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Scarcity of water and emission of greenhouse gases (GHGs) are the two key environmental issues affecting crop production in India.Reducing the carbon footprint (CF) and water footprint (WF) of crop production can help to mitigate the environmental hazards that stem from GHG emissions and water scarcity.The CFs and WFs of three major cereal crops,rice,wheat,and maize,were estimated for the year 2014 under the environmental conditions in India,based on national statistics and other data sources.To...  相似文献   
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1. The aim of this study was to determine the nitrogen balance and the performance of laying hens fed on diets with a protein content lower than the diets currently used in commercial practice but with adequate concentrations of lysine, sulphur amino acids, tryptophan and threonine. 2. Ninety-six Hy-Line Brown hens, 24 weeks old, were divided into 3 groups of 8 replicates and received, for 16 weeks, diets formulated to have 3 different protein concentrations: 170 (control), 150 and 130 g/kg CP and the same energy content. For each protein concentration, the contents of lysine, methionine, methionine+cystine, tryptophan and threonine were maintained at minimum requirement concentrations by supplying synthetic amino acids. 3. In the first half of the trial, egg production and egg weight were similar in all groups. From the 9th week onwards group 150 CP laid heavier eggs and had a slightly lower egg deposition and total mass. Food conversion ratio was best in the control group. 4. Nitrogen intake was related to the protein concentration of the diet, the food intake being almost the same in the 3 experimental groups. Faecal nitrogen content significantly and linearly decreased with reduction in dietary protein content and was about 50% of the intake. Considering the nitrogen faecal/intake ratio, the 150 CP group showed better nitrogen utilisation at each sampling time.  相似文献   
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1. The objective was to compare the effect of two litter types (wheat straw and wood shavings) and two different rearing conditions (Treated and Control) on welfare indicators, broiler performance, carcase injuries, particularly hock and foot pad dermatitis (FPD), litter characteristics and meat quality. 2. Treated conditions were characterised by a low stocking density (11 birds/m(2)), short photoperiod (16 h light: 8 h dark) and a large amount of litter (3 to 4.5 kg/m(2), respectively, for wheat straw or wood shavings). Control conditions were a high stocking density (14 birds/m(2)), long photoperiod (23 h light:1 h dark) and small amount of litter (2.3 to 3 kg/m(2), respectively, for wheat straw or wood shavings). In addition, the effects of two widely used litter materials, wheat straw and wood shavings, were investigated. 3. The combined effects of lower stocking density, greater amount of litter material and a photoperiod similar to the natural one, reduced the occurrence of FPD in Treated groups keeping the FPD score under the European threshold. 4. Improved rearing conditions led to faster growth rate associated with inferior feed efficiency, whereas litter type exerted negligible effects on broiler performance. 5. Litter moisture content, nitrogen and ammonia released by the litter were lower in Treated groups than Control groups. The use of wood shavings resulted in lower moisture and nitrogen concentrations in the litter.  相似文献   
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Adult Levant vole (Microtus guentheri) females, which at the age of 1 or 4 days had been in direct contact for 2 h with filter paper impregnated with a suspension of diethylstilbestrol dipropionate (DES) in soybean oil (0.125 mg DES/cm2), or whose nursing mothers had been in similar contact with DES during that period, were found to be sterile in the overwhelming majority of cases. Females slightly older (5–6 days old) at the time of such contact with DES (direct, or through their nursing mothers) retained their fertility.  相似文献   
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OBJECTIVE: To determine the relationship between 16 phenotypic parameters and the diameter of the tracheal lumen and endotracheal tube size (ETS) in Dalmatian puppies. STUDY DESIGN: A prospective nonblinded study. ANIMALS: Twenty-nine Dalmatian puppies, <5 months of age, referred to the Veterinary Faculty Clinics, Burdur, Turkey. MATERIALS AND METHODS: The diameter of the tracheal lumen was assessed using lateral cervical radiographs and the ETS was determined for each puppy. The relationships between ETS and body mass, age, dimensions of carpal and digital pads of the thoracic limb, length of the philtrum and the distance between the philtrum and lateral nasal edges were analysed statistically. RESULTS: The linear relationships between the ETS and the vertical length of the fourth digital pad (r2 = 0.915), and body mass (r2 = 0.908) were higher than with other parameters. Two predictive formulae for ETS derived from regression lines are: ETS +/- SE (0.20) = [body mass (kg) x 6/10]+2.5 and ETS +/- SE (0.19) = [vertical length of fourth digital pad (cm) x 6] - 2. CONCLUSIONS AND CLINICAL RELEVANCE: These formulae provide a practical guide to ETS selection in Dalmatian puppies.  相似文献   
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