Heinz body anaemia in lambs with deficiencies of copper or selenium

1. The progression of Heinz body anaemia was studied in groups of lambs of low- and high-copper status, produced through breeding or Cu supplementation, when they were transferred from improved pasture to rape (Brassica napus L.) in autumn. Some lambs had previously received selenium by injection. The Cu and Se supplements markedly increased superoxide dismutase (EC 1. 15. 1. 1; SOD) and glutathione peroxidase (EC 1. 11. 1. 9; GSHPx) activities respectively in the erythrocytes, and both supplements had elicited growth responses at pasture.2. At the time of transfer to rape, lambs not treated with Cu had lower whole-blood haemoglobin (Hb) concentrations and a higher percentage of erythrocytes containing Heinz bodies (6.6 v. 3.7%, P < 0.01) than Cu-treated lambs: the corresponding effects of Se treatment were similar in direction but lower in magnitude (P < 005).3. After grazing rape for 2 weeks the mean Hb concentration had fallen by 30 g/l while Heinz body count had increased from 5 to 25%. However, counts were negatively correlated with the initial values and were unaffected by the Cu and Se treatments which maintained high plasma Cu concentrations and SOD and GSHPx activities.4. The results provide the first evidence that Cu deficiency can induce Heinz body formation and the anaemia in grazing Cu-deficient lambs may be partly haemolytic in origin. The concomitant Se deficiency added marginally to the problem but neither the separate nor combined deficiencies increased the susceptibility of lambs to brassica anaemia

Níveis nutricionais de fósforo disponível para aves de corte ISA Label criadas em semiconfinamento

Foram realizados três ensaios para determinar os níveis nutricionais de fósforo disponível (Pd) para machos e fêmeas da linhagem ISA Label nas fases inicial (1 a 28 dias), crescimento (28 a 56 dias) e final (56 a 84 dias) criadas em semiconfinamento. Em cada ensaio, 480 aves com idade correspondente à fase de criação foram alojadas em 24 unidades experimentais contendo áreas de abrigo e de pastejo. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 4 × 2 (níveis de Pd e sexos) com três repetições de 20 aves. Os níveis de fósforo disponível avaliados foram: 0,25; 0,36; 0,47 e 0,58% na fase inicial; 0,18; 0,31; 0,44 e 0,57% na fase de crescimento; e 0,14; 0,27; 0,40 e 0,53% na fase final. Foram avaliados o ganho de peso, consumo de ração, consumo de Pd, conversão alimentar, teores de fósforo, cálcio e cinzas na tíbia e resistência à quebra óssea. De acordo com os resultados, o nível ótimo de Pd na ração na fase inicial, para machos e fêmeas são de 0,39 e 0,49%, que correspondem ao consumo de 3,94 e 3,96 g de Pd/ave, respectivamente. Para a fase de crescimento, recomenda-se 0,35% de Pd na ração para aves de ambos os sexos, que correspondem a consumo de 8,45 e 6,70 g de Pd/ave. Na fase final, recomendam-se os níveis de 0,32 e 0,30% de Pd, que correspondem a consumos de 12 e 9,5 g de Pd/ave para machos e fêmeas, respectivamente.It was performed three trials to determine the nutritional levels of available phosphorus (aP) for males and females of the strain ISA Label in the starter (1 to 28 days), growing (28 to 56 days) and finisher (56 to 84 days) phases, reared in a free-range system. In each trial, 480 birds with age corresponding to rearing phase were housed in 24 experimental units with shelter and pasture areas. It was used a complete random experimental design, in a 4 × 2 factorial scheme (levels of aP and sexes) with three replicates of 20 birds. The levels of aP evaluated were the following: 0.25, 0.36, 0.47 and 0.58% in the starter phase; 0.18, 0.31, 0.44 and 0.57% in the growing phase; and 0.14, 0.27, 0.40 and 0.53% in the finisher phase. Body weight gain, feed intake, aP intake, feed conversion, contents of phosphorus, calcium and ash in the tibia and bone breaking strength were evaluated. According to results, the optimum dietary aP levels in the starter phase, for males and females, are 0.39 and 0.49%, which correspond to the intake of 3.94 and 3.96 g of aP/bird, respectively. For the growing phase, it is recommended 0.35% of aP in the diet for birds of both sexes, which correspond to an intake of 8.45 and 6.70 g of aP/bird. In the finisher phase, it is recommended the levels 0.32 and 0.30% of aP, which corresponds to intakes of 12 g and 9.5 g aP/bird for males and females, respectively