Genotypic characterization of ten microsatellite loci in two Brazilian free range (Caipira) chicken lines

This study aimed to investigate the genetic variability of two Brazilian free range (Caipira) chickens lines using microsatellites analysis of ten loci. It was collected a total of 99 blood samples, which 49 were from Paraiso Pedres (PP) and 50 were from Rubro Negra (RN) lines. The amplification of the DNA fragments was performed by polymerase chain reaction (PCR) and the genotyping was conduct using ABI 3130 sequencer. The allele number variation was among 3 (LEI0254) to 32 (LEI0212) in the PP line, and 4 (LEI0254) to 31 (LEI0212) in the RN line. The allelic average per locus was 13.3 and 13.1 in the PP and RN lines, respectively. The average observed and the expected heterozygosity were 0.650 and 0.820 in the PP line, and 0.671 and 0.804 in the RN line. All of the analyzed loci were informative (PIC>0.5). These results indicate that these free-range animals have a high genetic variability, at least for the majority of the analyzed loci, and this genetic variation is higher than the commercial chickens and similar for the no-commercial birds.

Use of prebiotics and probiotics of bacterial and yeast origin for free-range broiler chickens

This study aimed to evaluate the effects of probiotics and prebiotics of bacterial and yeast origin on the performance, development of the digestive system, carcass yield and meat quality of free-range broiler chickens. Five hundred and sixty male chicks of the strain ISA S757-N were reared from one to 84 days old. The birds were distributed in four treatments according to a completely randomized block design: T1 = Control, T2 = Probiotics and Prebiotics of bacterial origin, T3 = Probiotics and prebiotics of yeast origin, T4 = Probiotics and prebiotics of bacterial origin + probiotics and prebiotics of yeast origin. There were four repetitions with 35 birds per repetition, and the birds had access to a pasture area after 35 days of age. Characteristics evaluated were performance, development of the digestive system, carcass and parts yield, abdominal fat, breast meat physical measurements (length, width and height) and meat quality parameters (pH from breast and leg meat, cooking loss and shearing force from breast meat). Lower mortality (p<0.05) and higher weight gain from 64 to 77 and 64 to 84 days of age were seen in birds supplemented with probiotics and prebiotics of bacterial origin compared to the non-supplemented birds (control). There were significant differences (p<0.05) among treatments for carcass yield. Birds supplemented with both probiotics and prebiotics of microbial and yeast origin (T4) showed higher carcass yield than control birds. Supplementation with probiotics and prebiotics of bacterial origin (T2) or the supplementation of these together with those of yeast origin (T4) reduced mortality and increased the carcass yield in free-range broiler chickens.

Efficiency of prebiotics and probiotics on the performance, yield, meat quality and presence of Salmonella spp in carcasses of free-range broiler chickens

Two trials were carried out in the present study. Trial I evaluated the performance, carcass yield and breast meat quality, whereas Trial II evaluated the efficacy of utilizing prebiotics + probiotics on the control of Salmonella spp incidence in the carcasses of free-range broilers. In Trial I, 688 one-day-old male chicks of the Naked Neck Label Rouge strain were used, distributed in a randomized block design arranged according to a 2 x 2 factorial: control diet or diet supplemented with probiotics and prebiotics; and two rearing systems (confined or with access to paddocks - 3m²/bird), using four replicates with 35 birds each. The birds were reared until 84 days of age following the recommendations of management and nutrition for free-range strains, and had access to paddocks after 35 days of age. Water and food were given inside the experimental poultry house. Birds fed probiotics and prebiotics in the diet and the confined birds showed better performance, carcass yield and meat quality compared to the birds of the other treatments. In Trial II, 128 one-day-old male chicks of the free-range Naked Neck Label Rouge strain were used. The birds were distributed into four treatments: NCC (non-challenged control), NCS (non-challenged supplemented), CC (challenged control) and CS (challenged supplemented). There were no significant effects of adding probiotics and prebiotics in the diet in regard to Salmonella enteritidis recovery from the carcasses.

Efeito do sistema de criação sobre o desempenho e rendimento de carcaça de frangos de corte tipo colonial

Foram utilizados 1600 pintos de corte de um dia de idade, distribuídos em delineamento, em blocos ao acaso, com esquema fatorial 4×2 (quatro linhagens, sendo uma delas comercial (Ross-308) e as demais específicas para a produção colonial (Caipirinha, Pescoço Pelado e Paraíso Pedrês) e dois sistemas de criação (confinado e com acesso a piquete), com quatro repetições de 50 aves cada. A ração não continha promotores químicos de crescimento e produtos de origem animal. Avaliaram-se o ganho de peso, o consumo de ração, a conversão alimentar, a mortalidade e os rendimentos de carcaça e das partes (peito, pernas, asas e dorso) aos 56, 63, 70, 77 e 84 dias de idade. O comprimento e a porcentagem (em relação ao peso vivo) dos intestinos e o peso e a porcentagem (em relação ao peso vivo) do fígado, moela e pâncreas foram avaliados aos 84 dias de idade. Houve efeito (P<0,05) da linhagem para as características de desempenho e da linhagem e do sexo para rendimentos da carcaça e das partes, assim como para as características do sistema digestório (P<0,05). O sistema de criação não influenciou as características avaliadas.

Efeito do sistema de criação sobre o desempenho e qualidade da carne de frangos de corte tipo colonial e industrial

Pós-graduação em Zootecnia - FMVZ

Free range chicken farms - odour emissions and nutrient management

Quantification of air emissions, in particular, from free range farms for comparison with conventional farming may demonstrate that free range farming has lower emissions. This finding may support conventional farms that are under pressure due to air quality impacts to more readily convert to free range. Industry will benefit by maintaining/increasing production and the community will benefit from fewer impacts.

Relationships between flavour, lipid composition and antioxidants in organic, free-range and conventional chicken breasts from modelling

Consumers expect organic, free-range and corn-fed chicken to be nutritionally wholesome and have premium flavour characters. Interrelationships between flavour, fatty acids and antioxidants of retailed breasts were explored using simple correlations and chemometrics. Saturated fatty acid C16:0, and n-6 polyunsaturated C20:4 and C22:4 contents were correlated with lipid oxidation products (thiobarbituric acid reactive substances) and in partial least-squares regression (PLS1) with 32 high-resonance gas chromatography (flame ionization) flavour components (r2>0.90), and also linked (r2>0.80) to antioxidants (-tocopherol, glutathione and catalase). A further 10 high-resonance gas chromatography nitrogen phosphorus detector flavour components were correlated (r 2>0.85) with C18:3(n-3) content. Chicken character was correlated with C18:3(n-3), and C18:3(n-6) inversely with oily, off-flavour and lipid oxidation. Sweet, fruity and oily aromas were linked in PLS1 with 13 specific fatty acids (r2>0.6), and bland taste with total summed (six) fatty acid fractions (r2>0.81). Specific antioxidants were correlated with sweet, fruity and chicken aromas, and -tocopherol inversely with lipid oxidation. PLS2 confirmed relationships between fatty acid composition, antioxidants and the subsets of 32 and 10 flavour components. Clear relationships were thus observed between lipid and antioxidant compositions and flavour in chicken breast meat.

Free-range village chickens on the Accra plains, Ghana: Their contribution to households

A cross-sectional survey investigating the contribution of free-range village chickens to household economies was carried out in four administrative districts within 60km of Accra. Answers were provided by 101 men and 99 women. Nearly all respondents claimed to keep chickens for meat, with a far smaller percentage claiming to keep them for egg production. Over 80% of respondents kept chickens to supplement their incomes. The proportion of the flock eaten varied between administrative areas (p=0.009 and p=0.027), although this was possibly a consequence of differences in consumption patterns between occupation of the respondent, land area cultivated and flock size. The proportion of chickens sold varied as a result of differences in flock size (p=0.013), the proportion sold increasing with number of birds in the flock. Respondents generally agreed that chickens could be sold without difficulty. A majority of chicken sales were from the farm gate, directly to consumers or traders. Sales were on demand or when the owner needed money. Money from the sale was kept by the owner of the chicken and the money was spent on personal needs. The proportion of the flock sold varied between administrative areas (p=0.025) and occupation of the respondent (p=0.040). Respondents describing animal production as their main occupation tended to have greater reliance on chicken sales for their income. Consideration is given to estimating the offtake from the flock and the financial contribution to the household.

Phytogenic additives and organic acids in broiler chicken diets

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Seroprevalence and isolation of Toxoplasma gondii from free-range chickens from Espirito Santo state, southeastern Brazil

Prevalence of Toxoplasma gondii infection in 510 free-range (FR) chickens (380 from 33 small farms, and 130 from a slaughter house for FR chickens) from Espirito Santo state, southeastern Brazil, was investigated. Antibodies to T. gondii were sought using commercial indirect haemagglutination (IHAT, Imuno-HAI Toxo (R), Wama Diagnostica, Sao Paulo, Brazil, cut-off 1:16) and the modified agglutination test (MAT, cut-off 1:25) tests. Attempts were made to isolate viable T. gondii from seropositive chickens by bioassay in mice. Pooled samples of brain, heart and quadriceps muscle of one thigh (total 40 g) from 64 chickens with IHAT titers of >= 1:16 were minced, digested in pepsin and bioassayed in mice. Antibodies to T. gondii were found in 40.4% (206/510) FR chickens by IHAT (titer >= 1:16) and 38.8% (198/510) by MAT (titer >= 1:25); concordance between IHAT and MAT was 81.6% (kappa index = 0.614). Viable T. gondii was isolated (designated TgCkBr234-281) from 48 of 64(75%) seropositive (IHAT titers >= 1:32) FR chickens. Most isolates of T. gondii were virulent for mice; 100% of mice inoculated with 44 of 48 isolates died of toxoplasmosis within 30 days post inoculation (p.i). An epidemiological investigation revealed that people living in rural areas have little knowledge about the parasite and about the risk of acquiring it from raw meat. Results indicated that the locally available IHAT was useful for screening of chicken sera for T. gondii antibodies. (C) 2012 Elsevier B.V. All rights reserved.

Obstacle-free range determination for rail track maintenance vehicles

Maintenance trains travel in convoy. In Australia, only the first train of the convoy pays attention to the track sig- nalization (the other convoy vehicles simply follow the preceding vehicle). Because of human errors, collisions can happen between the maintenance vehicles. Although an anti-collision system based on a laser distance meter is already in operation, the existing system has a limited range due to the curvature of the tracks. In this paper, we introduce an anti-collision system based on vision. The two main ideas are, (1) to warp the camera image into an image where the rails are parallel through a projective transform, and (2) to track the two rail curves simultaneously by evaluating small parallel segments. The performance of the system is demonstrated on an image dataset.

Free Range Hens Use the Range More When the Outdoor Environment Is Enriched.

To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05) higher % of birds in the range (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly more using the shelterbelts in the afternoon than in the morning. Approximately 17 times more birds used the forage areas compared to the control area in the corresponding range. There were 8 times more birds using a hay bale enriched area compared to the area with no hay bales. The use of forage sources (including hay bales) were the most successful method on-farm to attract birds into the range followed by shelterbelts and artificial shade. Free range egg farmers are encouraged to provide pasture, shaded areas and shelterbelts to attract birds into the free range.