Effect of broiler breeders fed with corn or sorghum diet and canthaxanthin supplementation on production and reproductive performance.

This study was designed to evaluate the effect of corn or sorghum diet and canthaxanthin (CX) supplementation on performance in broiler breeders. A total of 440 females with similar body weight (BW) (3.71 ± 0.14 kg) and 60 roosters were placed in an open-sided house with 20 pens, randomly distributed in a factorial arrangement (2 × 2). There were 4 diets of 2 ingredients; corn (CO) or sorghum (SO) and 2 levels of CX; 6 mg/kg (CX) and 0 mg/kg (NCX) totaling 5 replicate pens of 22 females and 3 males each, from 42 to 65 wk, divided in 2 periods (from wk 42 to 53 and wk 54 to 65). Birds' BW was measured every 28 d and mortality rate was calculated at the end of trial. Egg production (%), egg specific gravity (g/cm3), egg weight (g), yolk weight (%), albumen weight (%), eggshell weight (%) and yolk colorimetric score were measured weekly. Incubation parameters were recorded in 12 incubations to evaluate hatching eggs, hatching (%), hatchability (%), fertility (%), weight of the chicks born and their quality. The BW, mortality, percentage of yolk and albumen weight, fertility and some incubation parameters were not affected (P > 0.05) by diets used. An increase in the egg production, hatching eggs, chicks born and first quality chick by hen at the second period were observed in CX breeder's diets (P = 0.0066; P = 0.0060; P = 0.0368; P = 0.0326). Egg specific gravity and eggshell weight were improved at the first period by SO+CX diet (P = 0.0138; P = 0.0209) and the same effect to egg weight, but at the second period (P = 0.0251). The CX was well absorbed from the diet and effectively transferred to the egg yolk, thereby increasing egg yolk pigmentation in the both periods (P < 0.0001). The CX supplementation in broiler breeder diets improved the productive and reproductive performance (laying% and hatchable eggs) at the second period, also to the both periods improved the egg yolk pigmentation.

Photogrammetry: a non-invasive and objective method for detecting locomotion problems in broiler chickens

Locomotion problems in broiler chickens can cause economic losses of up to 40% of the total revenues due to carcass condemnation and downgrading at processing. Leg disorders, such as femoral lesions, tibial dyschondroplasia, and spondylolisthesis, substantially impact the welfare of chickens as these disorders can prevent birds from reaching the feeders and drinkers, thus reducing feed and water intake. The most important issues related to broiler welfare reported in the last two decades are their growing sensitivity to metabolic and locomotion problems due to the fast growth rates and inactivity. Traditional methods for the determination of gait score include the manual scoring of animal behavior in the broiler house. Recorded video images can also be used for manual scoring of chicken gait score. However, scoring of some animal-based information by human experts and manual methods remain difficult, time consuming and expensive when implemented at farm level. In an effort to objectively detect leg disorders, this study aimed at validating the photogrammetry technique as a non-invasive method for identifying locomotion problems in broilers. Photogrammetry allows determining the geometric properties of broilers from digital photos that are processed and analyzed using a computer software. Results obtained using photogrammetry were tested for their correlation with those obtained by accepted methodologies, including gait score and macroscopic examination of femoral degeneration and tibial dyschondroplasia. The photogrammetry results agreed with the results of the afore mentioned accepted methods.

Photogrammetry: a non-invasive and objective method for detecting locomotion problems in broiler chickens

Locomotion problems in broiler chickens can cause economic losses of up to 40% of the total revenues due to carcass condemnation and downgrading at processing. Leg disorders, such as femoral lesions, tibial dyschondroplasia, and spondylolisthesis, substantially impact the welfare of chickens as these disorders can prevent birds from reaching the feeders and drinkers, thus reducing feed and water intake. The most important issues related to broiler welfare reported in the last two decades are their growing sensitivity to metabolic and locomotion problems due to the fast growth rates and inactivity. Traditional methods for the determination of gait score include the manual scoring of animal behavior in the broiler house. Recorded video images can also be used for manual scoring of chicken gait score. However, scoring of some animal-based information by human experts and manual methods remain difficult, time consuming and expensive when implemented at farm level. In an effort to objectively detect leg disorders, this study aimed at validating the photogrammetry technique as a non-invasive method for identifying locomotion problems in broilers. Photogrammetry allows determining the geometric properties of broilers from digital photos that are processed and analyzed using a computer software. Results obtained using photogrammetry were tested for their correlation with those obtained by accepted methodologies, including gait score and macroscopic examination of femoral degeneration and tibial dyschondroplasia. The photogrammetry results agreed with the results of the afore mentioned accepted methods.(AU)

Live Performance, Carcass Yield, and Welfare of Broilers of Different Genetic Strains Reared at Different Housing Densities

This study evaluated the performance, carcass yield and quality, and physiological stress indicators of broilers of three genetic strains reared at three housing densities for 29 days. A total of 828 day-old male chicks, with average initial weight of 40.0± 2.0g were used. Three genetic strains (Cobb 500, Ross 808, and Ross 508, with 276 birds each) and three housing densities (17, 19, and 21 broilers/m²) were tested. A completely randomized experimental design in a 3 x 3 factorial arrangement, with four replicates of 23 birds each, was applied. The following responses were evaluated: performance parameters (average weekly body weight, average daily gain, feed intake, feed conversion ratio), physiological stress indicators (blood glucose levels, blood cell counts), and carcass yield and quality (dermatosis, bruising, dermatitis, and femoral degeneration scores). Average weekly body weight (BW) and daily weight gain (DWG) were not influenced by rearing density (p0.05), but Cobb 500 broilers were the heaviest during the analyzed period. In the second week, Ross 508 birds showed better feed conversion ratio (FCR) when housed at the density of 17 broilers/m² (p0.001), whereas the best FCR of Ross 808 and Cobb 500 broilers was obtained at 21 broilers/m² (p0.001). Carcass yield was not influenced by the treatments (p0.05). Physiological stress indicators were not affected by the treatments, and remained within normal ranges (p0.05). Dermatosis scores (scratches) increased (p0.05) when housing density increased from 17 to 19 broilers /m².

Live Performance, Carcass Yield, and Welfare of Broilers of Different Genetic Strains Reared at Different Housing Densities

This study evaluated the performance, carcass yield and quality, and physiological stress indicators of broilers of three genetic strains reared at three housing densities for 29 days. A total of 828 day-old male chicks, with average initial weight of 40.0± 2.0g were used. Three genetic strains (Cobb 500, Ross 808, and Ross 508, with 276 birds each) and three housing densities (17, 19, and 21 broilers/m²) were tested. A completely randomized experimental design in a 3 x 3 factorial arrangement, with four replicates of 23 birds each, was applied. The following responses were evaluated: performance parameters (average weekly body weight, average daily gain, feed intake, feed conversion ratio), physiological stress indicators (blood glucose levels, blood cell counts), and carcass yield and quality (dermatosis, bruising, dermatitis, and femoral degeneration scores). Average weekly body weight (BW) and daily weight gain (DWG) were not influenced by rearing density (p0.05), but Cobb 500 broilers were the heaviest during the analyzed period. In the second week, Ross 508 birds showed better feed conversion ratio (FCR) when housed at the density of 17 broilers/m² (p0.001), whereas the best FCR of Ross 808 and Cobb 500 broilers was obtained at 21 broilers/m² (p0.001). Carcass yield was not influenced by the treatments (p0.05). Physiological stress indicators were not affected by the treatments, and remained within normal ranges (p0.05). Dermatosis scores (scratches) increased (p0.05) when housing density increased from 17 to 19 broilers /m².(AU)

Main factors that affect the economic efficiency of broiler breeder production

This study aimed at identifying the factors that affect the economic efficiency of broiler breeder production using the analysis of stochastic profit frontier function. Data were collected in 48 broiler breeder farms contracted by a commercial company located in southwestern Paraná, Brazil. The collected data refer to the last batch of fertile eggs that was delivered to the company, between January, 2008, and July, 2009. The following parameters were evaluated: production of hatching eggs per hen (number of eggs/hen), hatchability (hatch %), feed intake per hatching egg (g feed/ egg), production scale (number of birds/batch), farmer's experience in production activities, and labor type. Factors, such as area of occupied land, electricity costs, and invested capital were also evaluated. Results showed that the cost of electricity, as well as area of occupied land, production scale, and feed intake per hatching egg significantly affect the economic efficiency of the broiler breeder farms in Southwestern Paraná, Brazil.

Main factors that affect the economic efficiency of broiler breeder production

This study aimed at identifying the factors that affect the economic efficiency of broiler breeder production using the analysis of stochastic profit frontier function. Data were collected in 48 broiler breeder farms contracted by a commercial company located in southwestern Paraná, Brazil. The collected data refer to the last batch of fertile eggs that was delivered to the company, between January, 2008, and July, 2009. The following parameters were evaluated: production of hatching eggs per hen (number of eggs/hen), hatchability (hatch %), feed intake per hatching egg (g feed/ egg), production scale (number of birds/batch), farmer's experience in production activities, and labor type. Factors, such as area of occupied land, electricity costs, and invested capital were also evaluated. Results showed that the cost of electricity, as well as area of occupied land, production scale, and feed intake per hatching egg significantly affect the economic efficiency of the broiler breeder farms in Southwestern Paraná, Brazil.(AU)