Straw preservation reduced total N2O emissions from a sugarcane field

Post‐harvest biomass can be used as feedstock for energy production and alter N₂O emissions from the soil, which is among the main issues determining bioethanol sustainability. To assess the effects of sugarcane straw return on gas emissions, we established a field experiment in which 0, 50, 75 or 100% (0, 5.65, 8.47 and 11.30 Mg/ha dry biomass, respectively) of the crop residues (straw) was left in the field during the first two ratoon crops. As fertilizer is applied in bands to sugarcane, we also investigated the contribution of different positions to the N₂O emissions within the field. There was an interactive effect between straw and inorganic fertilizer, leading to a nonlinear effect of crop residues on the fertilizer emission factor (EF). However, straw consistently reduced N₂O emissions from the field, acting mainly in the unfertilized areas in the field (P < 0.05). We observed that considering the typical EF used in the literature, the N₂O‐N emissions attributed to fertilizer ranged from 0.19 to 0.79 kg/ha, while the total emissions ranged from 3.3 to 5.2 kg/ha, from the highest amount of straw to the lowest. We conclude that overall, the fertilizer EF is not as relevant as the total emissions, based on this and other studies. Consequently, management practices might be more effective in improving the GHG balance than changing inorganic fertilizer use. We conclude that keeping up to 11 Mg/ha of straw with a large C:N ratio (>100:1) on site might increase sugarcane production sustainability by reducing the greenhouse gas emissions from the field.     

Physicochemical parameters,fatty acid profile,and sensory attributes of meat from lambs fed with cassava dregs in replacement of corn

Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on...     

Organic trace minerals on productive performance,egg quality and immune response in Bovans White laying hens

This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo‐Amino‐Phosphate‐Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty‐week‐old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals.     

Ruminal and morphometric parameters of the rumen and intestines of sheep fed with increasing levels of spineless cactus (Nopalea cochenillifera Salm-Dyck)

Tropical Animal Health and Production - The objective of this study was to evaluate the ruminal parameters (pH, N-NH3, and microbial protein) and morphometry of the rumen and intestine of sheep fed...     

Carcass characteristics and meat quality of sheep fed alfalfa hay to replace Bermuda grass hay

Tropical Animal Health and Production - The objective of this study was to evaluate carcass characteristics, meat quality, and organ and viscera weight of forty male sheep, not castrated, initially...     

Effect of colostrum treated by heat on immunological parameters in newborn lambs

Seventeen newborn lambs were fed with untreated colostrum (group A) and 18 lambs were fed with colostrum treated by heat (56 °C, 30 min) (group B). Blood samples were obtained at seven time points from day 0 to 38 of life. Clinical status and body weight were recorded and serum protein fractions and IgG levels were determined in blood. Phagocytosis of neutrophils from the lambs and opsonic capacity of their serum were examined using a flow cytometry method. As an indicator of in vivo cellular immunity, reactions to intradermal injection of phytohemagglutinin (PHA) were examined at 8 and 16 days of age. There were no clinical signs of disease and no significant differences in body weight between groups. Lambs from group B had lower total protein initially and lower γ-globulin and IgG levels until day 32 compared to lambs from group A (P < 0.01). Heat treatment of colostrum had no significant effect on serum opsonic capacity or phagocytosis by neutrophils and these functions increased with age. However, responses to PHA in lambs from group B were lower (P < 0.01) than group A at day 8 of life, but not at day 16, suggesting that cellular immunity was affected by the treatment of colostrum. These results showed that colostrum treated by heat impaired cellular and IgG levels in lambs, but not phagocytic function. However, these changes did not affect the health or performance of the lambs.     

Exogenous paraoxonase‐1 during oocyte maturation improves bovine embryo development in vitro

Paraoxonase‐1 (PON1) is an enzyme found in serum and follicular fluid that protects cell membrane and circulating lipids against oxidative damage. The aims of this study were to measure the direct effects of recombinant PON1 (rPON1) on bovine oocyte maturation at the molecular level (gene expression) and to measure the carry‐over effects of PON1 on pre‐implantation embryo development in vitro. COCs were submitted to IVM with the addition of 0.0, 0.02, 0.04 and 0.08 mg ml^?1 of rPON1, corresponding to an average PON1 arylesterase enzyme activity of 2.2 ± 0.4, 15.5 ± 1.5, 30.2 ± 3.0 and 57.9 ± 5.0 U ml^?1, respectively. The results indicated that addition of rPON1 during IVM improved embryo development in a dose‐dependent manner as D7 embryo development was 22.2%, 29.4%, 32.2% and 37.0% for the treatment groups, respectively (p = 0.02). In conclusion, addition of PON1 enzyme during IVM exerted dose‐related positive effects on embryo development rates to blastocysts.