer egg production, smaller egg size, lower fertility and hatchability.Selenium (Se) is an essential micro-mineral for poultry which exists in organic and inorganic forms. Organic Se is reported to be more bio-available which improves the growth performance, productive and reproductive potential of poultry resulting in better egg and meat production as well as the quality. Despite having considerable capabilities, inadequate research work has been so far conducted on Aseel that may be the main bottleneck towards increasing its overall production. In this study, there was a focus on the improvement of growth, productive and reproductive potential of Aseel; also for the development of functional poultry products (eggs and meat, enriched with Se). The present study was planned with the main objectives to investigate the influence of organic (Se-enriched yeast: SY) and inorganic (sodium selenite: SS) Se dietary supplements on growth performance, nutrient utilization, blood biochemical profile, slaughter characteristics, tissue Se concentration, rearing expenditures andmortality as well as the production traits including egg production, egg quality/geometry, hatching traits and egg Se concentration in four recognized varieties namely Lakha, Mushki, Peshaweri and Mianwaliof indigenous Aseel chicken. The study comprised two main experiments conducted at the Indigenous Chicken Genetic Resource Centre (ICGRC), Department of Poultry Production, University of Veterinary and Animal Sciences (UVAS), Ravi campus, Block-C, Pattoki with the objectives to explore theimpact of dietary Se addition, influence of varieties and their interaction on overall performance of Aseel chickens. For this purpose, in the first experiment, 240 three-week-aged birds (120 males and 120 females) were distributed in a randomized complete block design into four groups, 60/variety (30 males + 30 females). These birds of either sex were further subdivided into three treatment groups A, B and C according to the nature of diet (SY added, SS added and without Se added) with 10 birds/treatment and each treatment was replicated 10 times with one bird in each replicate. Data thus collected were subjected to analysis of variance techniques in a randomized complete block design and means were compared using Duncan’s Multiple Range test. The studies regarding overall response to Se supplementation for growth performance depicted substantial influence. Dietary addition with SY increased the nutrient retention, feed conversion, body weight and decreased the mortality and rearing expenditures, especially in the males of Lakha variety. All body measurementswere improved in the birds received SY supplemented diet, the SY-fed males of Lakha exhibited better response compared to rest of the treatments.SY addition significantly increased the values of glucose, triglyceride, globulin, glutathione peroxidase (GPX) in blood serum, while significantly decreased levels of urea, creatinine, uric acid, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol, and thyroxine (T4) in the serum were observed in SY-fed birds, especially in the birds of Lakha and Peshaweri varieties. However, total protein and albumin values in the serumwere foundunaffected by Se supplementation. The significant variations in the slaughtering traits were observed; SY inclusion presented improved live final body weight, dressing weight, dressing percent, eviscerated weight, eviscerated percent and giblet weight. Selenium uptake by the chest and thigh muscles was also enhanced in the male birds of Lakha and Mushki varieties exposed to SY added diet. The rearing cost of the birds in SY-fedgroup was noticed lower than the cost recorded for those got SS supplemented or control diet. The males of Lakha in this regard presented the least rearing cost on receiving SY supplemented diet.
The second experiment was also conducted with the objectives to compare the influence of organic and inorganic Se inclusion, varieties and their interaction on productive performance, egg geometry/quality traits, reproductive performance and the egg Se contents in Aseel. For this purpose, 96 twenty-one-weeks old birds (84 females and 12 Males) from Lakha, Mushki, Peshaweri and Mianwali varieties of Aseel were selected and distributed under randomized complete block design into three groups, 24/variety (21 females + 3 males); further subdivided into three treatment groups, 7 females and 1 male in each treatment according to Se treatments (SY, SS and control) and each treatment was replicated 7 times with one bird in each replicate. Each bird was regarded as an experimental unit. The data thus collected were subjected to analysis of variance in a randomized complete block design and means were compared using Duncan’s Multiple Range test. The results showed that the females of Mianwali variety fed with SY supplemented ration exhibited higher feed intake, enhanced body weight and gained sexual maturity earlier; furthermore, Mianwali variety exhibited better egg production, showed higher egg weight and egg mass. FCR/dozen eggs, FCR/kg egg mass were as observed to be higher in the females of Peshaweri variety. Egg Se concentration was higher in the SY supplemented group as compared with SS or control groups.Dietary Se supplementation significantly influenced the shape index, yolk index, Haugh Units and eggshell thickness. However, non-significant variations were observed in Haugh Units among the females of all varieties. Interaction results presented the significant differences in egg breadth, egg length, egg volume, egg weight, egg shape index, egg shell thickness, yolk index and Haugh Units in the females of all varieties; with significantly higher values in the females of Mianwali variety exposed to SY added ration.The reproductive performance pertaining to hatching traits depicted that the Se supplements, varieties and their interaction influenced the hatching traitssignificantly. The SY-fed females of Peshaweri presented the decreased dead germ percent, dead in shell percent and clear egg percent compared with the females got SS supplemented ration or unsupplemented control ration. Improved hatchability percent and the hatch of fertile percent were noticed in the females of SY supplemented group than those of SS or control groups and the greatest increase was recorded in the females of Peshaweri variety. Similarly, enhanced body weights by the newly hatched chicks of Peshaweri and Mianwali varieties were observed fed with SY supplemented ration and also in the interaction, significant results were recorded.
9.1 CONCLUSIONS
Based upon the findings of the present study, it can be concluded that all four varieties of indigenous Aseel responded positively to the dietary addition with SY supplements of Se regarding growth performance of Aseel, especially in the male birds of Lakha variety. SY supplementation also showed the better results regarding productive and reproductive performance, especiallyin the females of Mianwali and Peshaweri varieties with more promising results. Moreover, SY addition displayed the substantial results in shape of production of functional foods such as Se-enriched eggs and meat.


9.2 SUGGESTIONS AND RECOMMENDATIONS
In future, indigenous Aseel chicken raising programs should be given due emphasis while proceeding for poultry farming by using native breeds of poultry.
9.2.1 Recommendations for the farmers
Keeping in mind the results of this study, here are some recommendations for the poultry farmers.
1. Due to the large body size of Aseel and a good ability to show resistance against a variety of infectious diseases, many poultry farmers want to rear and use Aseel as a parent flock for further breeding but are hesitant to go for that because of its slow growth. Slow growth is due to its low feed nutrient utilization and consequently slow gain in body weight. Lower production performance is mainly due to its late sexual maturity, long pauses and short clutch size.In the current situation,the strategic inclusion of Se in the diets of Aseel, being the effective technology, can help the farmers overcome the problems of slow growth and low productive performance in Aseel by synchronizing and consequently bringing the Aseel birds into better growth and production. It can help the farmers to get the production of the Aseel birds, according to their need and situations.
2. In the current study, SY has been substantiated to improve the reproductive performance of Aseel, hence can be used further to elucidate the very old concern of lower fertility and hatchability in Aseel parent flock consequently improving progeny size.
3. Keeping in view the above, the Aseel can be used as a feasible option for the poultry business by enhancing its sluggish growth rate and lower production potential through Se supplementation as well as to lower fertility and hatchability through the supplementation of organic Se supplement (SY) in the diet. Ultimately, it will be remained supportive towards the revival of open- sided poultry farms that have become closed after the trend to establish the environmentally controlled sheds and are lying vacant from a long time.
9.2.2 Suggestions for the researchers
1. In the current study, the fixed levels ofSe supplements were used for supplementation, whereas future researchers can work on different levels of it.
2. Further trials may be planned to check the subsequent effects of different sources of Se supplements on the biochemical profile of meat and eggs; also the immune response in the chicks from hens reared on Se supplemented diets.
3. The evaluation of semen quality in Aseel males and the impact of artificial insemination in the hens by the semen received from Se treated males of Aseel can also be studied.