Non-phytate phosphorus requirement for broilers from 8 to 21 days of age under heat stress conditions.

Two trials were conducted to determine the non-phytate phosphorus (nPP) requirement for broiler under heat stress. In both trials, birds were distributed in a completely randomized 4 × 2 factorial design with four nPP concentrations: 0.25, 0.35, 0.45, and 0.55%, and two Ca supply techniques: Ca fixed at 0.899% (CaF) or varying along with nPP aiming a 2:1 Ca to nPP ratio (CaV). Both trials had eight pens/treatment, with nine and five birds/pen for exp. 1 and exp. 2, respectively. nPP concentration had no effect on feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), nor fat deposition ratio (FDR). nPP levels showed a linear effect on protein deposition ratio (PDR) only for CaF diets. The nPP levels had a significant effect, regardless the technique adopted, on tibia phosphorus (TibP), which varied quadratically, on tibia calcium (TibCa) that increased quadratically and linearly, respectively, on CaF and CaV diets, and on tibia ash (TibAsh) that showed a quadratic effect for both. No effect was observed on Ca to P ratio in the tibia (TibCa:TibP). The nPP levels showed a linear increase effect over phosphorus intake (PI), phosphorus excreted (PE), and phosphorus retained (PR), and a linear decrease effect on phosphorus retention coefficient (PRC). Therefore, the nPP requirement for broilers from 8 to 21 days of age that provided better performance and bone variables were 0.250 and 0.484%, respectively, for CaF diets and 0.250 and 0.511%, respectively, for CaV diets.

Yeast extract plus blood plasma in diets for piglets from 36 to 60 days old / Extrato de levedura associado ao plasma sanguíneo sobre o desempenho de leitões dos 36 aos 60 dias

ABSTRACT: To evaluate inclusion levels and residual effects of diets containing yeast extract (YE) plus blood plasma (BP) on the performance of 36 to 60-days old piglets, 105 piglets were used (8.75±0.72kg), and they were distributed under a randomized block experimental design with five treatments (control - 2.0% BP; 1.0% BP plus 0.0, 1.0, 2.0, or 3.0% YE), seven repetitions, and three animals per experimental unit. Piglets were given experimental diets from 36 to 49 days of age. From 50 to 60 day of age, all piglets received the same diet. No effects from treatments (P>0.10) were observed on the performance variables from 36 to 49 day of age. From 50 to 60 day of age, an effect was observed from YE levels on the daily feed consumption (P<0.03), daily weight gain (p<0.01), and final weight (P<0.06), which increased quadratically up to 1.67, 1.67, and 1.55% YE levels, respectively. Piglets which were fed with the diet containing 1.0% BP + 2.0% YE were observed to have better feed conversion ratios (P<0.01) as compared to the control diet (2.0% BP). As it provides a better residual effect, the inclusion of 1.67% yeast extract may replace 50% of blood plasma in 36 to 49-days old piglet diets.

RESUMO: Para avaliar níveis de inclusão e o efeito residual de dietas contendo extrato de levedura (ExL) associado ao plasma sanguíneo (PS) sobre o desempenho de leitões dos 36 aos 60 dias, foram utilizados 105 leitões (8,75±0,72kg), distribuídos em delineamento experimental de blocos ao acaso com cinco tratamentos (controle - 2,0% de PS; 1,0% PS, associado ao 0; 1,0; 2,0 ou 3,0% de ExL), sete repetições e três animais por unidade experimental. As dietas experimentais foram fornecidas dos 36 aos 49 dias e, dos 50 aos 60 dias de idade, os animais passaram a receber dieta única para avaliar o efeito residual dos tratamentos experimentais. Não foram observados efeitos dos tratamentos (P>0,10) sobre as variáveis de desempenho dos 36 aos 49 dias de idade. Dos 50 aos 60 dias de idade, houve efeito dos níveis de ExL sobre o consumo de ração diário (P<0,03), ganho de peso diário (P<0,01) e peso final (P<0,06) que aumentaram de forma quadrática até os níveis de 1,67, 1,67 e 1,55% de ExL, respectivamente. Leitões alimentados com a dieta contendo 1,0% de PS + 2,0% de ExL apresentaram melhor (P<0,01) conversão alimentar em relação à dieta controle (2% de PS). Por proporcionar melhor efeito residual, a inclusão de 1,67% de extrato de levedura pode substituir 50% do plasma sanguíneo na dieta de leitões dos 36 aos 49 dias de idade.

Lysine requirement for growing-finishing immunocastrated male pigs.

Eighty boars (19.3 ± 2.49 kg) were vaccinated twice (100 and 128 days of age) against gonadotropin releasing hormone (Vivax™ vaccine), for a randomised block design study aiming to evaluate five digestible lysine (DLys) level treatments, with three phase-feeding per treatments (9-8-7; 10-9-8; 11-10-9; 12-11-10 and 13-12-11 g/kg) during the growing-finishing phases (54-100, 100-128 and 128-155 days of age, respectively). Pigs were fed their respective diets ad libitum from 54 to 155 days and weighed at 100, 128 and 155 days. Pig loin (Longissimus dorsi) area, loin depth and backfat thickness were measured by ultrasound at 100 and 155 days. Hot carcass weight, meat quantity and meat yield were measured at slaughter. From 54 to 100 days (pre-immunocastration), DLys levels linearly improved pig feed conversion and loin area, the level of DLys for minimum feed conversion and maximum loin area was 13 g/kg. However, DLys levels had no effect on the performance of boars from 54 to 128 days (pre-immunocastration), nor on the performance and carcass parameters of immunocastrated male pigs between 54 and 155 days. A sequence of diets containing 9, 8 and 7 g/kg of DLys fed from 54 to 100, 100 to 128 and 128 to 155 days, respectively, meet the requirement of growing-finishing immunocastrated male pigs.

Sequences of digestible lysine for gilts from 60 to 148 days of age / Sequências de lisina digestível para leitoas dos 60 aos 148 dias de idade

The experiment was conducted to evaluate five nutritional plans based on sequences of standardized ileal digestible lysine: 0.90-0.80-0.70, 1.00-0.90-0.80, 1.10-1.00-0.90, 1.20-1.10-1.00, and 1.30-1.20-1.10% fed to gilts from 60 to 99, 129 to 100, and 130 to 148 days of age, respectively. Eighty commercial hybrid gilts, selected for lean gain, with initial weight of 23.46±0.27kg were allotted in a randomized block design, with five treatments, eight replicates, and two pigs per experimental unit. No effect (P>0.05) of the nutritional plans was verified on daily feed intake, daily weight gain and feed conversion. The nutritional plans had no influence (P>0.05) on any of the carcass traits evaluated (carcass yield, meat amount, and meat yield). The nutritional plan of 0.90-0.80-0.70% standardized ileal digestible lysine fed to gilts from 60 to 99, 100 to 129, and 130 to 148 days of age, respectively, meets the standardized ileal digestible lysine requirements of gilts from 60 to 148 days of age.

O experimento foi conduzido com o objetivo de avaliar cinco planos de nutrição baseados em sequências de lisina digestível verdadeira: 0,90-0,80-0,70; 1,00-0,90-0,80; 1,10-1,00-0,90; 1,20-1,10-1,00 e 1,30-1,20-1,10%, fornecidos dos 60 aos 99, dos 100 aos 129 e dos130 aos 148 dias de idade, respectivamente. Foram utilizadas oitenta leitoas, híbridas comerciais, selecionadas para deposição e carne, com peso inicial de 23,46±0,27kg. Os animais foram distribuídos em delineamento de blocos ao acaso, com cinco tratamentos, oito repetições e dois animais por unidade experimental. Não houve efeito (P>0,05) dos planos nutricionais no consumo de ração diário, no ganho de peso diário e na conversão alimentar. Os planos nutricionais não influenciaram (P>0,05) nenhum dos parâmetros de característica de carcaça avaliados (rendimento de carcaça quente, quantidade de carne e rendimento de carne). O plano nutricional de lisina digestível verdadeira de 0,90-0,80-0,70% fornecido dos 60 aos 99, dos 100 aos dos 129 e 130 aos 148 dias de idade, respectivamente, atende às exigências de lisina digestível verdadeira de leitoas dos 60 aos 148 dias de idade.

Net energy for 60- to 120-kg pigs fed low-crude protein diets / Energia líquida para suínos dos 60 aos 120kg recebendo dietas com redução de proteína

Two experiments were conducted to determine the effects of dietary net energy content (NE) on performance and carcass traits of finishing barrows fed low-crude protein (CP) diets. Pigs (60.0±1.05kg, Exp. 1, 93.0±1.56kg, Exp. 2) were allotted in a randomized block design to 3 dietary treatments. Exp. 1 had 6 pens treatment-1 and Exp. 2 had 8 pens treatment-1 and all pens had 2 pigs. The treatments were: 199g kg-1 CP and 2566kcal kg-1 NE, 155g kg-1 CP and 2631kcal kg-1 NE, 155gk g-1 CP and 2566kcal kg-1 NE in Exp. 1, and 180g kg-1 CP and 2588kcal kg-1 NE, 145g kg-1 CP and 2638kcal kg-1 NE, 145g kg-1 CP and 2588kcal kg-1 NE, in Exp. 2. In Ep.1, except for average daily gain (ADG) there was no effect of dietary CP or NE on any other parameter evaluated. The diet with 155g kg-1 CP and 2566kcal kg-1 NE resulted in greatest ADG. In Exp. 2, the greatest results of ADFI and ADG were obtained with 145g kg-1 CP and 2588kcal kg-1 of NE. Pigs fed the diet with 180g kg-1 CP and 2588kcal kg-1 NE had less carcass meat. There was no effect of dietary CP or NE on backfat. The CP diet containing 2566kcal kg-1 NE resulted in greatest ADG of 60- to 95-kg barrows. For 95- to 120-kg barrows the diet with 145gk g-1 CP and 2588kcal kg-1 of NE resulted in greatest ADG and carcass meat.

Dois experimentos foram conduzidos para determinar os efeitos da energia líquida (EL) da ração no desempenho e nas características de carcaça de suínos, recebendo dietas com proteína bruta reduzida (PB). Os suínos (60,0±1,05kg, Exp. 1, 93,0±1,56kg, Exp. 2) foram distribuídos em delineamento de blocos casualizados, com três tratamentos. O Exp. 1 teve seis baias/tratamento e o Exp. 2 teve 8 baias/tratamento e todas as baias tiveram 2 animais. Os tratamentos foram: 199g kg-1 PB e 2566kcal kg-1 NE, 155g kg-1 PB e 2.631kcal kg-1 NE, 155g kg-1 PB e 2.566kcal kg-1 NE no Exp. 1, e 180g kg-1 PB e 2588kcal kg-1 NE, 145g kg-1 PB e 2638kcal kg-1 NE, 145g kg-1 de PB e 2588kcal kg-1 NE, no Exp. 2. No Exp.1, a ração com 155g kg-1 PB e 2566kcal kg-1 EL resultou em maior GPD. Não houve efeito dos níveis PB ou EL sobre os demais parâmetros. No Exp. 2, os melhores resultados de CRD e GDP foram obtidos com 145g kg-1 PB e 2588kcal kg-1 EL. Os suínos alimentados com a dieta com 180g kg-1 PB e 2.588kcal kg-1 NE apresentaram menor quantidade de carne na carcaça. Não houve efeito do conteúdo de PB ou EL da ração na espessura de toucinho. A ração contendo 155g kg-1 PB e 2.566kcal kg-1 NE resultou em maior GPD de suínos dos 60 aos 95kg. Dos 95 aos 120kg, a dieta com 145g kg PB e 2588kcal kg-1 EL resultou em maior GPD e carne na carcaça.

Thermoregulatory responses during thermal acclimation in pigs divergently selected for residual feed intake.

The objective of this study was to evaluate the performance and thermoregulatory responses during acclimation to high ambient temperature (Ta) of pigs from two lines selected for high (RFI(+)) or low (RFI(-)) residual feed intake with the hypothesis that RFI(-) pigs producing less heat would better tolerate high Ta. Pigs (50 kg initial body weight; 17 per line among which 10 of them were catheterized) were individually housed in a climatic-controlled room where Ta was maintained at 24.2 ± 0.4 °C during 7 days and thereafter at 30.4 ± 0.7 °C during 14 days. Irrespective of Ta, RFI(-) pigs had lower feed intake (ADFI) and similar average daily gain (ADG) than RFI(+) pigs. Whatever the line, ADFI, ADG, and feed efficiency decreased with increased Ta. Overall, the Ta increase resulted in an increase in rectal temperature (RT), skin temperature (ST), and respiratory rate (RR) within the first 24-48 h and, subsequently, in a decrease followed by stabilization. The RT decrease during acclimation occurred 24 h earlier in RFI(-) pigs than in RFI(+). Thyroid hormones and cortisol decreased at high Ta and it was similar in both lines. Based on performance and RT, ST, and RR responses, it seems that selection for low RFI tends to ameliorate pigs' tolerance to high Ta. Nevertheless, this selection does not induce significant differences between lines in endocrine and metabolite responses during thermal stress.

Lisina digestível para leitoas em fase de crescimento / Digestible lysine for growing gilts

Oitenta leitoas (24,2±1,52kg) com alto potencial genético para deposição de carne na carcaça foram distribuídas em experimento de blocos ao acaso para avaliar cinco níveis de lisina digestível (Ld) (9, 10, 11, 12 e 13g kg-1) durante a fase de crescimento (63 a 103 dias de idade). Os animais foram alojados em pares e alimentados à vontade. No início e ao final do período experimental, as leitoas foram pesadas e submetidas à análise de ultrassom para avaliação da área de olho de lombo (AOL) e espessura de toucinho (ET). Os níveis de Ld proporcionaram aumento linear (P<0,05) do ganho de peso diário (GPD) e, apesar dessa variação, não houve aumento no valor absoluto do GPD a partir do nível de 12g kg-1 de Ld. A conversão alimentar (CA) reduziu (P<0,01) de forma quadrática até o nível estimado de 11,9g kg-1 de Ld. A AOL das leitoas aumentou (P<0,05) de forma linear. No entanto, o modelo "Linear Response Plateau" foi o que melhor se ajustou aos dados, estimando em 12,5g kg-1 o nível a partir do qual ocorreu platô. Não foi verificada influência (P>0,05) dos níveis de Ld sobre o consumo de ração diário (CRD) e ET. Os níveis de 12,0 e 12,5g kg-1 de Ld na dieta, correspondentes, respectivamente, ao consumo de lisina digestível diário (CLdD), de 23,6 e 24,6g, proporcionam os melhores resultados de desempenho e área de olho de lombo de leitoas em fase de crescimento (63 aos 103 dias de idade).

Eighty gilts (24.2±1.52kg) with high genetic potential for lean gain were used in a randomized complete block design to evaluate five digestible lysine levels (9, 10, 11, 12 and 13g kg-1) during the growing phase (63 to 103 days of age). Gilts were housed in pair and fed their respective diets ad libitum. At the begging and the ending of the experimental period, gilts were weighed and scanned by ultrasound to measure loin area, as well as fat depth. The digestible lysine levels linearly increase (P<0.05) average daily gain and loin area of gilts in growing phase. However, there was no difference for average daily gain at levels above 12g kg-1 while the "Linear Response Plateau" model was that better fitted to the loin area data that stabilized in a plateau starting from the level of 12.5g kg-1. The feed:gain ratio was improved (P<0.01) quadratically until the estimated level of 11.9g kg-1 of digestible lysine. There was no effects (P>0.05) of the treatments on the fat depth and feed intake. The digestible lysine levels of 12 and 12.5g kg-1, corresponding to the intake of 23.6 e 24.6g dia-1, provide the best results of performance and loin area of growing gilts (63 to 103 days old).

Lisina digestível para suínos machos não castrados de alto potencial genético em fase de crescimento / Digestible lysine for pigs not castrated of high genetic potential in growth phase

Este estudo foi realizado com o objetivo de determinar a exigência de lisina digestível para suínos machos não castrados de alto potencial genético em fase de crescimento. Foram utilizados 320 machos não castrados e 80 castrados, com peso inicial de 27,75±1,61kg, distribuídos em delineamento experimental em blocos ao acaso composto por cinco tratamentos (0,90; 1,00; 1,10 e 1,20 por cento de lisina digestível para não castrados e 1,10 por cento de lisina digestível para castrados), oito repetições, com 10 animais cada. O aumento da concentração de lisina na dieta aumentou de forma linear (P<0,05) o peso final, consumo de lisina diário, ganho em peso diário e consumo de lisina por quilograma de ganho em peso e reduziu a conversão alimentar dos machos não castrados. Os tratamentos não influenciaram (P>0,05) o consumo de ração diário dos machos não castrados. Suínos castrados apresentaram maior (P<0,05) consumo diário de ração e pior (P<0,05) conversão alimentar em relação aos não castrados alimentados com as dietas contendo 1,00; 1,10 e 1,20 por cento de lisina. Machos castrados apresentaram consumo de lisina diário superior (P<0,05) aos não castrados alimentados com a dieta contendo 0,90; 1,00 e 1,10 por cento de lisina. Suínos castrados apresentaram menor (P<0,05) ganho de peso diário e peso final em relação aos não castrados consumindo a dieta contendo 1,20 por cento de lisina. Foi observado maior (P<0,05) consumo de lisina por quilograma de ganho em peso dos machos castrados em relação aos não castrados. Recomenda-se o mínimo de 1,20 por cento de lisina digestível na dieta de suínos machos não castrados de alto potencial genético em fase de crescimento.

This study was conducted to determine the digestible lysine requirement for non castrated pigs of high genetic potential in growth phase. It was used 320 not castrated and 80 castrated males, with initial weight of 27.75±1.61kg, distributed in a randomized block design consisting of five treatments (0.90, 1.00, 1.10 and 1.20 percent digestible lysine for not castrated and 1.10 percent digestible lysine for castrated males), eight replicates with ten animals each. The increase of lysine concentration in the diet increased linearly (P<0.05) the final weight, daily lysine intake, daily weight gain and lysine intake per kilogram of weight gain and reduced feed conversion of not castrated males. The treatments did not affected (P>0.05) daily feed intake of not castrated males. Castrated males had higher (P<0.05) daily feed intake and lower (P<0.05) feed conversion compared to not castrated fed diets containing 1.00, 1.10 and 1.20 percent lysine. Castrated males had higher daily lysine intake (P<0.05) than not castrated fed diets containing 0.90, 1.00 and 1.10 percent lysine. Castrated pigs had lower (P<0.05) daily gain and final weight in relation to non castrated consuming a diet containing 1.20 percent lysine. Castrated males had higher (P<0.05) lysine intake per kilogram of weight gain compared with not castrated. It is recommended a minimum of 1.20 percent lysine in the diet of not castrated male pigs with high genetic potential in growth phase.