Supplementation of sulfur and folic acid improves performance of broiler chicken fed suboptimal concentrations of dietary methionine.

BACKGROUND: Supplementation of sulfur (S) and folic acid (FA) are known to spare the dietary requirement of methionine (Met) in chicken. An experiment was conducted to determine the effects of feeding graded concentrations of FA (0, 2, 4, 6, 8 mg kg-1 ) and two concentrations of S (0 and 2 g kg-1 ) in 5 × 2 factorial design. Diet without FA and S was considered as negative control (NC). Another diet with the recommended concentration of Met was considered as the positive control (PC). Each diet was offered ad libitum from day 1 to 42 to 10 pens of 20 male chicks each. RESULTS: Broilers fed the NC diet had lower body weight gain (BWG), high feed conversion ratio, lower ready-to-cook yield, higher lipid peroxidation and reduced concentrations of protein and albumin in serum. BWG improved with FA at day 21 and showed a trend of improvement at day 42. Similarly, BWG improved with S supplementation at day 42. The FA and S interaction indicated a significant reduction in lipid peroxidation with S supplementation at the majority of FA levels. Serum protein fractions increased with increased dietary FA content and increased further with S supplementation. CONCLUSION: Based on the results, it is concluded that the combination of FA (4 mg kg-1 ) and S (2 g kg-1 ) improved BWG. Similarly, the feed efficiency with 6 mg FA alone or with S was similar to the PC group. The improvement was probably due to the increase in protein accretion and reduction in lipid peroxidation with FA and S supplementation. © 2022 Society of Chemical Industry.

Effect of feeding different levels of energy and protein on performance of Aseel breed of chicken during juvenile phase.

A study was conducted to evaluate the effect of feeding different metabolizable energy (ME) and crude protein (CP) levels on performance of Aseel chicken during 0 to 8 weeks of age (Juvenile phase). At 1 day old, 432 chicks were randomly distributed into nine groups. Each group had 48 chicks distributed into eight replicates with six birds in each. Maize-soybean meal-based diets with three ME levels (2,400, 2,600 and 2,800 kcal/kg) and three CP levels (16%, 18% and 20%) were fed to birds in a 3 × 3 factorial design. Different ME levels had significant effect on body weight gain (BWG), feed intake and feed conversion ratio (FCR). Birds fed diet with 2,400 kcal/kg ME had significantly lower BWG (P < 0.004), lower shank length (P < 0.0007), higher feed intake (P < 0.0001) and poor FCR (P < 0.0001) than those fed diet with either 2,600 or 2,800 kcal/kg ME. Energy efficiency ratio was not influenced by ME, CP or their interaction. However, protein efficiency ratio was significantly higher at higher ME levels and lower at higher CP levels. There was significant effect of ME, CP and their interaction on serum protein and cholesterol levels. However, they made no significant effect on antibody titre against New Castle disease vaccine. The study concluded that provision of 2,600 kcal/kg ME and 16% CP would be ideal for optimum growth of Aseel birds during juvenile phase. However, to obtain better FCR, feeding Aseel birds with diet having 2,800 kcal/kg ME and 16% CP would be ideal.

Evaluation of two Indian native chicken breeds for reproduction traits and heritability of juvenile growth traits.

The present study was conducted to evaluate two Indian native chicken breeds, namely, Aseel and Kadaknath for fertility, hatchability, genetic parameters of juvenile growth traits, and semen quality traits at the onset of sexual maturity. The fertility was similar in Aseel (86.96%) and Kadaknath (85.15%); however, a relatively higher hatchability was observed in Kadaknath (77.94%) than Aseel (70.74%). Heritability estimates of body weights at 4 weeks of age were almost similar in Aseel (0.37) and Kadaknath (0.39), while the estimate of body weight at 6 weeks of age was higher in Aseel (0.42) than Kadaknath (0.31). The heritability estimate of shank length at 6 weeks of age was lower in Aseel (0.16) compared to Kadaknath (0.35). The age at first egg in the flock was comparable in Aseel (148 days) and Kadaknath (150 days). Aseel breed with significantly (P ≤ 0.001) higher body weight, absolute and relative testes weights had significantly higher semen volume (P ≤ 0.05) and sperm motility (P ≤ 0.01) but had lower seminal plasma cholesterol level (P ≤ 0.05) as compared to Kadaknath. It can be concluded that there is a scope for genetic improvement of these two native breeds for juvenile growth traits since heritability estimates of these traits were relatively high.

Genetic analysis of juvenile growth and carcass traits in a full diallel mating in selected colored broiler lines.

The juvenile growth and carcass traits were evaluated in a 4 × 4 full diallel crossing involving four colored broiler chicken lines viz., Naked neck (NN), Dwarf, Punjab Broiler-1 (PB-1), and Punjab Broiler-2 to study the performance and crossbreeding parameters. The data on 2,280 chicks were analyzed using least squares techniques to assess the effect of genetic group, and the significant traits were further analyzed for crossbreeding parameters. Genetic group had significant influence on the body weights and carcass traits. The cross of PB-1 × NN recorded significantly (p ≤ 0.05) higher body weight at 6 weeks of age. The data revealed that general combining ability (GCA), specific combining ability (SCA), maternal ability (MA), sex-linked effect (SE), and purebred effects significantly influenced the growth and carcass traits in the broiler crosses. The crossbred PB-1 × NN showed positive heterosis for growth as well as carcass traits. The results suggest that GCA, SCA, SE, and MA are important in the inheritance of the body weights and carcass traits indicating the presence of both additive and nonadditive genetic variation along with reciprocal effects. Therefore, pure line selection along with development of specialized sire and dam lines followed by crossing will improve the growth performance and benefit the poultry farmers. It is concluded that PB-1 as a male line and NN as a female line performed significantly higher, therefore, may be used for improving the performance of colored broilers.