The Effect of Immersion Duration in Thyroxine Hormone on Growth of Snakehead Fish Larvae (Channa striata)

The aim of this research was to determine the best immertion duration to increase growth rate of snakehead fish larva. The research was conducted in Fish Breeding unit Batanghari Sembilan Indralaya, Kabupaten Ogan Ilir. This research used a Completely Randomized Design (CRD), with five treatments (0, 12, 24, 36, and 48 hours of immertion), with three replications. The parameters observed were growth, survival rate and water quality. The results of this research show that the highest growth rate found in the 24 hours of treatment with the average value of 0.17 g of weight and increase in length of 1.90 cm. The best survival contained in treatment of immersion for 36 hours with the average value of 71.67%.

In vitro culture as an aid to conservation of indigenous ferns: Diplazium proliferum

With the ever growing population and economic needs of Mauritius, the flora of Mauritius has never been in more danger and one group of vascular plants is even more in peril; ferns.<em> Diplazium proliferum</em> is indigenous to the Mascarene region and is considered as a rare species in Mauritius. The need to develop a tested <em>in vitro</em> propagation protocol is a must to protect the biodiversity of Mauritius. This experiment was geared towards the establishment of a proper sterilization technique and the effect of 6-benzylaminopurine (BAP) and light on <em>in vitro</em> culture of this fern. Sterilization with 0.05% Mercuric chloride was effective to eliminate fungal contamination and allow germination of spores. Culture media supplemented with BAP did not significantly increase growth rate of both gametophytes and sporophytes of<em> D. proliferum</em>. Present results suggest efficient sterilization methods to be a crucial stage for successful<em> in vitro r</em>egeneration of ferns. The established protocol will be used as an optimized baseline protocol for the propagation of other indigenous ferns.

Dietary zinc oxide supplementation in weaner piglets does not cause differential expression of digestive enzymes

Piglet weaner diets are often supplemented with the antimicrobial mineral zinc oxide (ZnO) to minimise the characteristic growth check post weaning in commercial systems. Zinc has been shown to decrease the incidence of scours, maintain gut morphology and feed intake, and increase growth rate, although the mechanism for these effects remains unclear. Weaning is often accompanied with a decrease in digestive enzyme production by enterocytes, decreasing digestive and absorptive capacity. Digestive enzyme requirements also alter with the dietary change from milk to a solid cereal-based diet, and improvements in enzymatic adaptations may increase digestion and absorption and improve feed utilisation. It is hypothesised in this study that the growth effects of ZnO are linked to improvement in digestion by altering digestive enzyme expression and activity. The aim of this study was to investigate whether the effects of ZnO are linked to expression of the digestive enzymes lactase phlorizin hydrolase (LPH) and aminopeptidase N (ANPEP) in the small intestine (S.I.).

Surface Morphologies and Optical Properties of Homoepitaxial ZnO Grown by Close-Spaced Chemical Vapor Transport

Chemical vapor transport (CVT) using carbon as a transporting agent is studied for homoepitaxial growth on O-polar ZnO substrates. To increase growth rate at high temperatures, we keep a substrate close to ZnO source powder. Surface smoothness and crystal quality of epilayers are remarkably improved by increasing a substrate temperature. Smooth surfaces are observed on the epilayer grown at substrate temperatures above 920°C.

Insulin-like growth factor-I and analogues increase growth in artificially-reared neonatal pigs

Exogenous insulin-like growth factor (IGF)-I has been shown to increase growth rate in neonatal pigs while an analogue of IGF-I, long arginine (LR3) IGF-I, has been shown to be more potent than IGF-I in the rat. Therefore, two studies were conducted to determine whether IGF-I and LR3IGF-I increase growth in the artificially-reared neonatal pig. Expt 1 involved forty-two (2 kg initial weight) pigs infused with either control, IGF-I (2, 4 or 8 μg/h) or LR3IGF-I (2, 4 or 8 μg/h) infusions for 8 d. Pigs were weighed and then offered 1·7 MJ (gross energy) milk replacer/kg0·75 per d. Expt 2 involved eighteen pigs (2 kg initial weight) treated with control saline, IGF-I (8 μg/h) or LR3IGF-I (8 μg/h) infusions. After 9 d an additional pump was inserted to increase the infusion rates of each of the growth factors (16 μg/h) for a further 9 d. Cows' milk was provided ad libitum. In Expt 1 there was no overall effect of growth factors on daily weight gain or slaughter weight. However, milk intake was greater in pigs infused with growth factors (909 v. 867 g/d, P=0·027), with an apparently greater milk intake by the pigs infused with IGF-I compared with LR3IGF-I (920 v. 898 g/d, P=0·12). Infusion of LR3IGF-I decreased plasma IGF-I concentrations, but had no effect on plasma IGF-II concentrations. In Expt 2, neither IGF-I nor LR3IGF-I infusion had any effect upon daily weight gain over the first 9 d of the study. However, over the second 9 d of the study, daily weight gain was increased in LR3IGF-I-infused pigs (457 v. 386 g/d, P<0·01), but not in pigs infused with IGF-I (413 v. 386 g/d, P=0·15). Milk intake was not different during the first 9 d of the study but was significantly greater in pigs infused with growth factors over the second half of the study (3407 v. 2905 g/d, P<0·01). Plasma IGF-binding protein-3 concentrations were highly correlated (R=0·85) with average daily gain over the 3 d preceding blood sampling. In conclusion, exogenous IGF-I and particularly LR3IGF-I can increase growth rate and milk intake in artificially-reared pigs fed ad libitum but not in limit-fed piglets.

The effects of sequence of feed allocation within the day on the growth and carcass characteristics of lambs fed barley based diets

Feeding lambs diets formulated to be synchronous for their hourly release of energy and nitrogen (N) in the rumen has been shown to increase growth rate and feed conversion efficiency (Witt et al. 1997). However the diets used contained different feed ingredients and therefore the differences in performance may have been due to some aspect of the diet that was not characterised. The objectives of the current experiment were to supply the same quantity of feed ingredients over a 24h period but alter the sequence of allocation within the day to achieve different patterns of energy and N release in the rumen and investigate the effects on growth and metabolism of ram lambs when fed at a restricted level.