Abstract Employing experimental-ecological methods, the feeding and vitality of adult Anthocidaris crassispina were investigated. The results showed that A. cras- sispina exhibited an obvious preference on five differ...Abstract Employing experimental-ecological methods, the feeding and vitality of adult Anthocidaris crassispina were investigated. The results showed that A. cras- sispina exhibited an obvious preference on five different seaweeds, with the preference order of Betaphycus gelatinum 〉 Sargassum hemiphyllum 〉 Gelidium amansii 〉 Ulva lactuca 〉 Codium fragile. The daily feed intake of A. crassispina differed among U. lactuca, S. hemiphyllum and B. gelatinum. The feeding was affected by water temperature, seaweed species and body weight. The optimal vitality and feed intake were observed under 23 -27℃, which were inhibited under whether too higher or too lower temperature. Under the optimal temperature for feeding, the daily feed intake of adult A. crassispina assumed an exponentially-decreasing trend with increase of body weight.展开更多
Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initia...Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initial body weight as the blocking factor. There were 3 treatments corresponding to 3 dietary levels of benzoic acid: 0, 0.3%, and 0.5%. In experiment 1, a total of 144 PIC L1050 barrows(initial body weight 7.1 ± 0.6 kg) were used with each treatment replicated 8 times. In experiment 2, a total of 288 PIC L1050 barrows(initial body weight 36.1 ± 3.6 kg) were used with each treatment replicated 16 times.There were 6 barrows in each replicate pen for both experiments. Experiments 1 and 2 lasted 28 and 70 days, respectively. In experiment 1, average daily gain(ADG) of all growth phases increased linearly(P < 0.05) with increasing supplementation of benzoic acid, which led to a linear improvement in average body weight on d 28(P < 0.05). There was also an improvement in feed conversion ratio(FCR) of d 0 to 14(linear effect: P < 0.05) and in average daily feed intake(ADFI) of d 14 to 28 and d 0 to 28(linear effect:P < 0.01). In experiment 2, ADG during d 0 to 35 and d 35 to 70 and average body weight on d 35 improved linearly(P < 0.05) with increasing supplementation of benzoic acid. Average daily gain of d 0 to70 and average body weight on d 70 increased significantly in a both linear and quadratic manner. There was a linear improvement in FCR in all growth phases(P < 0.05). In conclusion, the dietary inclusion of benzoic acid at the supplementation levels of 0.3% and 0.5% significantly improved the growth performance of nursery and grower-finisher pigs in the current study; the nursery pigs responded to the dietary supplementation of benzoic acid up to 0.5% linearly while the grower-finisher pigs achieved the optimal ADG at the calculated supplementation level of 0.36%.展开更多
基金Supported by National Key Technology R&D Program of China(2012BAD-18B02,2012BAD18B01-2)Public Science and Technology Research Funds Projects of Ocean(201205021-3)Special Scientific Research Funds for Central Non-profit Institutes(South China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences)(2014TS07,2015TS05)
文摘Abstract Employing experimental-ecological methods, the feeding and vitality of adult Anthocidaris crassispina were investigated. The results showed that A. cras- sispina exhibited an obvious preference on five different seaweeds, with the preference order of Betaphycus gelatinum 〉 Sargassum hemiphyllum 〉 Gelidium amansii 〉 Ulva lactuca 〉 Codium fragile. The daily feed intake of A. crassispina differed among U. lactuca, S. hemiphyllum and B. gelatinum. The feeding was affected by water temperature, seaweed species and body weight. The optimal vitality and feed intake were observed under 23 -27℃, which were inhibited under whether too higher or too lower temperature. Under the optimal temperature for feeding, the daily feed intake of adult A. crassispina assumed an exponentially-decreasing trend with increase of body weight.
文摘Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initial body weight as the blocking factor. There were 3 treatments corresponding to 3 dietary levels of benzoic acid: 0, 0.3%, and 0.5%. In experiment 1, a total of 144 PIC L1050 barrows(initial body weight 7.1 ± 0.6 kg) were used with each treatment replicated 8 times. In experiment 2, a total of 288 PIC L1050 barrows(initial body weight 36.1 ± 3.6 kg) were used with each treatment replicated 16 times.There were 6 barrows in each replicate pen for both experiments. Experiments 1 and 2 lasted 28 and 70 days, respectively. In experiment 1, average daily gain(ADG) of all growth phases increased linearly(P < 0.05) with increasing supplementation of benzoic acid, which led to a linear improvement in average body weight on d 28(P < 0.05). There was also an improvement in feed conversion ratio(FCR) of d 0 to 14(linear effect: P < 0.05) and in average daily feed intake(ADFI) of d 14 to 28 and d 0 to 28(linear effect:P < 0.01). In experiment 2, ADG during d 0 to 35 and d 35 to 70 and average body weight on d 35 improved linearly(P < 0.05) with increasing supplementation of benzoic acid. Average daily gain of d 0 to70 and average body weight on d 70 increased significantly in a both linear and quadratic manner. There was a linear improvement in FCR in all growth phases(P < 0.05). In conclusion, the dietary inclusion of benzoic acid at the supplementation levels of 0.3% and 0.5% significantly improved the growth performance of nursery and grower-finisher pigs in the current study; the nursery pigs responded to the dietary supplementation of benzoic acid up to 0.5% linearly while the grower-finisher pigs achieved the optimal ADG at the calculated supplementation level of 0.36%.