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Nutrient Efficiency (nutrient + efficiency)

Distribution by Scientific Domains
Earth and Environmental Science100%

Selected Abstracts

Differences in Growth and Nutrient Efficiency Between and Within Two Channel Catfish Ictalurus punctatus Strains

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2005
Brian.
A 6-wk growth study was conducted comparing fingerling (mean weight = 24.7 g) USDA103 strain channel catfish Ictalurus punctatus to Norris strain channel catfish in an effort to determine strain differences in growth and nutrient efficiency. Variability within strains also was assessed by randomly selecting four families from each strain for comparison. On average, USDA103 fish gained significantly (P < 0.05) more weight (51.2 vs. 31.7 g) and length (4.7 vs. 4.1 cm) compared to Norris strain catfish. Significantly (P < 0.05) greater feed consumption (56.6 vs 41.3 g) and feed efficiency (95.7 vs. 89.9) for USDA103 catfish were also observed. Family differences in weight and length gain and feed intake were significant (P < 0.05) among USDA103 families; whereas, only differences in feed intake and feed efficiency were significant (P < 0.05) among Norris families. Nitrogen retention was higher (P < 0.05) for the Norris strain catfish (35.6%) relative to the USDA103 strain average (31.0%). The results of this study reiterate the superior growth and feed efficiency of the USDA103 strain of channel catfish. Observed differences among USDA103 families suggest that further improvements in weight gain can be made through selective breeding; however, improvements in feed and protein efficiency may be difficult. [source]

Soil exploration, nutrient partitioning, and nutrient efficiency of beech and spruce seedlings in a rhizotrone experiment

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 3 2003
Zhenyu Wang
[source]

Differences in Growth and Nutrient Efficiency Between and Within Two Channel Catfish Ictalurus punctatus Strains

JOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2005
Brian.
A 6-wk growth study was conducted comparing fingerling (mean weight = 24.7 g) USDA103 strain channel catfish Ictalurus punctatus to Norris strain channel catfish in an effort to determine strain differences in growth and nutrient efficiency. Variability within strains also was assessed by randomly selecting four families from each strain for comparison. On average, USDA103 fish gained significantly (P < 0.05) more weight (51.2 vs. 31.7 g) and length (4.7 vs. 4.1 cm) compared to Norris strain catfish. Significantly (P < 0.05) greater feed consumption (56.6 vs 41.3 g) and feed efficiency (95.7 vs. 89.9) for USDA103 catfish were also observed. Family differences in weight and length gain and feed intake were significant (P < 0.05) among USDA103 families; whereas, only differences in feed intake and feed efficiency were significant (P < 0.05) among Norris families. Nitrogen retention was higher (P < 0.05) for the Norris strain catfish (35.6%) relative to the USDA103 strain average (31.0%). The results of this study reiterate the superior growth and feed efficiency of the USDA103 strain of channel catfish. Observed differences among USDA103 families suggest that further improvements in weight gain can be made through selective breeding; however, improvements in feed and protein efficiency may be difficult. [source]

Blood and haemoglobin meal as protein sources in diets for gilthead sea bream (Sparus aurata): effects on growth, nutritive efficiency and fillet sensory differences

AQUACULTURE RESEARCH, Issue 10 2008
Silvia Martínez-Llorens
Abstract Two parallel experiments were conducted to evaluate the effect of partial substitution of fish meal by two different animal protein sources, blood meal (B) and haemoglobin meal (H) at 0, 50 and 100 g kg,1 of level inclusion in diets for gilthead sea bream, considering a long feeding period for juveniles (Trial 1) and a short feeding period (Trial 2) for on-growing fish. In Trial 1, 33 g juveniles were fed for 242 days and the fish fed with 5% and 10% of haemoglobin dietary inclusion obtained less growth, although feed efficiency, protein efficiency ratio and muscle composition were similar in all diets. In Trial 2, 179 g initial weight fish were fed for 164 days and growth of fish fed H10 showed the lowest growth, although nutrient efficiency and muscle composition were not affected significantly. The results of these experiments demonstrated that blood meal can substitute fish meal (up to 10%) with no effect on performance, but may lead to sensory differences compared with fish fed diet 0, while the inclusion of 5% blood meal had no effect on growth or sensory characteristics. Fish fed 10% haemoglobin inclusion had the poorest growth values. [source]