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This study assessed the capacity of Jatropha curcas to physiologically adjust to salinity. Seedlings were exposed to increasing NaCl concentrations (25, 50, 75 and 100 m m) for 15 days. Treatment without NaCl was adopted as control. Shoot dry weight was strongly reduced by NaCl, reaching values of 35% to 65% with 25 to 100 m m NaCl. The shoot/root ratio was only affected with 100 m m NaCl. Relative water content ( RWC) increased only with 100 m m NaCl, while electrolyte leakage ( EL) was much enhanced with 50 m m NaCl. The Na+ transport rate to the shoot was more affected with 50 and 100 m m NaCl. In parallel, Cl− transport rate increased with 75 and 100 m m NaCl, while K+ transport rate fell from 50 m m to 100 m m NaCl. In roots, Na+ and Cl− transport rates fell slightly only in 50 m m (to Na+) and 50 and 100 m m (to Cl−) NaCl, while K+ transport rate fell significantly with increasing NaCl. In general, our data demonstrate that J. curcas seedlings present changes in key physiological processes that allow this species to adjust to salinity. These responses are related to accumulation of Na+ and Cl− in leaves and roots, K+/Na+ homeostasis, transport of K+ and selectivity (K-Na) in roots, and accumulation of organic solutes contributing to osmotic adjustment of the species. [ABSTRACT FROM AUTHOR]

The article discusses a study that evaluated the effect of genotype and sex on weight gain, livability and yields of six free-range broiler chicken genotypes. The feeding program for the chickens included diets based on corn and soybean meal. The effects of sex were observed in all ages of chickens regardless of weight gain, feed conversion and yields. Higher weight gain was observed in the genotypes Pesadão Vermelho, Carijó, Pescoço Pelado 3 and Pescoço Pelado 4.

Forage is a major constituent in most ruminant diets and exerts an economic impact on diet formulation due to the fact of contributing to reduce cost of available energy. Tropical forages are known for presenting both high concentration of fiber and to undergo the process of lignification at early stages of development. As a consequence it is observed a significant reduction on feed intake caused by variation on kinetics of degradation and passage in the rumen determining the available energy for microbial growth and efficiency, affecting the host performance. The present study evaluated the effect of increasing levels of dietary fiber from forage (fNDF) on lactating goats by using Tifton hay (Cynodon spp.) as the forage source, containing 78.54% NDF and 11.44% CP. Five goats were assigned to a 5x5 Latin square design using the levels of 19, 27, 35, 42 and 48 % of fNDF as the independent variables. Intake of dry matter (DM), of crude protein (CP), ether extract (EE), non-fiber carbohydrate (NFC), total digestible nutrients (TDN), and net energy of lactation (NEL) altered (p<.05) by increasing levels of ration fNDF. Intake of NDF did not differ among treatments as expressed as both kg/day or as a percentual of body weight, averaging 1.2% BW. Varying fNDF levels of diets did not influence apparent digestibility of DM, OM, NDF, CP and NFC (p>.05). A linear reduction was observed in milk yield as fiber level in ration was increased. Milk constituents did not alter by altering levels of fiber on ration. Similarly there was no influence of fDNF levels of diets on feeding behavior. The higher efficiency of using metabolizable energy consumed for milk yield was obtained by using 35% of fNDF. [ABSTRACT FROM AUTHOR]

Although the term quality is ambiguous when applied to the forage in ruminant nutrition it is highly correlated with intake and digestibility. Both chemical and physical changes occur in forage as a result of plant maturity affecting, as a consequence, the dynamics of digestion and passage of rumen digesta, resulting in filling effects, reduction of feed intake and decrease of milk production. The effect of the inclusion of neutral detergent fiber levels from forage (fNDF) with advanced maturity (86.24% NDF; 6.47% CP) was evaluated in goat diets. Feed intake, digestibility of dry matter and of nutrients, nitrogen balance, milk production, efficiency of use of metabolizable energy consumed (ME), and feeding behavior were used as dependent variables. Five dairy goats were assigned to a 5 x 5 Latin square design, using dietary fNDF levels of 20, 28, 35, 43 and 49% as independent variables. The intakes of dry matter (DMI), of nutrients, and of net energy (NEl) were reduced (p<.05) as fiber was added to ration. Conversely, intake of NDF increased (p<.01)suggesting ability for accommodation of fiber in the rumen despite the negative effect on intake. The fNDF level influenced (p<.05) the digestibility coefficients of dry matter, organic matter, crude protein and nonfibrous carbohydrates. Intake of nitrogen (g/day) was influenced in a quadratic manner with no effect on retained nitrogen. Quadratic effects were observed for the nitrogen excreted in the feces and urine, and a linear effect on nitrogen produced in the milk. No influence of fNDF levels was observed for milk constituents (fat, protein and lactose). A quadratic effect of fiber in diet was observed for milk yield with higher values obtained at 28% of fNDF. The levels of forage fiber studied did not influence values of efficiency of use of ME consumed for milk production. A variation on feeding behavior was noticed by increased time of rumination and mastication with a reduction on idle time as fiber from forage increase in diets. [ABSTRACT FROM AUTHOR]