ABSTRACT This study was conducted to evaluate nutritional plans of digestible phosphorus for barrows weighing between 30 and 100 kg. Eighty animals were distributed in a randomized block design with five nutritional plans containing 2.19-1.86-1.71, 2.57-2.23-2.09, 2.94-2.61-2.46, 3.32-2.99-2.84, and 3.70-3.36-3.32 g of digestible phosphorus kg−1 of diet, respectively, for the phases of 30 to 50 kg, 50 to 70 kg, and 70 to 100 kg, with eight replications and two barrows per experimental unit. The nutritional plans of digestible phosphorus had no effect on the final body weight, feed intake, daily weight gain, or feed conversion of barrows. The daily intake of digestible phosphorus increased with the dietary concentrations of digestible phosphorus. Of the carcass characteristics assessed, only muscle depth responded significantly to the highest concentration of digestible phosphorus, as assessed in barrows sequentially fed the 3.70-3.36-3.32 g kg−1 diet. The nutritional plans had no effect on backfat, rib eye area, or carcass lean tissue mass, percentage, and deposition. The nutritional plan containing 2.19-1.86-1.71 g kg−1 of digestible phosphorus meet the nutrient requirements for performance and carcass characteristics of barrows weighing from 30 to 100 kg.

RESUMO: Conduziu-se este estudo com o objetivo de avaliar níveis de energia líquida e ractopamina na dieta de suínos machos castrados em terminação dos 70 aos 100kg. Foram utilizados 150 suínos, com peso inicial de 70,80±3,84kg, distribuídos em delineamento de blocos ao acaso, em esquema fatorial 5x3, com cinco níveis de energia líquida (2.300, 2.425, 2.550, 2.675 e 2.800Kcal kg-1 de dieta) e três níveis de ractopamina (5, 10 e 20ppm kg-1 de dieta), cinco repetições e dois animais por unidade experimental. Não houve interação (P>0,05) entre os níveis de energia líquida e ractopamina. O aumento dos níveis de energia líquida das dietas proporcionou redução linear do consumo de ração e resultou em melhora linear da conversão alimentar. Não houve efeito (P>0,05) dos níveis de energia líquida no ganho de peso, peso final e nas características de carcaça. Recomenda-se o nível de 2.800Kcal de EL kg-1 de dieta para suínos de 70 a 100kg por melhorar a conversão alimentar, sem prejudicar as características de carcaça, independentemente do nível de ractopamina das dietas. A inclusão de ractopamina na dieta de suínos dos 70 aos 100kg não afeta o desempenho e não modifica as características quantitativas das carcaças, independente do nível de energia líquida das dietas.

ABSTRACT: The purpose of this study was to evaluate net energy and dietary ractopamine levels for barrows weighing 70 to 100kg. The 150 pigs investigated (initial weight 70.80±3.84kg) were distributed in a randomized block design with a 5×3 factorial arrangement, comprising five levels of net energy (2,300; 2,425; 2,550; 2,675; and 2,800Kcal kg-1 of diet) and three levels of ractopamine (5, 10, and 20ppm kg-1 of diet), with five replicates, and two animals per experimental unit. No interaction (P>0.05) was observed between net energy and ractopamine levels. Increasing the dietary net energy levels led to a linear reduction in feed intake, with a linear improvement in feed conversion. Net energy levels had no observable effect (P>0.05) on weight gain, final weight, or carcass characteristics. A dietary net energy level of 2,800Kcal kg-1 can be recommended for pigs weighing 70-100kg, improving feed conversion without affecting carcass characteristics, regardless of dietary ractopamine levels. Ractopamine levels above 5ppm did not affect performance or modify the quantitative characteristics of carcasses, regardless of dietary net energy levels.

ABSTRACT This study was carried out to evaluate the levels of digestible phosphorus in diets for barrows with a high potential for lean meat deposition from 50 to 80 kg. Eighty barrows, with an initial weight of 47.93±3.43 kg, were distributed in completely randomized blocks, with each group given five levels of digestible phosphorus (1.86, 2.23, 2.61, 2.99, and 3.36 g kg−1). There were eight replicates, and two animals per experimental unit. Phosphorus levels did not significantly influence feed intake, weight gain, or feed conversion ratio. Daily digestible phosphorus intake increased linearly as levels of phosphorus in the diet were increased. Phosphorus levels did not significantly influence muscle depth, loin eye area, backfat thickness, or the percentage and quantity of lean meat in the carcass. A linear increase was observed for feeding cost as the levels of digestible phosphorus in the diet were increased, and the level of 1.86 g kg−1 cost 29.4% less when compared with the level of 2.61 g kg−1. The dry matter, natural matter, the coefficient of the residue, and volatile solids of the waste were not significantly influenced by phosphorus levels. Conversely, it was possible to observe an increasing linear effect for total solids, total phosphorus, and total nitrogen in the waste of animals receiving diets with increased levels of digestible phosphorus. The level of 1.86 g kg−1, which corresponded to a daily intake of 4.77 g−1 of digestible phosphorus, meets the requirements of barrows weighing 50 to 80 kg.

O estudo foi conduzido com o objetivo de avaliar o desenvolvimento microbiológico em carne suína PSE em comparação à carne normal e o efeito da época do ano sobre a velocidade de proliferação dos mesmos. Amostras do músculo Longissimus dorsi de carcaças classificadas ao abate como PSE (pH45<5,8) e normais (pH45>5,8), foram coletadas após 24 horas de refrigeração, no momento da desossa, em um abatedouro comercial, com serviço de inspeção federal, situado na região da Grande Dourados (MS). As amostras (12 normais e 12 PSE) foram coletadas em duas épocas distintas do ano (outono e inverno) para as análises de coliformes totais, coliformes a 45ºC, mesófilos, psicotróficos, pseudômonas, bolores e leveduras aos 0, 5, 10 e 15 dias de armazenamento por refrigeração. O crescimento microbiano comportou-se de maneira semelhante entre os dois tipos de carne ao longo do período de armazenamento, exceto para a contagem de microorganismos aeróbios mesófilos totais, cujo desenvolvimento foi superior em carnes PSE até o 5º dia de armazenamento, igualando-se entre os dois tipos de carne posteriormente. Houve efeito da época do ano sobre a contagem de coliformes totais e a 45ºC, sendo sua velocidade de proliferação superior em carnes provenientes dos animais abatidos na época mais quente (outono).

The study was conducted to evaluate the microbiological development in PSE pork compared with normal meat and the effect of season of the year on the rate of proliferation of the same. Longissimus dorsi muscle samples from carcasses classified as PSE slaughter (pH45 <5.8) and normal (pH45 > 5.8) were collected after 24 hours of refrigeration, at the time of deboning, in a commercial slaughterhouse, with service federal inspection, located in the Grande Dourados region (MS). The samples (12 normal and 12 PSE) were collected at two different times of the year (fall and winter) for analysis of total and 45ºC coliforms, mesophylls, psychotropic, pseudomonas, yeasts and molds at 0, 5, 10 and 15 days of storage under refrigeration. Microbial growth behaved similarly between the two types of meat throughout the storage period, except for the count of mesophilic aerobic microorganisms, whose development was superior in PSE meat until the 5th day storage, matching between both types of meat later. Was no effect of season on the count of total coliforms and 45ºC, and their proliferation rate higher in meat from the slaughtered animals the warmer season (autumn).

Objetivou-se avaliar níveis de lisina digestível em dietas contendo 5 ppm de ractopamina sobre o desempenho e características quantitativas de carcaça de suínos em fase de terminação. Foram utilizados 96 suínos, sendo 48 machos castrados e 48 fêmeas, com peso inicial de 83,57 ± 4,07kg, distribuídos em delineamento inteiramente ao acaso, com quatro níveis de lisina digestível (0,94; 0,96; 1,02 e 1,04%), com três repetições de oito animais cada. O período experimental teve duração de 28 dias. O consumo de ração diário reduziu e a conversão alimentar melhorou linearmente de acordo com o aumento dos níveis de lisina digestível das dietas. Os pesos final, de frigorífico e de carcaça quente, o rendimento de carcaça, a quantidade de carne magra e o índice de bonificação aumentaram linearmente de acordo com o aumento dos níveis de lisina digestível. Não houve efeito dos níveis de lisina digestível sobre o ganho de peso diário, perda de peso durante o transporte e a porcentagem de carne magra da carcaça. Concluiu-se que, em dietas contendo 5ppm de ractopamina, o nível de 1,04% de lisina digestível melhora a conversão alimentar e aumenta o peso final, o peso e o rendimento de carcaça, a quantidade de carne magra e o índice de bonificação das carcaças dos suínos.

The objective was to evaluate levels of digestible lysine in diets with 5ppm of ractopamine on performance and carcass characteristics of finishing pigs. Ninety-six pigs, 48 barrows and gilts with initial body weight of 83.57 ± 4.07kg, were sorted in a complete randomized design with four levels of digestible lysine (0.94; 0.96; 1.02 e 1.04%), with three replications and eight animals each. The experimental period lasted 28 days. The feed intake was reduced and feed:gain ration improved linearly with increase digestible lysine levels in diets. Final, slaughter and hot carcass weights, carcass yield, amount of lean meat and payment index increase linearly with increase of digestible lysine levels. There was no effect of digestible lysine levels on daily gain, farm to slaughter shrink and lean meat percent. In conclusion, in diets with 5 ppm ractopamine, 1.04% digestible lysine improve feed:gain ration and increase final weight, carcass weight and yield, amount of lean meat and payment index of carcass of pigs.