Desenvolveu-se este experimento com o objetivo de determinar a exigência nutricional de treonina para poedeiras leves e semipesadas no período de 21 a 36 semanas. Foram utilizadas 576 aves, 288 poedeiras leves e 288 semipesadas, durante quatro períodos experimentais de 28 dias cada. O delineamento experimental foi inteiramente casualizado em esquema fatorial 6 x 2 (níveis x marcas), com seis repetições e oito aves por unidade experimental. Os tratamentos consistiram em uma ração basal contendo 14,2% de proteína bruta, suplementada com cinco níveis de L-treonina (0,025; 0,050; 0,075; 0,100; e 0,125%), resultando em um total de 0,510; 0,535; 0,560; 0,585; 0,610; e 0,635% de treonina. O desempenho produtivo e a qualidade interna dos ovos foram avaliados. Consumo de ração, produção de ovos massa de ovos e o ganho de peso foram superiores para as poedeiras semipesadas. A produção e qualidade interna dos ovos, a conversão alimentar e o ganho de peso não foram influenciados pelos níveis de treonina utilizados. O nível de 0,510% de treonina, que corresponde a 515 mg/ave/dia (0,423% de treonina digestível) e 535 mg/ave/dia (0,440% de treonina digestível), foi suficiente para atender, satisfatoriamente, o desempenho e a qualidade interna dos ovos das poedeiras leves e semipesadas, respectivamente, para as características avaliadas.

RESUMO -Foram utilizadas 216 leitoas híbridas comerciais, da mesma linhagem genética, com alto potencial para deposição de carne magra na carcaça com peso médio inicial de 66,3 ± 4,24 kg e final de 95,5 ± 2,05 kg, para avaliar o efeito de níveis de lisina da dieta. Os animais foram distribuídos em delineamento experimental de blocos ao acaso, com quatro tratamentos, 27 repetições e dois animais por unidade experimental. Os tratamentos corresponderam a dietas isoenergéticas, com diferentes níveis de lisina total (0,80; 0,90; 1,00; e 1,10%), obtidos por alterações nas proporções de milho e farelo de soja da dieta. Não foi observado efeito dos tratamentos sobre o ganho de peso diário, a taxa de crescimento em músculo e conversão alimentar em músculo. Houve efeito quadrático dos tratamentos sobre o consumo de dieta, que reduziu até o nível estimado de 0,95%, e a conversão alimentar, que melhorou até o nível de 0,97% de lisina. Observou-se efeito linear dos níveis de lisina sobre a taxa de deposição de proteína, que aumentou, e sobre a taxa de deposição de gordura, que reduziu com o aumento dos níveis de lisina na dieta. Não foi verificado efeito dos tratamentos sobre as características de comprimento de carcaça, a espessura de toucinho na região entre a última e a penúltima vértebra lombar, a espessura de toucinho a 6,5 cm da linha dorsolombar (P 2 ), o rendimento de carcaça, o rendimento de carne magra, o rendimento de gordura e o rendimento de pernil. Concluiu-se que leitoas geneticamente selecionadas para alta taxa de deposição de carne magra exigem 0,97% de lisina total, correspondente ao consumo diário de 24,24 g de lisina e a 0,29% de lisina total/Mcal de EM, para melhor conversão alimentar. Para maior taxa de deposição de proteína, os dados indicam que a exigência está acima de 1,1% de lisina total.Palavras-chave: desempenho, fase de terminação, genótipo, lisina Lysine Levels for Gilts with High Genetic Potential for Lean Meat Gain from 65 to 95 kg ABSTRACT -Two hundred and sixteen crossbred gilts with high genetic potential for lean meat gain, with average initial weight of 66.3 ± 4.24 kg and final weight of 95.5 ± 2.05 kg, were used to evaluate the effect of lysine levels on animals performance in the finishing phase. A randomized block design was used with four treatments, 27 replicates and two animals per experimental unit. Treatments were constituted of isoenergy diets, with different levels of total lysine (0.80, 0.90, 1.00, and 1.10%), obtained by changes on corn and soybean meal proportion. There was no treatment effect on daily weight gain, muscle growth rate and muscle feed:gain ratio. There was a quadratic effect of dietary lysine on feed intake, which decreased up to the level of 0.95% lysine, and on feed:gain ratio, which increased up to the level of 0.97% lysine. There was a linear effect of lysine levels on protein and fat deposition rate, that respectively, increased and reduced with dietary lysine levels. There was no effect of treatments on carcass length, backfat thickness measured between ...

RESUMO -Para avaliar o efeito dos planos de nutrição, com base em níveis de lisina, sobre o desempenho e as características de carcaça de leitoas em terminação, utilizaram-se 96 leitoas híbridas comerciais de alto potencial genético para deposição de carne magra, com peso médio inicial de 65,93 ± 2,78 kg e final de 105,50 ± 2,18 kg. Os animais foram distribuídos em um delineamento experimental de blocos ao acaso, com quatro tratamentos (planos de nutrição), doze repetições e dois animais por baia, considerada a unidade experimental. Os tratamentos consistiram de planos nutricionais (estabelecidos por níveis seqüenciais de lisina) para duas diferentes faixas de peso, 65 a 95 kg e 95 a 105 kg. As rações foram isoenergéticas e os níveis de lisina foram obtidos variando a proporção entre o milho e o farelo de soja da ração. Não foi observado efeito dos tratamentos sobre o ganho de peso diário e sobre o consumo de ração diário. Houve efeito dos planos de nutrição sobre a conversão alimentar, sendo que o plano 3 propiciou melhora de 7,86% em relação ao plano 1, não diferindo dos demais. O consumo de lisina aumentou de acordo com a elevação dos níveis de lisina dos planos de nutrição. No plano 4, o consumo de lisina foi superior em 25,43%, em relação aos demais planos. Não houve diferença dos planos de nutrição sobre a taxa de conversão em músculo, conversão alimentar em músculo, comprimento de carcaça, espessura de toucinho na região entre a última e a penúltima vértebra lombar, a espessura de toucinho a 6,5 cm da linha dorso-lombar (P 2 ), o rendimento de carcaça, o rendimento de carne magra, o rendimento de gordura e sobre o rendimento de pernil. O estudo da análise econômica indicou que o plano de nutrição 2, proporcionou o melhor retorno econômico sobre o custo da ração. Portanto, conclui-se que o plano de nutrição 3 (1,00 -0,90% de lisina) proporcionou os melhores resultados de desempenho e características de carcaça. Palavras-chave: lisina, fase de crescimento, desempenho, genótipo Nutrition Plans for Gilts with High Genetic Potential for Lean Meat Gain from 65 to 105 kgABSTRACT -Ninety and six crossbred gilts with high genetic potential for lean meat gain, with average initial weight of 65.93 ± 2.78 kg and final weight of 105.50 ± 2.18 kg, were used to evaluate the effect of nutrition plans, based on the effects of lysine levels on the carcass traits of gilts in the finishing phase. A randomized block design, with four treatments, 12 replicates and two animals per box, used as experimental unit, was used. The treatments were constituted of nutritional plans (established by sequential lysine levels) for two different weights, from 65 to 95 kg and from 95 to 105 kg. The isoenergy diets and the lysine levels were obtained by changes on dietary corn and soybean proportion. There was no effect of treatments on daily weight gain and daily feed intake. There was effect of nutrition plans on feed:gain ratio, and the nutrition plan 3 showed an increase of 7.86% in relation to nutrition plan 1 and did not differ from the...

Two performance studies were conducted to investigate the effects of 3 different sources of Cu on production parameters of piglets. A total of 256 piglets weaned at 24 ± 2 d were randomly allocated into 4 treatments with 10 or 8 replicates per treatment of 4 or 3 piglets per pen in Exp. 1 and 2, respectively. The experimental period was divided into 3 feeding phases: Phase 1 (24 to 35 d), Phase 2 (36 to 49 d), and Phase 3 (50 to 70 d). Treatments included a Control group (fed 10 mg/kg of Cu from CuSO4), a group fed 160 mg/kg of either CuSO4 (CuSO4-160) or tri-basic copper chloride (TBCC), and a group fed Cu methionine hydroxy analogue chelated (Cu-MHAC) at 150, 80, and 50 mg/kg in Phases 1, 2, and 3, respectively. The methionine value of Cu-MHAC was accounted during diet formulation to achieve the same levels of methionine across treatments. Phases 1 and 2 diets contained 2,200 and 1,500 ppm of ZnO, respectively; and antibiotics were used as growth promoters. Performance parameters were analyzed as completely randomized block design, in which each experiment was considered as a block. In trial 2, blood serum and mucosal samples, from the fundic region of the stomach, were collected from 1 piglet per replicate at day 70 and tested for serum growth hormone levels (GH) and ghrelin mRNA expression, respectively. The contrast between Cu-MHAC vs. CuSO4-160 + TBCC showed that piglets fed Cu-MHAC exhibited better feed conversion ratio (FCR) in all feeding phases compared with feeding inorganic Cu (P < 0.05). Overall, feeding Cu-MHAC improved body weight (BW), BW gain, feed intake (FI), and FCR vs. Control diet fed piglets; yet, it improved BW and FCR vs. TBCC fed piglets, and improved BW, BW gain, and FI vs. CuSO4-160 fed piglets (P < 0.05). Feeding TBCC promoted similar performance than feeding CuSO4-160, regardless of age (P > 0.05). Both ghrelin expression and growth hormone serum levels were significantly increased by feeding Cu-MHAC vs. Control diet fed animals (P < 0.01). Feeding CuSO4-160 upregulated ghrelin expression vs. Control (P < 0.01) while GH serum levels and ghrelin expression did no change by feeding TBCC compared with Control diet fed animals (P > 0.05). It was concluded that feeding Cu-MHAC at the levels tested herein can improve growth performance of piglets beyond feeding 160 ppm of either CuSO4 or TBCC, which may be partially explained by the increased expression of ghrelin and GH serum levels.

This study was carried out to evaluate the effects of increasing levels of digestible methionine+cystine on performance and carcass composition of high genetic potential barrows for lean deposition. Sixty-four barrows with initial weight of 95.46 ± 1.09 kg were allotted to a completely randomized block design, with four levels of digestible methionine+cystine (0.427, 0.466, 0.504, and 0.545%, corresponding to the digestible methionine+cystine:digestible lysine ratios of 57.0, 62.0, 67.0 and 73.0%, respectively), with eight replicates, and two animals per experimental unit. Experimental diets and water were provided ad libitum until the end of the experimental period when pigs reached 125.21 ± 2.49 kg. Levels of digestible methionine+cystine did not affect daily intake, daily weight gain and feed conversion of the animals, but they affected daily intake of digestible methionine+cystine which increased linearly. Levels of digestible methionine+cystine did not affect carcass weight, meat amount, backfat thickness at P2, and daily meat deposition. The digestible methionine+cystine level of 0.427%, corresponding to the digestible methionine+cystine:lysine ratio of 57.0% and to a daily digestible methionine+cystine intake of 14.20 g/d, provides the best performance and carcass traits for high genetic potential barrows in the phase of 95 to 125 kg.

-In order to evaluate the effects of dietary digestible lysine levels on performance and carcass traits of two genetic lines of pigs selected for meat deposition, from 60 to 100 days of age, a total of 120 crossbred barrows, with initial average body weight of 25.42 ± 2.08 kg were used. Pigs were allotted in a complete randomized block design, within a 4 × 2 factorial arrangement (four digestible lysine levels: 0.90, 1.00, 1.10, and 1.20%, and two genetic lines: A and B), with five replicates and three pigs per pen, which was the experimental unit. There was no interaction between genetic and digestible lysine levels for any variable of performance and carcass traits assessed. There was also no effect of digestible lysine levels in feed intake, body weight gain, and feed conversion. Digestible lysine intake of pigs increased linearly with increasing digestible lysine levels in the diets. Except for carcass yield that increased quadratically up to 1.04% estimate level of digestible lysine, there was no effect of lysine levels on the other carcass traits assessed (loin and ham yield, and amount of meat in the carcass).The digestible lysine level of 0.90%, corresponding to an estimated daily intake of 19.10 g, meets the requirements of castrated male pigs selected for meat deposition from both genetic lines, from 60 to 100 days of age.

The purpose of this study was to assess the levels of available phosphorus (AP)

Cat food formulation should not only meet the animal's nutritional needs, but also take into