Effect of Stocking Density and Rearing Facility on Growth and Profitability of Tilapia rendalli Fry
A study was conducted to compare the growth potential of Tilapia rendalli at three different stocking densities, using different rearing facilities. T. rendalli fry of 0.9±0.1g average weight were stocked in tanks and hapa-in-ponds at the stocking density of 30, 60 and 90 fry/m 3 . Locally made feed (CP-18%) was administered at 5% body weight three times a day for three months. Monthly sampling was conducted to assess growth by measuring weight and length for specific growth rate (SGR), average daily gain (ADG), weight gain (WG), and biomass (BM). The results of the study showed a significantly higher (P 0.05) as well as within the stocking densities (P > 0.05). The results of this study have a significant contribution towards stocking densities as well as rearing facilities used by hatchery operators. It is recommended that hapas mounted in pond fry rearing for T. rendalli fingerling production is most ideal. The results of the present study suggested that production of good quality fingerlings at stocking densities of 30 fry/m 3 must be adopted in the culture of T. rendalli as fish grows faster than the other stocking densities of 60 and 90 fry/m 3 as demonstrated in this study.
Comparative growth performance of mixed-sex and monosex Nile tilapia population in freshwater cage culture system under Indian perspective.
Cage culture is one of the important methods for intensive culture of tilapia in large water impoundments. But, information related to growth performance of androgen-treated monosex tilapia population during cage culture under the ecological conditions of India is limited. The aim of this study was to compare the growth potential of control, mixed-sex and androgen-treated, monosex tilapia in confined environment of cages. Control and hormone treated fish were stocked separately in mesh cages at a density of 50 fry / m3 and it was found that the androgen treated monosex fish grew significantly larger than their control mixed-sex counterparts. The monosex population showed a significantly higher weight, length, depth, specific growth rate, daily weight gain, protein efficiency ratio and body protein content than the mixed-sex tilapia population. Thus, culture of hormone treated monosex tilapia in cages can be considered ideal for augmented production of the fish under Indian context.
Inferring Learning Strategies from Students ’ Errors
Student models in an Intelligent Tutoring System (ITS) aim at representing both correct and incorrect knowledge of the student in a particular domain of learning. This data serves as the basis upon which the Tutor can dispense remedial feedback. This paper presents a framework in which learners’ errors are diagnosed, classified and linked to cognitive processes associated with learning. The cognitive processes we identify are those of generalization, misattribution and ignorance. Our system applies to the domain of Second Language Acquisition and our approach uses Chomsky’s linguistic theory of Principles and Parameters. We particularly concentrate on the acquisition of the Phrase Structure component.