Laying parameters of meat quails breeders submitted to lighting programs at growing phase

ABSTRACT: When applied at growing phase, lighting program aims to obtain quails with body weight and physiological maturity suitable for the beginning of laying. This study evaluated lighting programs at growing phase on performance, sexual maturity and egg quality of meat quail breeders (Coturnixcoturnix) at laying phase. From 7 to 49 days of age, 300 female meat quails were subjected to three lighting programs (natural, intermittent and continuous), with 5 replicates of 20 birds each. At 49 days of age, 240 quails were transferred to a shed, maintaining the same experimental conditions. Meat quails submitted to continuous and intermittent lighting programs had higher weight of reproductive system and lower ages for first egg production and to reach 50% of egg production (P < 0.05). Quails submitted to natural lighting had lower feed intake from 49 to 70 and 71 to 92 days of age and worse feed conversion up to 114 days of age. Continuous and intermittent lighting programs resulted in more precocious quails compared to natural lighting program. Quails submitted to natural lighting at growing phase presented lower egg production during all periods, not differing for birds submitted to continuous and intermittent programs from the second period (71 to 92 days of age). Intermittent and continuous lighting result in better feed conversion of breeding quails up to 114 days and a higher percentage of laying (49 to 136 days), reducing the number of days to produce the first egg and to reach 50% of laying, in relation to natural lighting

INCLUSION OF ANNATTO SEED BY-PRODUCT IN DIETS CONTAINING SORGHUM FOR SLOW-GROWTH BROILERS

Sorghum is used as a source of energy alternative to corn, however, its low pigments content are considered hindrance to the use of this feedstuff for poultry. The inclusion of annatto seed by-product (ASB) may solve this problem. In this context, the objective of this study was to evaluate the effect of ASB inclusion in diets containing sorghum as the main source of energy on performance, carcass traits, meat color, and economic viability in the production of slow-growth broilers. A total of 420 sexed chicks of the Carijó Pesadão line were distributed in a completely randomized design according to a 2 × 7 factorial arrangement, with three replicates of 10 birds per treatment. Studied factors were two sexes (males and females) and seven diets, wherein one had corn as source of energy and the others contained sorghum plus inclusion of 0, 3, 6, 9, 12, and 15% of ASB. Irrespective of the sex, diets did not affect feed intake (g/bird), feed conversion (g/g), yields (%) of carcass, breast and drumstick+thigh, percentage of abdominal fat, or relative weight of the liver. However, the inclusion of ASB influenced the color parameters of the meat making it more pigmented and improved the economic viability parameters. In diets for slow-growth birds containing sorghum as the main source of energy, ASB can be included up to 15%, and meat pigmentation problems can be reduced with total substitution of corn by sorghum with inclusion of ASB from 3%

Ethanolic extract of mango seed used in the feeding of broilers: effects on phenolic compounds, antioxidant activity, and meat quality

The objective of this study was to evaluate the effect of including different levels of ethanolic extract of mango seed (EEMS) in broiler chicken rations on their phenolic compound levels, antioxidant activity, and meat quality. Initially, 756 one-day-old male chicks of the Ross 308 line were distributed in a completely randomized experimental design with seven treatments and six replicates of 18 birds. The treatments consisted of (i) a ration without the addition of antioxidants, (ii) a ration with the addition of 200 ppm of the antioxidant butylated hydroxytoluene (BHT), and (iii) a ration with the addition of 200, 400, 600, 800, or 1000 ppm of EEMS. According to the results, the values of phenolic compounds, the lipid stability of meat (measured by the value of thiobarbituric acid reactive substances), shear force, loss of cooking water, color, and pH of the meat differed significantly between the treatments. For the antioxidant activity of the meat, there was no significant difference between the treatments by the 2,2-diphenyl-1-picrylhydrazyl method; however, by the 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) method, the breast meat of broilers fed diets containing EEMS from 600 ppm and up presented higher antioxidant capacity when compared with the meat of the birds fed the control diet. In the ABTS method, there was no significant difference between the use of synthetic antioxidant BHT and the addition of EEMS at different levels. In conclusion, the addition of EEMS does not affect meat quality parameters of broilers, but when a dose of 600 ppm or more is added, the antioxidant capacity of meat measured by the ABTS method increases.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author