Reproductive biology of the carp, Labeo bata (Ham.) from the River Kali,India

Spawning in Labeo bata occurs during July and August. Each individual spawns only once, with the onset of spawning directly dependent on the monsson season. Its success depends upon the access of gravid fish to a suitable spawning ground. The average fecundity is 192 785.     

Capture for culture: artificial shelters for grouper collection in SE Asia

This paper addresses a little‐discussed relationship between wild capture and mariculture, when the latter involves grow‐out of small wild‐caught fish or invertebrates in captivity. Seafood generated in this way is typically considered to be a form of aquaculture because it is assumed that, for animals removed from the wild when natural mortality is still very high, the protection conferred by culture operations will improve survivorship and enhance production. This assumption does not necessarily, however, apply when animals are removed well past the time of early high mortality. As one example of the implications of an early life‐history phase (ELP) fishery supplying culture operations, a preliminary study was conducted on an ELP fishery supplying live reef fish, especially groupers, in Southeast Asia. Grouper culture depends on both hatchery‐produced and wild‐caught fish which are then grown out to market size. Following interest to develop grow‐out operations in Indonesia, a pilot study was conducted to determine the sizes and capture rates of species of interest to the live fish trade, and to determine the likely environmental footprint of an artificial shelter (gango) type of capture method. From the results of the 15‐month study, we drew inferences regarding the sustainability of this fishing method and requirements of space, fish and materials for a viable grow‐out operation. The results showed that gangos were unselective for either species or size. Only 1.4% of the total fish catch (by number) were target species, mainly the grouper Epinephelus coioides, and most were large (mean total length was 13.6 cm) enough to have bypassed the early high mortality phase. Moreover, there were large non‐target catches that included many food fish species too small to be useful in catches. Given the large number and area of gangos needed for a viable operation, and that many groupers captured could probably have survived to reproduce, the ecological footprint of this approach could be substantial. These results, and literature on other ELP fisheries, suggest that these may often need management, have important links to other capture fishery sectors, and require careful evaluation of potential costs and benefits before introduction or development.     

Effects of increasing the stocking density of large carps by 20% on 'cash' carp–small fish polyculture of Bangladesh

This experiment was carried out in the framework of a project to develop a viable fish polyculture technology under Bangladeshi conditions that allows simultaneous fish production of small indigenous species for the farmers' family consumption and of large carp species as a cash crop. The objectives of this experiment were to assess the effects on fish performance and on the environment of adding 20% large fish to the basic ‘cash crop’ carp–small fish polyculture consisting of 10 000 fish ha^?1 of the large carp rohu Labeo rohita (Hamilton), catla Catla catla (Hamilton) and common carp Cyprinus carpio (L.) at a species ratio 1:1:1, and 15 000 fish ha^?1 of each small indigenous fish punti Puntius sophore (Hamilton) and mola Amblypharyngodon mola (Hamilton) (control). The treatment ponds were stocked with additional 2000 large fish ha^?1, either all rohu, or all catla, or all common carp, or half rohu and half common carp, or half catla and half common carp. The results obtained and the analysis of interactions through the food web that affect food resource availability of the different fish species and account for the trends and differences observed among treatments confirm the positive effect of common carp on rohu reported in previous experiments and show that a 20% increase in large carps stocking neither affect the survival of the large carps nor reduce harvesting biomass of the small fish for the farmer's family consumption. Increased stocking densities of each large carp species did not significantly reduce its own harvesting weight and mean growth rate, while significantly increased rohu and catla (but not common carp) harvesting biomass and yield. The complex relations between species led to inter‐ and intraspecific competition, which in some treatments increased growth or yield of one species and in other treatments of other species, so that the gains on one species and the losses on the other led to no significant total harvested biomass differences between treatments. Yet, the results herein reported may help farmers to select their species stocking ratios. Thus, if the main target of the farmer is rohu, then a stocking density increase of 10% common carp and 10% rohu would improve rohu growth rate (due to common carp) and result in 50% higher rohu harvesting biomass and yield. If the main target of the farmer is catla, then a 20% increase in catla stocking density would lead to 20% higher catla harvesting biomass.     

Effect of Substrate Dependent Ethylene on Cotton (Gossypium hirsutum L.) at Physiological and Molecular Levels Under Salinity Stress

The potential of encapsulated calcium carbide (ECC) in improving growth, yield and physiology of cotton under salinity was evaluated in pot experiment. Salinity was induced by sodium chloride (NaCl) at 0, 1250 and 2000 ppm. The ECC was applied at the rate of 0, 15, and 30 mg kg^?1 soil. The results revealed that ECC improved number of branches, yield, shoot dry biomass, root dry biomass, by 57, 67, 40, 22, and 18% respectively, over control. Similarly, net photosynthesis, stomatal conductance nitrogen, phosphorus and potassium (N, P and K) concentration of shoot were enhanced by 38, 34, 7, 25 and 11% over control, respectively. The induction of new set of proteins ranging from 11 to 26 kDa was also observed at various levels of ECC and salinity stress. These results proved the efficacy of very lower concentrations of ethylene produced by ECC and showed the behavior of different parameters of cotton to it under saline stress.     

Effect of Soil Type, Applications of Chicken Manure and Effective Microorganisms on Corn Yield and Microbial Properties of Acidic Wetland Soils in Indonesia

A field experiment was carried out to elucidate the effect of chicken manure (CM) and effective microorganisms (EM) on the yield of corn and chemical and microbial properties of acidic wetland soils. A split-split plot experimental design with three replications was used in this research. The main plot consisted of two types of soil. The sub-plot was for the application of CM, while the sub-sub plot was for the application of EM. Sweet corn seeds were planted and cultivated until harvest. Above ground plant biomass and round of the stem of an ear of corn were observed. Soil samples were taken and analyzed for chemical and microbial properties. The results showed that the interaction between soil types and CM application affected the corn yield, while EM had no effect. Similarly, the chemical and microbial characteristics of soils used were affected by soil type and the application of CM, while the effect of EM was not clear.     

Effect of weaning method on body weight,testicular growth,sexual behavior,age of puberty,and testosterone concentration of Beetal bucks

The current study evaluates the effects of early (8th week) and late (16th week of age) weaning of male goat kids on their body growth, testicular growth, sexual behavior, plasma testosterone concentration, and pubertal age. Early (n = 6) and late (n = 7) weaned Beetal bucks were weekly monitored from 18th to 38th week for their body weight, scrotal circumference, testicular volume, testicular echogenicity (via ultrasonography), sexual activities, and plasma testosterone concentration. In comparison to early-weaned, late-weaned bucks showed a marked increase (p < .05) in body weight (11.4 ± 0.8 vs. 13.7 ± 0.6kg), testicular volume (44.1 ± 7.2 vs. 79.8 ± 18.7cm³), scrotal circumference (10.7 ± 0.6 vs. 12.8 ± 0.7cm), and testicular echogenicity (28.3 ± 2.7 vs. 38.3 ± 2.1) from 18th, 28th, 21st, and 24th week onward, respectively. Sexual activities started earlier in late- than early-weaned bucks (22nd vs. 25th week, respectively). Moreover, the sexual behavior index was better (p < .05) after the 34th week in late than early-weaned bucks. The plasma concentration of testosterone (at 39 weeks of age) was relatively more and the onset of puberty was 2–3 weeks earlier (p < .05) in late than early-weaned bucks. In conclusion, age-based early weaning of male kids impairs their testicular growth, sexual behavior, and age at puberty compared to conventional weaning.     

Economic potential of rice precision farming in malaysia: the case study of Felcra Seberang Perak

Many attempts/efforts have been made to cope with the fluctuated production performance in rice production in Malaysia. There is a crucial need in technological advancement to tackle the issue of environmental variability, decreasing productivity and the rising cost in rice cultivation. The use of variable rate technology has increased rice yield through efficient resource allocation. Notwithstanding, an evaluation of the feasibility of this technology is required in terms of economic and intangible benefits. Therefore, this study attempted to determine the potential benefits that could come out of the use of precision agriculture technologies in rice cultivation. A precision farming technology package was developed by the Malaysian Agricultural Research and Development Institute. It consists of two components, namely a variable rate seed application system and a variable rate fertilizer application system. The study estimated the monetary benefits gained from the use of these two technology components at Federal Land Consolidation and Rehabilitation Authority Seberang Perak. The study also compared the performance of the technology package against the conventional practice. The Cost–Benefit Analysis exercise has been implemented to show the benefits and implications comprised in the study. It was found that there is an additional net income per hectare in between Malaysian Ringgit (MYR) 1109 to MYR 1333 due to the reduction in the production cost if the precision farming technology packages were adopted. The advancement in two cultivation stages showed a positive impact monetarily for both small-scale and large-scale farmers in the study. However, many challenges are to be faced for the technologies implementation since the existing rice cultivation recommended practices throughout all stages even yet to be practiced and taken seriously.

     

In vivo anthelmintic activity of Butea monosperma against Trichostrongylid nematodes in sheep

Seeds of Butea monosperma administered as crude powder (CP) at doses of 1, 2 and 3 g/kg to sheep naturally infected with mixed species of gastrointestinal nematodes exhibited a dose and a time-dependent anthelmintic effect. The maximum reduction of 78.4% in eggs per gram of feces (EPG) was recorded on day 10 after treatment with 3 g/kg. Levamisole (7.5 mg/kg), a standard anthelmintic agent, exhibited 99.1% reduction in EPG.