The objective of the present study was to evaluate nutritional plans for boars. Four hundred animals of 67 to 135 days of age and initial weight of 27.75±1.61 kg were distributed in a randomized block design with seven nutritional plans for boars (9.0-8.0; 9.0-9.0; 10.0-9.0; 10.0-10.0; 11.0-10.0; 11.0-11.0 and 12.0-11.0 g/kg of digestible lysine from 67 to 107 days and from 108 to 135 days, respectively) with four repetitions and a control plan for barrows (11.0-10.0 g/kg of digestible lysine) with eight repetitions and ten animals each. Uncastrated male swine presented better feed conversion; however they showed a lower marbling degree in relation to barrows, regardless of the nutritional plan. The nutritional plan that corresponds to the sequence of 11.0-10.0 g/kg of digestible lysine from the 67 to the 107 days and from the 108 to the 135 days, respectively, meets the nutritional needs of boars.

This experiment was conducted to determine the requirement of available phosphorus (aP) for pigs kept in hot environment. Seventy-two pigs (36 castrated males and 36 females) with initial weight of 15.10±0.31 kg were allotted in a completely randomized block design with six treatments (0.107, 0.214, 0.321, 0.428, 0.535, and 0.642% of aP), six replicates and two pigs (1 castrated male and 1 female) per experimental unit. Pigs were kept in a hot environment with temperature of 34.1±0.8 ºC. The levels of aP influenced the daily weight gain, which increased quadratically up to the estimated level of 0.477%, and feed conversion, which improved quadratically up to the estimated level of 0.457%. The levels of aP also influenced the content of phosphorus in the bone, which increased quadratically up to the estimated level of 0.529%. The available phosphorus requirement of 15- to 30-kg pigs kept in a hot environment, for the best results of daily weight gain, feed conversion and bone parameters are 0.477, 0.457, and 0.529%, corresponding to the estimated daily available phosphorus intakes of 4.75; 4.55 and 5.27 g, respectively.

Foram utilizadas 65 porcas (Large White x Landrace) com 217,36 ± 21,35 kg para avaliação de diferentes níveis de lisina total (0,950; 1,025; 1,100; 1,175 e 1,250%) na ração para a fase de 21 dias de lactação. Utilizou-se o delineamento experimental de blocos ao acaso, com cinco tratamentos e 13 repetições, sendo a porca considerada a unidade experimental. O consumo total de ração diário foi fixado entre os tratamentos. Os níveis de lisina da ração não influenciaram o peso das matrizes ao desmame, a perda de peso, a espessura de toucinho (ET) das matrizes, a variação na ET, a perda de gordura corporal, o número de leitões desmamados por leitegada e o intervalo desmama-estro. No entanto, foi verificada redução linear na perda de proteína corporal, em kg e em porcentagem, e na produção de leite diária das matrizes suínas com o aumento do nível de lisina na ração. O ganho de peso da leitegada foi influenciado, reduzindo de forma linear com os tratamentos. Os resultados obtidos neste estudo evidenciaram que, ao consumir menores quantidades de lisina, as matrizes mobilizaram suas reservas corporais protéicas para manutenção do desempenho produtivo. Entretanto, a quantidade de proteína mobilizada por estes animais (2,2 kg, correspondente a 6,45% da proteína corporal) não foi suficiente para influenciar os parâmetros produtivos e reprodutivos. O consumo diário de 45 g de lisina total, correspondente a 40 g de lisina digestível, atende às exigências para os desempenhos produtivo e reprodutivo de fêmeas suínas em lactação, enquanto o consumo estimado de 58,9 g de lisina total/dia, correspondente a 53,5 g/dia de lisina digestível, minimiza a perda de proteína corporal durante a lactação.

Sixty-five crossbred sows (Landrace x Large White) averaging 217.36 ± 21.35 kg were used to evaluate increasing dietary total lysine levels (0.950, 1.025, 1.100, 1.175, and 1.250%) during 21 days of lactation. The experiment was analyzed as a randomized block design, with five treatments, 13 replicates of one sow per experimental unit. The daily total feed intake was fixed for all treatments. The dietary lysine levels did not affect sow weight at weaning, body weight loss, backfat thickness (BT), BT change, body fat loss, number of weaned piglets per litter and weaning-to-estrus interval. However, there was a linear decrease on body protein loss expressed as kg and percentage and on daily milk production of sows, as the dietary lysine levels increased. The treatments affected litter weight gain, that decreased linearly. The results of this work showed that sows fed decreasing lysine levels retained significant amounts of body protein reserve to maintain their productive performance. However, the protein mobilization of these animals (2.2 kg corresponding to 6.45% of body protein loss) was not enough to affect the productive and reproductive performance. It was concluded that a daily total lysine intake of 45 g, correspondent of 40 g of digestible lysine meets the requirements for productive and reproductive performance of lactating sows and that they require 58.9 g of estimate total lysine/day, that corresponds to 53.5 g/day of digestible lysine to minimize body protein loss during the lactation.

Utilizaram-se 240 frangos de corte machos Hubbard com peso médio inicial de 689+5,27 g, mantidos de 22 a 42 dias de idade, em condições de estresse de calor (31,9+0,29ºC). Foi usado delineamento inteiramente casualizado, com cinco tratamentos (3000, 3075, 3150, 3225 e 3300 kcal de energia metabolizável/kg de ração), seis repetições e oito animais por unidade experimental. Avaliaram-se os efeitos de níveis de energia metabolizável (EM) sobre o desempenho, a qualidade de carcaça e as variáveis fisiológicas de frangos de corte alimentados de forma controlada (93% do consumo voluntário) com rações isoprotéicas. O ganho de peso e a conversão alimentar elevaram-se e o consumo de energia metabolizável aumentou linearmente, em razão do nível de EM das rações. Observou-se que as deposições de proteína e gordura na carcaça foram influenciadas de forma linear crescente, enquanto o peso absoluto da sobrecoxa apresentou variação quadrática. Os pesos absoluto dos pulmões e do coração e o relativo dos pulmões dos frangos de corte foram influenciados pelo nível de EM das rações. O nível de 3300 kcal de EM proporcionou os melhores resultados de desempenho, enquanto o de 3108 kcal resultou em maior deposição de proteína, com menor proporção de gordura na carcaça de frangos de corte mantidos em condições de estresse de calor.

Two hundred and forty male broilers, Hubbard strain, with average 689±5.27 g LW maintained, from 22 to 42 days of age under heat stress (31.9±0.29ºC) conditions were used. A completely randomized design, with five treatments (3000, 3075, 3150, 3225 and 3300 kcal metabolizable energy/kg of diet), six replicates and eight animals per experimental unit was used. The effects of different levels of metabolizable energy (ME) levels on the performance, carcass quality and physiological variables of broilers fed isoproteic diets, in a controlled way (ingesting 93% of the voluntary intake) were evaluated. The weight gain and feed:gain ratio improved and the metabolizable energy intake increased linearly in reason of the metabolizable energy level of the diet. The protein and fat carcass deposition increased linearly and the absolute weight of drumstick quadraticaly in function of the dietary metabolizable energy level. The broiler fed a 3232 kcal of ME showed the best performance; however those fed 3108 kcal diets had higher protein deposition with less proportion of fat in carcass of the broilers maintained under heat stress conditions.