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1. An experiment was carried out to validate techniques as predictive diagnostic tools for breast myopathies and to study the allometric growth of distinct parts of the body and meat quality of broilers.2. Infrared thermography was performed at 35 d of age. The surface temperatures of breasts of 300 birds were recorded, followed by ultrasound imaging.3. The birds were slaughtered and the cuts were made to weigh the body parts. Then, the breasts were evaluated as for the presence and severity of myopathies, from which nine treatments were established represented by the associated degrees of the myopathies white striping and wooden breast and breasts classified as normal.4. There was no difference in surface temperatures and echogenicity values between normal breasts and breasts affected by myopathies. At 35 d of age few fillets classified as normal were found.5. The breast showed late growth in relation to the body, regardless of characteristic lesions of myopathies. The most severe score of wooden breast affected meat quality variables.

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The main objective of this research was to conduct an exploratory study of the lactation curve in order to characterize the productive potential of Pantaneiro ewes and lambs. Fifty ewes were bred using four rams in two different mating seasons. The ewes were kept with their lambs on pasture of Brachiaria brizantha. Ewe body score, ewe weight, and lamb weight were evaluated. Milk sampling was performed every week. In the morning for milk collections, the ewes were treated with 1 UI of oxytocin (intramuscular) for complete milking. Lambs were separated from the ewes for 4 h and milk collections were performed. The total milk production over 24 h was estimated by multiplying the production of this period (4 h) by 6. The data were analyzed using the MIXED procedure (P < 0.05) in SAS. Milk production data were fitted to the curve using the incomplete gamma function of Wood, and lamb growth data were fitted using the Gompertiz equation. The average milk production of the ewes was 1.03 kg/day-1. Younger ewes had the lowest milk production (18 = 798 ± 330, 24 = 1001 ± 440, 36 = 1100 ± 490, and 48 = 1106 ± 490 g/day-1). Ewe body score at lambing affected initial milk production (1.0 = 816 ± 660, 1.5 = 1089 ± 105, and 2.0 = 1424 ± 1600 g/day-1). Lambs were weaned with an average weight of 20.3 kg. Daily weight gain from birth to weaning was 181 g. Locally adapted Pantaneiro ewes showed a linear decreasing lactation curve, with reduced production from the second week of lactation. Overall, evaluation of the dairy production and lamb performance revealed great variation, denoting potential for selection.

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The aim of this study was to evaluate a genome wide association study (GWAS) approach to identify single nucleotide polymorphisms (SNPs) associated with fertility traits (early puberty) in Nellore cattle (Bos indicus). Fifty-five Nellore cows were selected from a herd monitored for early puberty onset (positive pregnancy at 18 months of age). Extremes of this phenotype were selected; 30 and 25 individuals were pregnant and non-pregnant, respectively, at that age. DNA samples were genotyped using a high-density SNP chip (>777.000 SNP). GWAS using a case-control strategy highlighted a number of significant markers based on their proximity with the Bonferroni correction line. Results indicated that chromosomes 5, 6, 9, 10, and 22 were associated with the traits of interest. The most significant SNPs on these chromosomes were rs133039577, rs110013280, rs134702839, rs109551605, and rs41639155. Candidate genes, as well as quantitative trait loci (QTL) previously reported in the Ensembl and Cattle QTLdb databases, were further investigated. Analysis of the regions close to the SNP on chromosomes 9 and 10 revealed that four QTL had been previously classified under the reproduction category. In conclusion, we have identified SNPs in close proximity to genes associated with reproductive traits. Moreover, U6 spliceosomal RNA was present on three different chromosomes, which is possibly associated with age at first calving, suggesting that it might be a strong candidate for future studies.

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The objective of this study was to evaluate the tissue composition, quality traits and fatty acid profile of longissimus muscle of lambs fed increasing levels of crude glycerin. Twenty-four intact male lambs were allocated in a completely randomized design with four treatments and six replicates. The treatments consisted of the replacement of corn with 0, 2.5, 5.0 and 7.5% crude glycerin (dry matter basis) in the diet. The animals were slaughtered when they reached a body condition score of 2.5 to 3.0. After cooling the carcasses, the meat was removed for the determination of tissue composition and longissimus muscle for the evaluation of quality characteristics. The different crude glycerin levels did not affect tissue weight or yield, or the qualitative characteristics of longissimus muscle. An increasing linear effect was observed for ether extract. There was a quadratic effect on C17:0 fatty acids, and C18:1 n-9c and C18:3 n-3 fatty acids decreased linearly. A quadratic effect was observed for total unsaturated fatty acids and a linear decreasing effect for n-3 fatty acids. The unsaturated:saturated fatty acid ratio decreased linearly and there was an increasing linear effect on the n6:n3 ratio. Crude glycerin can replace corn without compromising tissue composition and quality traits of longissimus muscle. The inclusion of up to 7.5% crude glycerin (dry matter basis) in the diet for Pantaneiro lambs improves the nutritional aspects of fat...(AU)

O objetivo foi avaliar a composição tecidual, as características qualitativas e o perfil de ácidos graxos do Longissimus de cordeiro alimentados com teores crescentes de glicerina bruta (GB) na dieta. Foram utilizados 24 cordeiros machos, não castrados, distribuídos em delineamento inteiramente casualizado, com quatro tratamentos e seis repetições. Os tratamentos testados foram 0; 2,5; 5,0 e 7,5% de inclusão de GB na matéria seca da dieta em substituição ao milho. Os animais foram abatidos quando atingiram escore de condição corporal entre 2,5 e 3,0. Após o resfriamento das carcaças, o lombo foi retirado e utilizado para a determinação da composição tecidual, e o músculo Longissimus utilizado para determinação das características qualitativas. Os diferentes teores de glicerina bruta não influenciaram os pesos e rendimentos dos tecidos, e as características qualitativas do Longissimus. O teor de extrato etéreo apresentou efeito linear crescente. Houve efeito quadrático para o ácido graxo C17:0. O ácido graxo C18:1 n-9c e C18:3 n-3 diminuiu linearmente. Houve efeito quadrático para o total de ácidos graxos insaturados e efeito linear decrescente para os ácidos graxos n-3. A relação ácidos graxos insaturados:saturados apresentou efeito linear decrescente e houve efeito linear crescente para a relação n6:n3. A glicerina bruta pode ser utilizada em substituição ao milho na dieta de cordeiros sem ocasionar prejuízos na composição tecidual e características qualitativas do Longissimus. A inclusão de glicerina bruta até 7,5% da matéria seca na dieta para cordeiros Pantaneiros melhora os aspectos nutricionais de gordura...(AU)

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The objective of this study was to evaluate the tissue composition, quality traits and fatty acid profile of longissimus muscle of lambs fed increasing levels of crude glycerin. Twenty-four intact male lambs were allocated in a completely randomized design with four treatments and six replicates. The treatments consisted of the replacement of corn with 0, 2.5, 5.0 and 7.5% crude glycerin (dry matter basis) in the diet. The animals were slaughtered when they reached a body condition score of 2.5 to 3.0. After cooling the carcasses, the meat was removed for the determination of tissue composition and longissimus muscle for the evaluation of quality characteristics. The different crude glycerin levels did not affect tissue weight or yield, or the qualitative characteristics of longissimus muscle. An increasing linear effect was observed for ether extract. There was a quadratic effect on C17:0 fatty acids, and C18:1 n-9c and C18:3 n-3 fatty acids decreased linearly. A quadratic effect was observed for total unsaturated fatty acids and a linear decreasing effect for n-3 fatty acids. The unsaturated:saturated fatty acid ratio decreased linearly and there was an increasing linear effect on the n6:n3 ratio. Crude glycerin can replace corn without compromising tissue composition and quality traits of longissimus muscle. The inclusion of up to 7.5% crude glycerin (dry matter basis) in the diet for Pantaneiro lambs improves the nutritional aspects of fat...

O objetivo foi avaliar a composição tecidual, as características qualitativas e o perfil de ácidos graxos do Longissimus de cordeiro alimentados com teores crescentes de glicerina bruta (GB) na dieta. Foram utilizados 24 cordeiros machos, não castrados, distribuídos em delineamento inteiramente casualizado, com quatro tratamentos e seis repetições. Os tratamentos testados foram 0; 2,5; 5,0 e 7,5% de inclusão de GB na matéria seca da dieta em substituição ao milho. Os animais foram abatidos quando atingiram escore de condição corporal entre 2,5 e 3,0. Após o resfriamento das carcaças, o lombo foi retirado e utilizado para a determinação da composição tecidual, e o músculo Longissimus utilizado para determinação das características qualitativas. Os diferentes teores de glicerina bruta não influenciaram os pesos e rendimentos dos tecidos, e as características qualitativas do Longissimus. O teor de extrato etéreo apresentou efeito linear crescente. Houve efeito quadrático para o ácido graxo C17:0. O ácido graxo C18:1 n-9c e C18:3 n-3 diminuiu linearmente. Houve efeito quadrático para o total de ácidos graxos insaturados e efeito linear decrescente para os ácidos graxos n-3. A relação ácidos graxos insaturados:saturados apresentou efeito linear decrescente e houve efeito linear crescente para a relação n6:n3. A glicerina bruta pode ser utilizada em substituição ao milho na dieta de cordeiros sem ocasionar prejuízos na composição tecidual e características qualitativas do Longissimus. A inclusão de glicerina bruta até 7,5% da matéria seca na dieta para cordeiros Pantaneiros melhora os aspectos nutricionais de gordura...

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Objetivou-se com este trabalho estimar o bem-estar de suínos a partir de registros de sua vocalização, durante alojamento em granja comercial. Foram utilizados 150 suínos machos castrados, distribuídos aleatoriamente em cinco baias. Os suínos foram submetidos a diferentes situações de estresse: sede (sem acesso a água), fome (sem acesso ao alimento), estresse térmico (Índice de temperatura e umidade - ITU >74). Para o tratamento controle, os animais foram mantidos em situação de conforto, com acesso a alimento e água, e ambiente com ITU <70. Foram registrados os sinais acústicos a cada 30 minutos, durante período ininterrupto de três horas, totalizando seis coletas para cada situação de estresse. Os sinais foram digitalizados a uma frequência de até 44.100Hz, por um período de 3 minutos. Posteriormente, os áudios foram analisados pelo software Praat(r) 5.1.19. Os atributos gerados a partir desse software foram a energia do sinal (Pa²*s), amplitude máxima e amplitude mínima (Pa), a frequência de picht (Hz), a intensidade sonora (dB) e quatro níveis de formantes (F1; F2; F3 e F4), também chamados de harmônicas (Hz). Verificou-se que, dependendo do estímulo estressor e de sua duração, os atributos acústicos energia e intensidade do sinal, frequência de pitch e as formantes 2 e 4 apresentaram diferenciação. Os atributos sonoros da vocalização de suínos variam de maneira distinta em função do tipo e duração do estímulo estressante, funcionando, quando associados, como ferramenta eficiente para quantificar o grau de estresse dos animais.

This work aimed to estimate the welfare of pigs using their vocalization records during rearing in a commercial swine farm. A total of 150 barrow pigs were randomly distributed into five pens. Pigs were exposed to different stressful situations: Thirst (no access to water), hunger (no access to the food), thermal stress (Temperature and Humidity Index - THI >74). For the control treatment, the animals were kept in a situation of comfort, with full access to food and water, and environment THI <70. Acoustic signals were recorded every 30 minutes during a continuous period of three hours, totaling six samples for each stress exposure. The signals were digitized at a frequency of up to 44,100 Hz, for a period of 3 minutes. Later the audios were analyzed using the Praat (r) 5.1.19 software. The attributes generated from this software were the signal energy (Pa² * s), the maximum amplitude and the minimum amplitude (Pa), the frequency of pitch (Hz), the sound intensity (dB) and four levels of formants (F1, F2, F3 and F4), also called harmonics (Hz). It was found that depending on the acoustic attributes, the stressor stimuli and its duration indicate energy and signal strength, frequency of pitch and formants 2 and 4 showed differentiation. The sound attributes of the pig vocalization varied in different ways depending on the type and duration of the stressful exposure, functioning as an efficient tool to quantify the degree of animal degree.

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Objetivou-se com este trabalho estimar o bem-estar de suínos a partir de registros de sua vocalização, durante alojamento em granja comercial. Foram utilizados 150 suínos machos castrados, distribuídos aleatoriamente em cinco baias. Os suínos foram submetidos a diferentes situações de estresse: sede (sem acesso a água), fome (sem acesso ao alimento), estresse térmico (Índice de temperatura e umidade - ITU >74). Para o tratamento controle, os animais foram mantidos em situação de conforto, com acesso a alimento e água, e ambiente com ITU <70. Foram registrados os sinais acústicos a cada 30 minutos, durante período ininterrupto de três horas, totalizando seis coletas para cada situação de estresse. Os sinais foram digitalizados a uma frequência de até 44.100Hz, por um período de 3 minutos. Posteriormente, os áudios foram analisados pelo software Praat(r) 5.1.19. Os atributos gerados a partir desse software foram a energia do sinal (Pa²*s), amplitude máxima e amplitude mínima (Pa), a frequência de picht (Hz), a intensidade sonora (dB) e quatro níveis de formantes (F1; F2; F3 e F4), também chamados de harmônicas (Hz). Verificou-se que, dependendo do estímulo estressor e de sua duração, os atributos acústicos energia e intensidade do sinal, frequência de pitch e as formantes 2 e 4 apresentaram diferenciação. Os atributos sonoros da vocalização de suínos variam de maneira distinta em função do tipo e duração do estímulo estressante, funcionando, quando associados, como ferramenta eficiente para quantificar o grau de estresse dos animais(AU)

This work aimed to estimate the welfare of pigs using their vocalization records during rearing in a commercial swine farm. A total of 150 barrow pigs were randomly distributed into five pens. Pigs were exposed to different stressful situations: Thirst (no access to water), hunger (no access to the food), thermal stress (Temperature and Humidity Index - THI >74). For the control treatment, the animals were kept in a situation of comfort, with full access to food and water, and environment THI <70. Acoustic signals were recorded every 30 minutes during a continuous period of three hours, totaling six samples for each stress exposure. The signals were digitized at a frequency of up to 44,100 Hz, for a period of 3 minutes. Later the audios were analyzed using the Praat (r) 5.1.19 software. The attributes generated from this software were the signal energy (Pa² * s), the maximum amplitude and the minimum amplitude (Pa), the frequency of pitch (Hz), the sound intensity (dB) and four levels of formants (F1, F2, F3 and F4), also called harmonics (Hz). It was found that depending on the acoustic attributes, the stressor stimuli and its duration indicate energy and signal strength, frequency of pitch and formants 2 and 4 showed differentiation. The sound attributes of the pig vocalization varied in different ways depending on the type and duration of the stressful exposure, functioning as an efficient tool to quantify the degree of animal degree(AU)

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Objetivou-se avaliar desempenho, características das carcaças e qualidade da carne de cordeiros mestiços Suffolk, alimentados com dietas contendo gordura protegida. Foram utilizados 18 cordeiros machos, não castrados, com 18,8 ± 2,1 kg e média de idade de 70 dias. Os animais permaneceram confinados por 63 dias recebendo dietas contendo 0%, 4,2% e 5,8% de gordura protegida e foram abatidos com 34,8 ± 5,2 kg. O delineamento experimental foi inteiramente casualisado e os resultados foram analisados por regressão. Observou-se efeito quadrático do teor de gordura protegida na dieta para ganho de peso médio diário e ingestão de proteína bruta, com o ponto de máximo para o teor de 4,2%. Houve efeito linear crescente para ingestão de extrato etéreo. Não houve efeito do teor de gordura protegida nas dietas sobre as características de carcaça. Houve efeito quadrático para força de cisalhamento, com maior valor (3,75 kg) para a carne dos animais que receberam teor de 5,8 % de gordura protegida na dieta. O teor de extrato etéreo da carne também aumentou conforme a adição de gordura na dieta. Com base nos resultados, não se recomenda a utilização de gordura protegida em dietas com elevada proporção de concentrado para terminação de cordeiros em confinamento...

The objective of this study was to evaluate the performance and carcass and meat quality traits of crossbred Suffolk lambs fed diets containing protected fat. Eighteen uncastrated male lambs with a mean age of 70 days and weighing 18.8 ± 2.1 kg were used. The animals were kept in feedlots for 63 diets where they received diets containing 0%, 4.2% and 5.8% protected fat, and were slaughtered at 34.8 ± 5.2 kg. A completely randomized experimental design was used and the results were analyzed by regression. There was a quadratic effect of dietary protected fat content on average daily weight gain and crude protein intake, with a peak at a fat content of 4.2%. A linear increase was observed for ether extract intake. Dietary protected fat content had no effect on carcass traits. There was a quadratic effect on shear strength, with the highest value (3.75 kg) being observed for meat of animals fed the diet with 5.8% protected fat. The ether extract content of meat also increased with the addition of fat to the diet. On the basis of the results, we do not recommend the use of protected fat in diets containing a high proportion of concentrate for feedlot finishing of lambs...

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Objetivou-se avaliar desempenho, características das carcaças e qualidade da carne de cordeiros mestiços Suffolk, alimentados com dietas contendo gordura protegida. Foram utilizados 18 cordeiros machos, não castrados, com 18,8 ± 2,1 kg e média de idade de 70 dias. Os animais permaneceram confinados por 63 dias recebendo dietas contendo 0%, 4,2% e 5,8% de gordura protegida e foram abatidos com 34,8 ± 5,2 kg. O delineamento experimental foi inteiramente casualisado e os resultados foram analisados por regressão. Observou-se efeito quadrático do teor de gordura protegida na dieta para ganho de peso médio diário e ingestão de proteína bruta, com o ponto de máximo para o teor de 4,2%. Houve efeito linear crescente para ingestão de extrato etéreo. Não houve efeito do teor de gordura protegida nas dietas sobre as características de carcaça. Houve efeito quadrático para força de cisalhamento, com maior valor (3,75 kg) para a carne dos animais que receberam teor de 5,8 % de gordura protegida na dieta. O teor de extrato etéreo da carne também aumentou conforme a adição de gordura na dieta. Com base nos resultados, não se recomenda a utilização de gordura protegida em dietas com elevada proporção de concentrado para terminação de cordeiros em confinamento...(AU)

The objective of this study was to evaluate the performance and carcass and meat quality traits of crossbred Suffolk lambs fed diets containing protected fat. Eighteen uncastrated male lambs with a mean age of 70 days and weighing 18.8 ± 2.1 kg were used. The animals were kept in feedlots for 63 diets where they received diets containing 0%, 4.2% and 5.8% protected fat, and were slaughtered at 34.8 ± 5.2 kg. A completely randomized experimental design was used and the results were analyzed by regression. There was a quadratic effect of dietary protected fat content on average daily weight gain and crude protein intake, with a peak at a fat content of 4.2%. A linear increase was observed for ether extract intake. Dietary protected fat content had no effect on carcass traits. There was a quadratic effect on shear strength, with the highest value (3.75 kg) being observed for meat of animals fed the diet with 5.8% protected fat. The ether extract content of meat also increased with the addition of fat to the diet. On the basis of the results, we do not recommend the use of protected fat in diets containing a high proportion of concentrate for feedlot finishing of lambs...(AU)

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Laying hens reared under tropical conditions are usually under heat stress. Propolis is known for its pharmaceutical properties, such as increasing cell tolerance to hyperthermia, because of its antioxidants effects. This study aimed at evaluating the influence of different dietary propolis inclusion levels on the performance, egg quality, and bird surface temperature of layers. In this experiment 120 55-wk-old Isa Brown(r) layers were distributed according to a completely randomized experimental design into four treatments (0, 1, 2 and 3% dietary propolis inclusion levels), with three replicates of ten birds each. Performance and egg quality parameters, and birds' surface temperature were evaluated. Egg production, egg mass, feed intake, and feed conversion ratio were influenced by the treatments. Bird surface temperature was not affected by propolis dietary inclusion. The egg yolk color changed with the treatment (p 0.05) when brightness and red and yellow concentration were considered. Evaluators noted a slight difference among treatments during the sensory analysis. The use of propolis in the hens' diet did not improve performance and worsened the eggs' quality.

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Laying hens reared under tropical conditions are usually under heat stress. Propolis is known for its pharmaceutical properties, such as increasing cell tolerance to hyperthermia, because of its antioxidants effects. This study aimed at evaluating the influence of different dietary propolis inclusion levels on the performance, egg quality, and bird surface temperature of layers. In this experiment 120 55-wk-old Isa Brown(r) layers were distributed according to a completely randomized experimental design into four treatments (0, 1, 2 and 3% dietary propolis inclusion levels), with three replicates of ten birds each. Performance and egg quality parameters, and birds' surface temperature were evaluated. Egg production, egg mass, feed intake, and feed conversion ratio were influenced by the treatments. Bird surface temperature was not affected by propolis dietary inclusion. The egg yolk color changed with the treatment (p 0.05) when brightness and red and yellow concentration were considered. Evaluators noted a slight difference among treatments during the sensory analysis. The use of propolis in the hens' diet did not improve performance and worsened the eggs' quality.(AU)

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The aim of the study was to detect polymorphisms in the leptin gene and to determine the association of these polymorphisms with growth and carcass traits in Nellore cattle. The single nucleotide polymorphisms (SNPs) -1457 (AJ571671:g.-1457A>G) and A59V (AF536174.1:g. 321C>T), as well as the microsatellite BM1500 (3.9 kb downstream), were genotyped. The measures of body weight and ultrasound examinations (rib eye area, back, and rump fat thickness) were performed in 3 different periods of animal management. During the first period, the animals were fed with grass and mineralized salt ad libitum. In the second period, they received grass and concentrate, and in the third, only concentrate. After the slaughter of animals, data were collected for classification and typification of carcasses. No significant association was found between the variables assessed and SNP -1457. Conversely, SNP A59V was associated with rump fat thickness and muscle color post-slaughter. BM1500 was associated with rump fat thickness in the first period (pre-slaughter), subcutaneous fat thickness in the second, weight of the animals in the third, and length of the carcass after slaughter. These results suggest that SNP A59V and the microsatellite BM1500 might be useful for marker-assisted selection in Nellore cattle.

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Sheep of the Pantaneiro breed and seven other breeds, raised in the State of Mato Grosso do Sul, Brazil, were genotyped using eight microsatellite loci. The aim of the present study was to determine the genetic variability, phylogenetic relationship, and patterns of gene introgression and miscegenation among the animals surveyed, to obtain information about the genetic structure of locally adapted sheep in Mato Grosso do Sul. A total of 195 animals were used for genetic analysis. The Pantaneiro breed had the largest average number of alleles/locus (9.25), and higher allelic richness (6.95), while the Dorper population had the lowest values for these parameters (4.88 and 3.86, respectively). Analysis of genetic distance values and genetic structure between populations made it possible to characterize these animals with regard to distinct genetic groups. Average expected heterozygosity ranged from 0.72 (Pantaneiro) to 0.55 (Dorper), while average observed heterozygosity ranged from 0.63 (White Dorper) to 0.54 (Dorper). On the basis of the statistical parameters evaluated, it was possible to demonstrate that when compared to other populations, the Pantaneiro breed represented a reservoir of genetic diversity with rare and useful alleles for genetic improvement, emphasizing the importance of preserving the breed.

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Avaliou-se o efeito do período de descanso pré-abate e do sexo sobre a incidência de carne PSE (pale, soft, exudative) em suínos. Foram realizadas três visitas a abatedouro comercial, nas quais se mensurou o pH das carcaças (n=2128) aos 45 minutos após o abate, de lotes compostos por fêmeas, machos castrados cirurgicamente e machos imunocastrados e de lotes mistos (fêmeas e machos castrados cirurgicamente), submetidos a período de descanso que variou de duas a 16 horas. Carcaças com pH45≤5,8 foram classificadas como PSE, e com pH45>5,8 como normais. Em função do número de animais avaliados dentro de cada categoria, estimou-se a frequência de carne PSE. A incidência total de carne PSE foi de 10,1%, sendo maior nos lotes de animais imunocastrados (13,5%) quando comparados aos lotes de fêmeas (8,6%) ou de machos castrados cirurgicamente (8,5%). Períodos de descanso menores que seis horas e acima de 14 horas aumentaram a incidência de carne PSE. Período de descanso entre seis e oito horas minimizaram a ocorrência de carnes PSE.

Were evaluated the effect of lairage pre-slaughter and sex on the incidence of PSE (pale, soft and exudative) meat in pigs. There were three visits to a commercial slaughterhouse, in which the pH of carcasses (n=2128) was measured at 45 minutes after slaughter of lots consisting exclusively of females, males castrated surgically, males immunologically castrated and mixed lots (females and castrated surgically) underwent a resting time, and time between the shipment and slaughter ranged from two to 16 hours. Carcasses with pH45≤5.8 were classified as PSE and with pH45>5.8 as normal. Depending on the number of animals evaluated in each category we estimated the frequency of PSE. The overall incidence of PSE meat was 10.1%, higher in lots of animals immunocastrated (13.5%) compared to lots of females (8.6%) or castrated males (8.5%). Resting time of less than six hours and up to 14 hours increased the incidence of PSE meat. Resting time between six and eight hours minimized the occurrence of PSE meat.

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Buffaloes are generally raised in Brazil without milk-recording programs, and thus without genetic evaluations of any of their traits. This study evaluated the economic impacts of three different selection strategies on buffalo populations and the evolution of genetic trends, genetic variances and inbreeding coefficients resulting from each of them. The selection strategies used were as follows: (i) random selection; (ii) phenotypic selection; and (iii) progeny testing (PT). As the numbers of herds enrolled in milk-recording programs increased, phenotypic selection and PT strategies increased both monetary benefits and genetic trends. The extra costs of implementing milk recording (MR) and PT procedures were exceeded by the income resulting from better buffalo performance. Progeny testing is known to result in beneficial genetic trends and the use of artificial insemination promoted better distributions of genetic material into herds that were not enrolled in milk-recording programs. Phenotypic selection and PT increased mean milk production--a key factor in profitability. Inbreeding levels remained stable with phenotypic selection, even as the numbers of MR herds increased. Increases in the numbers of sires that were evaluated reduced the mean inbreeding coefficient in PT. Increasing the number of herds enrolled in milk-recording programs resulted in increased numbers of sires needed for PT, but this did not increase the inbreeding coefficient. In summary, phenotypic selection and PT strategies appear to be economically viable for buffalo husbandry in south-eastern Brazil under current (2007-2008) economic conditions and should be encouraged.

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RESUMO

Avaliou-se o efeito do período de descanso pré-abate e do sexo sobre a incidência de carne PSE (pale, soft, exudative) em suínos. Foram realizadas três visitas a abatedouro comercial, nas quais se mensurou o pH das carcaças (n=2128) aos 45 minutos após o abate, de lotes compostos por fêmeas, machos castrados cirurgicamente e machos imunocastrados e de lotes mistos (fêmeas e machos castrados cirurgicamente), submetidos a período de descanso que variou de duas a 16 horas. Carcaças com pH45≤5,8 foram classificadas como PSE, e com pH45>5,8 como normais. Em função do número de animais avaliados dentro de cada categoria, estimou-se a frequência de carne PSE. A incidência total de carne PSE foi de 10,1%, sendo maior nos lotes de animais imunocastrados (13,5%) quando comparados aos lotes de fêmeas (8,6%) ou de machos castrados cirurgicamente (8,5%). Períodos de descanso menores que seis horas e acima de 14 horas aumentaram a incidência de carne PSE. Período de descanso entre seis e oito horas minimizaram a ocorrência de carnes PSE.(AU)

Were evaluated the effect of lairage pre-slaughter and sex on the incidence of PSE (pale, soft and exudative) meat in pigs. There were three visits to a commercial slaughterhouse, in which the pH of carcasses (n=2128) was measured at 45 minutes after slaughter of lots consisting exclusively of females, males castrated surgically, males immunologically castrated and mixed lots (females and castrated surgically) underwent a resting time, and time between the shipment and slaughter ranged from two to 16 hours. Carcasses with pH45≤5.8 were classified as PSE and with pH45>5.8 as normal. Depending on the number of animals evaluated in each category we estimated the frequency of PSE. The overall incidence of PSE meat was 10.1%, higher in lots of animals immunocastrated (13.5%) compared to lots of females (8.6%) or castrated males (8.5%). Resting time of less than six hours and up to 14 hours increased the incidence of PSE meat. Resting time between six and eight hours minimized the occurrence of PSE meat.(AU)

Assuntos

RESUMO

The aim of the present study was to estimate the index and individual responses to selection for milk (MY), fat (FY) and protein (PY) yields for different breeding goals for two commercial buffalo milk production systems in São Paulo State characterized by: 1) all milk produced is sold to the industry (MILK) and 2) all milk produced is used in the mozzarella cheese-making process at the farm (MOZZARELLA). The current payment policy is based exclusively on milk volume. The mozzarella price refers to the wholesale selling price. Index responses to selection (IR) were calculated for three different breeding goals (BG): 1) MY exclusively (BG(1)); 2) FY + PY (BG(2)) and 3) MY + FY + PY (BG(3)). IR for the MILK system were 41.79 US dollars (BG(1)), 5.91 US dollars (BG(2)) and 38.22 US dollars (BG(3)). For the MOZZARELLA system, IR were 179.50 US dollars (BG(1)), 262.85 US dollars (BG(2)) and 402.41 US dollars (BG(3)). The results suggest that for the present circumstances, selection for milk components is not advantageous when milk is produced for sale to the industry. However, when mozzarella making is added to the system, the selection for components and milk volume is the most economically beneficial.

Assuntos

RESUMO

The aim of the present study was to estimate the index and individual responses to selection for milk (MY), fat (FY) and protein (PY) yields for different breeding goals for two commercial buffalo milk production systems in São Paulo State characterized by: 1) all milk produced is sold to the industry (MILK) and 2) all milk produced is used in the mozzarella cheese-making process at the farm (MOZZARELLA). The current payment policy is based exclusively on milk volume. The mozzarella price refers to the wholesale selling price. Index responses to selection (IR) were calculated for three different breeding goals (BG): 1) MY exclusively (BG(1)); 2) FY + PY (BG(2)) and 3) MY + FY + PY (BG(3)). IR for the MILK system were 41.79 US dollars (BG(1)), 5.91 US dollars (BG(2)) and 38.22 US dollars (BG(3)). For the MOZZARELLA system, IR were 179.50 US dollars (BG(1)), 262.85 US dollars (BG(2)) and 402.41 US dollars (BG(3)). The results suggest that for the present circumstances, selection for milk components is not advantageous when milk is produced for sale to the industry. However, when mozzarella making is added to the system, the selection for components and milk volume is the most economically beneficial.

Assuntos