ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1988.tb00446.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractTwenty‐five domestic rice (Oryza sativaL.) cultivars were evaluated in a simulated rice/crawfish double cropping system in southwest Louisiana during 1983 and 1984. Wide variation was observed among cultivars in parameters believed to be important for maximizing productivity in such a system. Mean maturity ranged from 99 (Labelle) to 118 days (Starbonnet), while height ranged from 76 (Bellemont) to 130 cm (Della, Nato). Significant differences in grain yield response were observed, with yields ranging from 4,101 (Bluebelle) to 6,665 kg/hectare (Newbonnet). Straw dry matter production varied greatly, from 3,831 (Bellemont) to 9,170 kg/hectare (Della), and was positively correlated with plant height (r = 0.64;P =0.0001). Ratoon biomass production was negatively correlated with both grain yield (r = ‐0.39;P =0.0001) and maturity group (r = ‐0.69;P =0.0001). Plant senescence at grain maturity also varied greatly and appears to be a factor in post‐harvest ratoon capability. Early or very early maturing cultivars with both proven grain production and good ratooning capability appear best suited. Cultivar selection should be based upon individual farm situations and currently employed agronomic pr

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1988.tb00447.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY

摘要:

AbstractAn experimental feeding trial was conducted to study the feasibility of using soybean meal (SBM) to replace fish meal as a protein source for milkfish feeds containing 30% and 40% dietary protein. The replacement levels were 0%, 33%, 67% and 100%. In each replacement level, methionine was supplemented to the amount that the fish meal control group contained. The experiment was conducted for eight weeks in aquaria that were part of a closed recirculated filtered rearing system. At both dietary protein levels, fish in the 100% replacement groups had significantly (P<0.05) lower weight gain, feed conversion rate and protein efficiency ratio than that of the groups fed the control diets containing only fish meal. Growth in the 67% and 33% replacement groups did not differ significantly from that of the control groups. The apparent protein digestibility, dry matter digestibility and body composition of fish were similar in all the dietary groups. These data suggest that up to 67% of fish meal in milkfish feed could be replaced by commercial hexane‐extracted soybean meal and a methionine supplement without any adverse effect on milkfish growth and feed conversion rat

ISSN:0893-8849    

DOI:10.1111/j.1749-7345.1988.tb00448.x

出版商:Blackwell Publishing Ltd    

年代:1988

数据来源: WILEY