Feeding programs with reduced levels of available phosphorus and calcium on rations containing phytase for weanling piglets

Objetivando-se avaliar planos nutricionais comdiferntesníveis de cálcio (Ca) e fósforo disponível (Pd) em rações contendo fitase, 168 leitões, machos castrados e fêmeas, com peso corporal inicial de 8,11±0,61kg foramdesmamados aos 28 dias de idade e distribuídos em delineamento em blocos ao acaso, conforme o peso corporal, em sete tratamentos, com oito repetições e três animais por unidade experimental. Os tratamentos foram planos nutricionais (PN), sendo um controle sem fitase e os demais com níveis (%) decrescentes de Pd e Ca com 2.000 FTU de fitase, conforme segue: PN1: (Pd:0,435-0,385-0,315; Ca: 0,850-0,825-0,768); PN2: (Pd:0,370-0,320-0,250; Ca:0,850-0,825-0,768); PN3: (Pd: 0,305-0,255-0,185; Ca: 0,850-0,825-0,768); PN4: (Pd: 0,435-0,385-0,315; Ca:0,690-0,665-0,608); PN5: (Pd: 0,370-0,320-0,250; Ca:0,690-0,665-0,608); PN6: (Pd: 0,305-0,255-0,185; Ca: 0,690-0,665-0,608). O ganho de peso e o consumo de ração diários dos 28 aos 35 dias foram maiores para o PN3, PN5 e PN6 em comparação ao plano controle. Dos 28 aos 49 dias, o ganho de peso diário proporcionado pelo PN6 foi maior em comparação ao controle. O ganho de peso diário foi menor no PN6 em comparação ao PN1, dos 28 aos 63 dias. Os tratamentos PN1, PN2, PN4, PN5 proporcionaram maior mineralização óssea comparados ao controle. O PN1 resultou em maior mineralização óssea que o PN3, PN5 e PN6. OPN3 proporcionou menor mineralização óssea que os PN1, PN2 e PN4. O PN5 resultou em menor Ca ósseo comparado ao PN1. Com exceção do PN3, todos os tratamentos resultaram em P ósseo maior em relação ao controle, mas o PN3 resultou em P ósseo menor que o PN1. O PN4, PN5 e PN6 resultaram em menor relação cálcio:fósforo ósseo em relação ao controle. O P sérico foi menor no PN3 e PN6 em relação ao tratamento controle. Dentre os tratamentos contendo fitase, o PN3 resultou em menor P sérico que o PN1, PN4, e PN5; e o PN6 em menor P sérico que o PN5. Conclui-se que oPN6, correspondente a 0,305-0,255-0,185 de Pd, 0,690-0,665-0,608 de Cae2000 FTU/kgde fitase, apesar de proporcionar menor taxa de crescimento em relação ao PN5, resulta em desempenho satisfatório de leitões dos 28 aos 63 dias de idade.Aiming to evaluate feeding programs (FP) with different levels of calcium (Ca) and available phosphorus (aP) on rations containing phytase for piglets, one hundred sixty- eight barrows and females weighing 8.11 ± 0.61 kg were weaned at 28 days and blocked according to initial body weight. Inside each block, piglets were randomly distributed to one of seven feeding programs with eight replicates and three piglets per experimental unit.The treatments consisted of control FPwithout phytase and six with decreasing levels(%) of aP and calcium (Ca) with the addition ofphytase(2,000 FTU/kg), as follows: FP1: (aP: 0.435-0.385-0.315; Ca: 0.850-0.825-0.768); FP2: (aP: 0.370-0.320-0.250; Ca:0.850-0.825-0.768); FP3: (aP: 0.305-0.255-0.185; Ca: 0.850- 0.825-0.768); FP4: (aP: 0.435-0.385-0.315; Ca:0.690-0.665-0.608); FP5: (aP: 0.370- 0.320-0.250; Ca: 0.690-0.665-0.608); FP6: (aP: 0.305-0.255-0.185; Ca: 0.690-0.665- 0.608). The FP3, FP5 and FP6 resulted in higher average daily gain and feed intake in comparison to control,from 28 to 35 days. Only FP6 resulted in higher average daily gain in comparison to control, from 28 to 49 days. The FP6 resulted in lower verage daily gain when compared to FP1, from 28 to 63 days.The FP1, FP2, FP4 and FP5provided greater bone mineralization when compared to control. The FP1resulted in greater bone mineralization than FP3, FP5 and FP6. The FP3 resulted in less bone mineralization than FP1, FP2 and FP4. Bone Ca was lower on FP5 when compared to FP1. With the exception of the FP3, phosphorus (P) of the bone was higher on all treatments when compared to control, however, the FP3 treatment resulted in less bone P than FP1. The FP4, FP5 and FP6 resulted in lower bone Ca:P ratio when compared to control. The serum Pconcentrations were lower in FP3 and FP6 in comparison to control. Considering only treatments containing exogenousphytase, the FP3 resulted in lower serum P than FP1, FP4, FP5; and FP6 resulted in lower serum P in comparison to FP5 as well. In conclusion, the FP6 results in satisfactory performance of pigs from 28 to 63 days of agealthough providing lower growth rate when compared to FP5.Conselho Nacional de Desenvolvimento Científico e Tecnológic

Glutamine for broilers from 21 to 42 days maintained in thermoneutral environment

This study was conducted to evaluate the effects of dietary glutamine levels on performance and carcass traits of broilers kept in thermoneutral environment from 21 to 42 days of age. Hundred sixty eight male broilers Cobb® with 21 days of age and initial body weight of 900 ± 4.71 g were allotted in a completely randomized design with four levels of glutamine (0.00, 0.50, 1.00 and 1.50%), seven replicates with six birds each. Performance, relative weights of carcass, breast, thigh and drumstick and mRNA expression of HSP70 were evaluated. Birds were housed in environmental chambers with temperature of 23.2 ± 1.77ºC and relative humidity of 70 ± 5.82% corresponding to a calculated BGHI of 72 ± 2.75, which characterize thermoneutral environment. There was no effect of glutamine on feed intake, weight gain, and feed conversion of broilers. Glutamine had no influence on absolute and relative weights of carcass, breast, thigh, and drumstick of birds. There was not effect of dietary glutamine on mRNA expression of HSP70. Dietary glutamine did not affect performance and carcass traits of broilers from 21 to 42 days of age maintained in thermoneutral environment