Digestible methionine+cysteine in the diet of commercial layers and its influence on the performance, quality, and amino acid profile of eggs and economic evaluation.

This work aimed at evaluating the effects of 4 digestible Met+Cys levels on the diet of commercial layers and their influence on the productive performance, quality, and amino acid profile of eggs and economic viability of the activity. A total of 576 white Lohmann LSL-Lite layers was distributed into 6 replicates of 24 birds for each diet. The experimental design was completely randomized, with 4 treatments defined by levels evaluated in the feed (0.465, 0.540, 0.581, and 0.647%). The productive performance was measured for 30 weeks. The quality (34 and 50 wk old) and the amino acid profile of eggs (43 wk old) also were evaluated. A linear positive response was observed at higher Met+Cys levels for feed intake, number of eggs per housed bird, and digestible Met+Cys intake. Egg production, egg weight, egg mass, feed efficiency, and weight gain had their optimal values determined by the quadratic regression model at 0.638, 0.654, 0.647, 0.644, and 0.613% digestible Met+Cys, respectively. In the 34th wk, eggshell thickness decreased linearly at higher Met+Cys levels. In the 50th week, the optimal levels detected for eggshell thickness and percentage were 0.571 and 0.570% digestible Met+Cys, respectively. The percentages of proteins, branched-chain amino acids (leucine, isoleucine, and valine), histidine, and proline in eggs (albumen+yolk) showed a linear negative response in function of higher Met+Cys levels. Higher digestible Met+Cys levels (>0.630%) led to a good performance of layers, while lower Met+Cys levels improved the eggshell quality of layers in peak production. Optimal Met+Cys levels may change according to the price of the synthetic amino acid.

Efeitos da granulometria e da forma física da ração sobre o desempenho de frangos de corte / Effects of particle size and physical form of diets on broiler performance

Foram utilizados 936 pintos de corte machos e 1008 fêmeas da linhagem Cobb(r) criados no período de um a 45 dias. Os tratamentos foram compostos por duas formas físicas da ração (farelada e peletizada) e duas granulometrias do milho (3,8mm e 7,0mm). O delineamento experimental foi inteiramente ao acaso, em arranjo fatorial 2 x 2 (duas granulometrias x duas formas físicas), com seis repetições de 39 aves cada para os machos e seis repetições de 42 aves cada para as fêmeas. A ração peletizada produzida com moagem 3,8mm apresentou melhor PDI (P≤0,05). Aves fêmeas alimentadas com ração peletizada apresentaram maior consumo de ração, ganho de peso e melhor conversão alimentar que aquelas que receberam ração farelada. Não foi observada diferença significativa (P>0,05) entre os tratamentos para as variáveis ganho de peso, conversão alimentar e consumo de ração dos machos. Não houve influência da forma física e da granulometria sobre a viabilidade das aves em nenhuma fase de criação (P>0,05).

A total of 936 male chickens and 1008 female Cobb(r) were used from 1 to 45 days old. Treatments consisted of two physical forms (mash and pelleted diets) and two particle sizes ( corn ground through 3.8mm and 7.0mm sieves). The experimental design was completely randomized in a 2 x 2 factorial design (two particle sizes x two physical forms), with six replicates of 39 birds each for males and six replicates of 42 birds each for females. PDI from the pelleted physical form that was produced with 3.8mm grinding showed better results (P≤0.05). Female birds fed pelleted diets had greater feed intake, weight gain and better feed conversion than those fed mash diet. No significant difference (P>0.05) was observed between the treatments for male feed intake, weight gain and feed conversion from 1 to 45 days of age. There was no influence of the physical form and particle size on the feasibility of birds in any phase (P>0.05).

Efficiency of microbial phytase supplementation in diets formulated with different calcium:phosphorus ratios, supplied to broilers from 22 to 33 days old.

An experiment was conducted with broilers from 22 to 33 days of age to evaluate the efficiency of six microbial phytases supplemented in diets (1500 FTU/kg) that were formulated with three different calcium:available phosphorus (Ca:P(avail)) ratios (4.5:1.0, 6.0:1.0 and 7.5:1.0). A positive control diet without phytase was formulated with a Ca:P(avail) ratio of 7.5:3.4 to meet the nutritional requirements of the broilers. The P and ash contents of the tibia, magnesium in the plasma, performance, balance and retention of phytate phosphorus (P(phyt)), intake of total P and nitrogen (N), nitrogen-corrected apparent metabolizable energy and apparent digestibility of dry matter of the diets were not influenced (p > 0.05) by the type of phytase or the dietary Ca:P(avail) ratio. However, there was an interaction (p < 0.05) between the phytase type and the Ca:P(avail) ratio for the retention coefficients of total P, Ca and N. Phytase B resulted in the highest Ca deposition in the tibia (p < 0.01). Phytases D, E and F reduced the Ca concentrations in the tibia (p < 0.01) and plasma (p < 0.05). Phytase D increased the P level in the plasma and decreased the total P excretion (p < 0.01). Phytases E and F increased Ca excretion, while phytase A reduced it (p < 0.01). Regardless of the phytase type, increasing the dietary Ca:P(avail) ratio reduced (p < 0.05) the plasma P concentration and the excretion of total P and N and, conversely, increased (p < 0.05) the plasma concentration, intake and excretion of Ca. For the rearing period evaluated, it is possible to reduce the P(avail) of the diet to 1.0 g/kg when Ca is maintained at 7.5 g/kg, and the diet is supplemented with 1500 FTU of phytase A, C, D or E/kg. This diet allows the maintenance of performance and adequate bone mineralization, and it improves the Ca, total P and P(phyt) utilization in addition to reducing the excretion of N and P into the environment.

Content of plasmatic glycerol and activity of hepatic glycerol kinase in broiler chickens fed diets containing different sources and concentrations of glycerine.

The objective of this study was to evaluate the effect of three sources of glycerine (crude glycerine from soya bean oil - CGSO, mixed crude glycerine from frying oil and lard--MCG, and a semipurified glycerine from soya bean oil--SPGSO) in four concentrations in the diet (17.5, 35.0, 52.5 and 70.0 g of each type of glycerine per kg of feed) on the levels of plasmatic glycerol and the activity of the hepatic enzyme glycerol kinase in broilers of 22-35 days old (experiment I) and 33-42 days old (experiment II). The highest (p < 0.05) plasmatic glycerol level was detected in broilers fed diet containing CGSO. Independent of the source, increasing the concentration of glycerine led to a linear increase (p < 0.05) in the plasmatic glycerol concentration. In experiment I, all the diets containing glycerine resulted in increased concentrations of plasmatic glycerol, in relation to the control diet without glycerine. However, in experiment II, only the diet containing 17.5 g of CGSO per kg of feed and the diets formulated with any of the three types of glycerine in the inclusion concentrations of 35, 52.5 and 70 g/kg of feed resulted in higher plasmatic glycerol levels than those observed in the control broilers. The source of glycerine influenced the glycerol kinase activity only in experiment II, where the use of CGSO in the diet increased the enzyme activity. For both experiments, the glycerol kinase activity increased with the inclusion of glycerine in the diet. In conclusion, based on the absence of saturation of the glycerol kinase activity for the three glycerine sources and for both rearing periods evaluated, the broilers can metabolize the glycerol (at the level of the phosphorylation of the glycerol to glycerol-3-phosphate in the liver) present in the glycerine when the diet is supplemented with up to 70 g of glycerine per kg of feed.

Interleukin-10 and interferon-gamma patterns during tuberculosis treatment: possible association with recurrence.

Interleukin (IL) 10 and interferon-gamma (IFN-) levels in induced sputum supernatants of 21 tuberculosis (TB) patients at diagnosis and during chemotherapy were correlated to recurrence rates. IL-10 decreased until day 60 of treatment (T60), and between T60 and T180 it increased again in 7 cases (Pattern 1) and further decreased in 14 cases (Pattern 2). Follow-up of 69 months was performed in 20/21 cases; 6 had recurrence of TB, of which 5/7 (71%) had Pattern 1 and 1/13 (7.7%) Pattern 2 (OR 30.0, 95%CI 2.19411.3, P 0.0072). This was not observed for IFN-. High IL-10 levels at the end of treatment may function as a risk factor for TB recurrence.