Sabrina Endo Takahashi

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, distribuidos em delineamento, em blocos ao acaso, com esquema fatorial 4×2 (quatro linhagens, sendo uma delas comercial (Ross-308) e as demais especificas para a producao colonial (Caipirinha, Pescoco Pelado e Paraiso Pedres) e dois sistemas de criacao (confinado e com acesso a piquete), com quatro repeticoes de 50 aves cada. A racao nao continha promotores quimicos de crescimento e produtos de origem animal. Avaliaram-se o ganho de peso, o consumo de racao, a conversao alimentar, a mortalidade e os rendimentos de carcaca e das partes (peito, pernas, asas e dorso) aos 56, 63, 70, 77 e 84 dias de idade. O comprimento e a porcentagem (em relacao ao peso vivo) dos intestinos e o peso e a porcentagem (em relacao ao peso vivo) do figado, moela e pâncreas foram avaliados aos 84 dias de idade. Houve efeito (P<0,05) da linhagem para as caracteristicas de desempenho e da linhagem e do sexo para rendimentos da carcaca e das partes, assim como para as caracteristicas do sistema digestorio (P<0,05). O sistema de criacao nao influenciou as caracteristicas avaliadas.

Probiotic and prebiotic utilization in diets for free-range broiler chickens

This work aimed to evaluate the effects of probiotic associated to prebiotic on performance, carcass and cut yields, qualitative traits of meat, development and score of lesions due to coccidiosis in digestive tract of broiler chickens raised in a free-range system during 85 days. One thousand, six hundred and ninety-six day-old male broiler chicks from naked-neck ISA S757-N Label Rouge line were used in a randomized block design with factorial scheme of 4x2 and four repetitions. The effect of four additive (1 - biologic promoter + coccidiosis vaccine; 2 - biologic promoter + anti-coccidiosis; 3 - chemical promoter + coccidiosis vaccine; 4 - chemical promoter + anti-coccidiosis) and two breeding systems from 35th day of age (one with no-access to pasture or confined and the other with free-access to pasture or semi-confined) on performance parameters, carcass and cut yields, qualitative meat traits, coccidiosis development and lesions in digestive tract were evaluated. There was effect (p<0.05) of additives only on sensorial analysis (meat quality) and percentage of large intestine. Breeding systems affected (p<0.05) live weight (LW) and LW gains, being the better results observed in semi-confined 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.

Farelo de Girassol na Alimentação de Frangos de Corte em Diferentes Fases de Desenvolvimento

The aims of this work were to know the best age to feed poultry with sunflower meal (SM), to determine the best percentage of SM to feed animals in different ages and to evaluate economicall viability of SM as a feeding for poultry ration. In this experiment 480 three days old chicks were distributed in a randomized design. The experimental treatments consisted in rations with different percentages of SM (0, 4, 8 and 12%) and birds with different ages (I1= 3-21 days, I2=21-35 days and I3= 36-42 days of age). The treatments were: T1= 0% of SM inclusion on the rations at ages I1, I2 and I3; T2= 4% at ages I1, I2 and I3; T3= 8% at ages I1, I2 and I3, T4= 12% at ages I1, I2 and I3, T5=0% at age I1 and 4% at ages I2 and I3, T6=0% at age I1 and 8% at ages I2 and I3 ; T7= 0% at age I1 and 12% at ages I2 and I3, T8= 0% at ages I1, I2 and 4% at age I3, T9= 0% at ages I1, I2 and 8% at age I3; e T10= 0% at ages I1, I2 and 12% at age I3. Statistical analyses were carried out in factorial schemes 4x2, 7x2 and 10x2 to evaluate characteristic weight gain, feed intake and feed conversion rate at 3-21, 3-35 and 3-42 days, respectively. There were no treatments effects on weight gain and on feed intake in the birds age. At 3-35 days of age, treatments T1 and T7 provided respectively the best and the worst feed conversion rate. The lowest production cost was obtained when the animals were fed at treatment T8.

Comparison of techniques for tibial dyschondroplasia assessment in broiler chickens

This study was carried out at Faculdade de Medicina VeterinAEria e Zootecnia, Universidade Estadual Paulista, Botucatu, SP, Brazil, with the objective of evaluating the efficacy of four techniques in the assessment of tibial dyschondroplasia lesions in broiler chickens. Four hundred Cobb male chicks were reared from 1 to 39 days of age. At 39 days, forty birds were selected and tibial dyschondroplasia status was assessed by four different techniques: evaluation using the lixiscope, macroscopic examination, histological examination and bone mineral density assessment using optical radiographic densitometry. The efficacy of each technique to assess dyschondroplasia lesions in the tibial growth plate was determined in comparison to histology, which was considered to be 100% efficient. The correlation results between lixiscope analysis and histology were poor. Macroscopic scores and densitometry readings were highly correlated with histology scores, and it is considered that these techniques reliably reproduce the status of the growth plate.

Chicken Meat Quality as a Function of Fasting Period and Water Spray

This study aimed at evaluating the effect of different fasting periods and water spray during lairage on the quality of chicken meat. A number of 300 male Ross broilers were reared up to 42 days of age, and submitted to four pre-slaughter fasting periods (4, 8, 12, and 16 hours) and sprayed with water or not during lairage. Deboned breast meat was submitted to the following analysis: pH, color, drip loss, water retention capacity, cooking loss, and shear force. There was a significant effect (p≤0.05) of fasting period on meat luminosity was significantly different, with the highest value obtained for 4-hour fasting, whereas no difference was found among the other fasting periods. Meat pH values were different among fasting periods when birds received water spray, with birds fasted for 4, 8, and 12 hours of fasting presenting lower meat pH values (5.87, 5.87, and 6.04, respectively). The interaction between fasting period and water spray influenced meat drip loss and cooking loss, with birds fasted for 16h and not receiving water spray presenting higher drip loss (4.88) and higher cooking loss (28.24) as compared to the other birds. Fasting period affects meat quality, and very short periods (4h) impair meat quality.

Qualidade físico-química e sensorial da carne de peito de matrizes pesadas de descarte

The aim of this research was evaluate the meat quality broiler breeder hens: pH, color, R value, drip loss, water holding capacity, water absorption capacity, emulsion capacity, cooking loss, shear force and sensorial analysis. The breast meat of broiler hens presents means values for pH, R value, drip loss and L* value parameter of 5.70, 1.43, 2.00 and 50.11, respectively. The means value for water retention capacity, water absorption capacity, cooking loss and shear force, were 77, 58, 18% e 4.94kgf cm-2 respectively. For sensory analysis, the meat of broiler hen present lower tenderness intensity (6.9), lower succulence (3.4), more elasticity, rubbery and swallowing difficulties. The meat of broiler hens presented good technology quality characteristics that make it possible to be used as meat for elaborated industry.

Digestibility of feeds containing sorghum, with and without tannin, for broiler chickens submitted to three room temperatures

The traditional method of total excreta collection was applied, using 30 to 40 day old male Ross 308 broiler chickens. One hundred and eight broiler chickens were used, randomly assigned to a 3x3 factorial experimental design. The room temperatures were 14 C (cold), 25 °C (thermoneutral) and 32 °C (hot) and the three diets were 100% maize, 100% sorghum with tannin and 100% sorghum without tannin, with four replicates of each. The digestibility coefficients for the dry matter, crude protein, crude fibre, neutral detergent fibre, acid detergent fibre, ether extract, mineral matter and nitrogen-free extract were determined. It was observed that all the digestibility coefficients were higher in the hot chamber and lower in the cold chamber, and that these values tended to be higher for maize.

Study on the bone mineral density of broiler suffering femoral joint degenerative lesions

An experiment was carried out with male and females broilers of two different commercial breeds to evaluate bone mineral density of the right femur head. A number of 600 one-day-old broilers were raised in an experimental poultry house up to 42 days of age at the School of Veterinary Medicine and Animal Science of UNESP, Botucatu, Brazil. After slaughter, three males and three females in each breed in each of the established gross scores were selected. Their femora heads were submitted to gross examination, and subsequently the thighs were submitted to the Veterinary Hospital for radiographic analysis. Femora were also submitted to bone resistance, Seedor index, and dry matter content analyses. All these bone quality characteristics were different between males and females, independent of breed. Breeds presented similar behavior. It was possible to establish correlations between bone quality parameters, and confidence intervals for bone mineral density values, correlating them to femoral degeneration score, which allows characterizing femoral head lesions by radiographic optical densitometry.

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.