Background: Recent developments in molecular genetics lead to addressing certain poultry diseases via breeding for disease resistance. The present study was carried to identify and compare the genetic polymorphism in Chicken Mx1 and TVB genes among the indigenous and Giriraja chicken using PCR-RFLP technique. 
 
Methods: Blood samples were collected from 50 indigenous and 50 Giriraja birds and DNA isolation was done by Phenol: Chloroform: Isoamyl alcohol method. PCR amplification of Chicken Mx1 (exon 14) and Chicken TVB (exon 3) genes was carried out followed by RFLP analysis. 
 
Result: PCR product sizes of 301 bp and 303 bp of Mx1 and TVB genes, respectively were successfully amplified. RFLP analysis of Mx1 gene with Hyp8I restriction enzyme revealed three genotypes AA, AB and BB. In indigenous birds genotypic frequencies of AA, AB and BB were 0.314, 0.493 and 0.194, respectively and gene frequencies were 0.56 and 0.44 for alleles A and B, respectively. In Giriraja birds, genotypic frequencies for AA, AB and BB were 0.27, 0.499 and 0.23, respectively and gene frequencies were 0.52 and 0.48 for alleles A and B, respectively. RFLP analysis of TVB gene with NlaIII restriction enzyme revealed two genotypes viz., AA and AB. In indigenous birds genotypic frequencies of AA and AB were 0.81 and 0.18, respectively and gene frequencies were 0.9 and 0.1 for alleles A and B, respectively. In Giriraja birds genotypic frequencies for AA and AB were 0.774 and 0.211, respectively and gene frequencies were 0.88 and 0.12 for alleles A and B, respectively.

Genetic Polymorphisms of Chicken Antiviral Mx1 and TVB Genes in Indigenous and Giriraja Chicken

<div>Background: Copper (Cu) is an essential trace mineral for growth, production and health of poultry. Due to its poor absorption from inorganic source which is common supplemental form, large amount of Cu is excreted in the excreta. This experiment was conducted to assess the bioavailability of Cu from organic and nano sources at lower level of supplementation to reduce the excretion level without compromising the growth performance of chicken. 
 
Methods: A total of 420-day-old Giriraja chicks were randomly assigned to 7 treatment groups having 4 replicates each (15 chicks per replicate). The basal diets of both chick (0-6 weeks) and grower phases (7-10 weeks) were supplemented with 20 and 30 ppm of Cu from inorganic source as control (T1), the groups T2, T3 and T4 supplemented with 100, 75 and 50% of control from organic Cu, T5, T6 and T7 treatment diets supplemented with 75, 50 and 25% of control from Cu nanoparticles, respectively. 
 
Result: The grower phase and cumulative body weight gain was significantly (p&lt;0.05) higher in T2 compared to T1, T6 and T7 groups, while the feed intake in chick phase was lower in T2, T5 and T7 groups as compared to T1, T3, T4 and T6. The chick phase feed conversion ratio was significantly (p&lt;0.05) better in T2 and T5 groups compared to T1, T3, T4, T6 and T7, whereas the cumulative FCR was better in T2 and T5 compared to T6 and T7 groups, while it was not affected during grower phase. The dry matter and crude protein metabolizability were significantly (p&lt;0.05) higher in T2 and T5, the organic matter and ether extract metabolizability was higher only in T5. The crude fiber and nitrogen free extract was not affected by the treatment diets. Nitrogen excretion was significantly (p&lt;0.05) lower and its retention was higher in T2 and T5 treatment groups but was comparable with control. The Cu excretion through excreta was significantly (p&lt;0.05) higher and its retention was lower in control as compared to all dietary treatments. Hence, it was concluded that the Cu supplementation from organic or nanoparticles form can be reduced by 50 and 75% of standard, respectively without compromising the growth performance of birds and nutrient digestibility of diets.</div>

Genetic Polymorphisms of Chicken Antiviral Mx1 and TVB Genes in Indigenous and Giriraja Chicken

Effect of Reduced Dietary Copper Levels Sourced from Organic and Nanoparticles Forms on Performance and Nutrient Utilization in Giriraja Birds