The diseases in poultry cause huge losses in the form of mortality in acute infections or as substandard performance due to chronic illness. Biosecurity and vaccination are considered as two important primary strategies for disease prevention in poultry. On the other hand, breeding for disease resistance is an alternate strategy to combat the damages of diseases. Although, attempts were initiated to develop disease resistant poultry by breeding almost a century before, this branch of science renewed the interest among scientists because of catastrophic emerging and reemerging diseases like Avian influenza. It has proven over a period of time that poultry  exhibits genetic resistance to viral diseases like avian leukosis complex, Marek’s disease, avian influenza and Newcastle disease, bacterial disease like salmonellosis and may parasitic infestations. The key genes responsible for resistance to specific diseases have also been demonstrated. The breeding attempts for developing disease resistant poultry has yielded positive results with varying degree of success. The advent of sophisticated molecular methods like genomic selection using highdensity SNP chips, RNA-seq technique and identification of key marker genes and transgenesis could complement the conventional breeding methods to a larger extent in developing disease resistant poultry.

The identification and development of new and effective alternatives to antibiotics that do not hinder productivity assumes paramount importance in the context of antimicrobial resistance and food safety. In recent years, phytobiotics have been used as natural growth promoters in ruminants, poultry and swine, to improve growth and health. A wide variety of herbs, spices and essential oils have been used individually or as blends in poultry for their potential application as alternative growth promoters. In nursery and growing pigs supplemented with phytobiotics, intestinal pathogens were inhibited and beneficial microbial population that contributes to improving digestion and absorption of nutrients were increased resulting in increased weight gain and decrease in diarrheal syndrome. The inclusion of essential oils in the diet of finishing pigs, improved the productive yield and carcass characteristics. It also reduced the incidence of therapeutic treatment and mortality. Natural plant products have the potential to improve rumen fermentation, reduce loss of feed energy, improve animal health and productivity, increase animal lifetime performance, and reduce greenhouse gases production in ruminants. Phytobiotics with wide range of activities, is projected as a feed additive for higher market growth compared to other alternatives to antibiotics in the feed industry.

Different selective culture media were evaluated for isolation of Aeromonas spp. from 120 poultry meat samples. The recovery ofAeromonas isolates was highest fromAmpicillin DextrinAgar (89.39%), followed by Aeromonas Starch DNAse agar (68.18 %) andAeromonas isolation media (18.18 %).

In the study, 348 bacterial isolates comprising of Escherichia coli (100), Klebsiella aerogens (45), Proteus mirablis (35), Peudomonas aerogens (20), Staphylococcus sp. (78), Streptococcus sp. (13), Bacillus sp. (57) were isolated from egg shell and egg contents of 150 egg samples collected from local market in Patna (Bihar). The isolates were subjected to antibiogram. This study demonstrated that egg from organized farm microbial contamination than unorganized poultry farm reflecting the effect of environment, storage and transportation on microbial quality of eggs.

A biological trial was conducted to investigate the effect of bacteriophage on carcass characteristics of commercial broilers with or without bacterial challenge. Totally 180 day old Vencobb broiler chicks were randomly allotted into five dietary treatments designated as T1 to T5 with each treatment replicated thrice. T1 and T2 served as negative and positive control respectively, while birds in T3, T4 and T5 were exposed to E. coli on different days during 35 days course. Dietary treatments included T1 - basal diet, T2 - basal diet with bacteriophage in feed (50 mg/bird/ day up to 7th day and 25 mg/bird/day up to 35th day), T3 without bacteriophage, T4-bacteriophage in feed (50 mg/bird/day up to 35th day) and T5 - bacteriophage in feed (50 mg/bird/day up to 7th day and 25mg/bird/ day up to 35th day). E. coli was introduced orally in groups T3 and T4 on day 10, while T5 on day 26 (106 CFU/ bird). The bacteriophage supplementation to E. coli challenged birds had significantly increased the weights of eviscerated carcass, giblets, ready-to-cook meat; the cut-up parts like breast, back and drumstick compared to non-supplemented group. Results shed light on the potential benefits of bacteriophage as a natural alternate approach to antibiotic growth promotors in broiler production.