Genetic variation of Lates calcarifer in Peninsular Malaysia based on the cytochrome b gene

A 312 bp segment of the mitochondrial cytochrome b gene was sequenced from 132 sea bass Lates calcarifer individuals from nine populations across Peninsular Malaysia. Phylogenetic analysis and analysis of molecular variance within and among populations showed no significant geographical structuring. Several populations formed discrete units while others were of mixed populations. The former group suggests a low gene flow among some populations while the latter suggests that widespread translocations have impacted the other wild and cultured local populations. The data from this study have important implications for fishery management, conservation of sea bass stocks and translocation policy for aquaculture and stock enhancement in Peninsular Malaysia.     

RAPD fingerprinting of the eel-loaches Pangio filinaris and Pangio piperata: preliminary evaluation

Random amplified polymorphic DNA (RAPD) analysis was applied to two morphologically similar species of the increasingly popular ornamental eel‐loaches, Pangio filinaris and P. piperata, collected from Kemat River, Terengganu and Padang Sanai River, Kedah, West Malaysia. Forty primers were tested in a preliminary screening. Of these, five (OPA‐03, OPA‐09, OPA‐11, OPA‐13 and OPA‐18) were chosen for their ability to provide consistent amplification. RAPD analysis differentiated the two species, with each showing different RAPD patterns for each primer used. The five primers generated a total of 82 scorable loci with up to 83% and 60% polymorphism in P. piperata and P. filinaris respectively. The RAPD banding patterns of these two species ranged from 2 to 14 fragments, with a size range of 250–2000 bp. Genetic similarity within species ranged from 0.610 to 0.985 (mean 0.799±0.14) for P. piperata and from 0.824 to 0.934 (mean 0.885±0.04) for P. filinaris respectively. The interspecies genetic similarity ranged from 0.386 to 0.486 with an average value of 0.434±0.040. Our study revealed RAPDs as useful genetic markers for the taxonomic clarification and assessment of genetic variability of the eel‐loaches.     

Radiographic assessment of pulmonary fluid clearance and lung aeration in newborn calves delivered by elective Caesarean section

The aim of this study was to develop a radiographic standard for the assessment of pulmonary fluid clearance and lung aeration in newborn calves. Caesarean‐delivered mature calves (n = 9) underwent lung assessment by thoracic radiography as well as arterial and venous blood gas analysis within the first 30 min, 1, 2, 3, 6, 12 and 24 hr after birth. The results indicated that newborn calves delivered by elective Caesarean section suffered from a physiological combined respiratory and metabolic acidosis with the dominance of respiratory acidosis, and an improvement in these conditions was recorded within 24 hr after birth. Concerning the radiographic results, clear lung fields, improvement in lung expansion, air content of the lung and absence of lung opacification occurred within 24 hr of birth. Furthermore, the ventral lung quadrant showed an improvement in radiographic opacification and lung expansion earlier than the dorsal lung regions. The findings of this study support the potential role of thoracic radiography in the assessment of pulmonary fluid clearance and lung aeration in newborn calves.     

Galactooligosaccharide and a combination of yeast and β-glucan supplements enhance growth and improve intestinal condition in striped catfish <Emphasis Type="Italic">Pangasianodon hypophthalmus</Emphasis> fed soybean meal diets

The effects of galactooligosaccharide (GOS) and a combination of yeast and β-glucan (YβG) supplementation of dietary soybean meal (SBM) on the growth and digestive performance of striped catfish Pangasianodon hypophthalmus were evaluated. Four isonitrogenous (30% protein) and isocaloric (19 MJ/kg diet) diets were formulated to contain 100% fish meal (FM) protein, 55% FM protein/45% SBM protein, FM-SBM supplemented with 1% GOS, and a combination of 1% yeast and 0.1% β-glucan, respectively. Each diet was fed for 12 weeks to three groups of 30 striped catfish fingerlings (average weight 16.45?±?0.07 g) maintained in circular fiberglass tanks (600 l). Growth, feed utilization, and muscle protein composition of fish improved significantly after supplementation with either GOS or YβG compared to the unsupplemented SBM diet, but were similar to those of fish fed the FM diet. Nutrient digestibility, digestive enzyme activities, villi and microvilli length were significantly increased in fish fed the supplemented SBM diets. The gut microbiota ranking profile showed that supplementing the SBM diet with YβG and GOS gave a ranking of Verrucomicrobia, Spirochaetes, Bacteriodetes, and Actinobacteria phyla similar to that of the FM diet. Thus, diet containing 45% protein from soybean supplemented with either GOS or YβG can be recommended to improve the growth and digestive performance of striped catfish.     

Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Hypertensive Effect of Protein Hydrolysate from Actinopyga lecanora (Sea Cucumber) in Rats

Food protein hydrolysates are known to exhibit angiotensin converting enzyme (ACE) inhibitory properties and can be used as a novel functional food for prevention of hypertension. This study evaluated the ACE inhibitory potentials of Actinopyga lecanora proteolysate (ALP) in vivo. The pre-fed rats with ALP at various doses (200, 400, 800 mg/kg body weight) exhibited a significant (p ≤ 0.05) suppression effect after inducing hypertension. To determine the optimum effective dose that will produce maximal reduction in blood pressure, ALP at three doses was fed to the rats after inducing hypertension. The results showed that the 800 mg/kg body weight dose significantly reduced blood pressure without noticeable negative physiological effect. In addition, there were no observable changes in the rats’ heart rate after oral administration of the ALP. It was concluded that Actinopyga lecanora proteolysate could potentially be used for the development of functional foods and nutraceuticals for prevention and treatment of hypertension.     

Genetic parameters for survival during the grow‐out period in the GIFT strain of Nile tilapia (Oreochromis niloticus) and correlated response to selection for harvest weight

The aims of this study were the estimation of genetic parameters for survival rate from tagging until harvest and the evaluation of the correlated response in survival rate to selection for harvest weight in the genetically improved farmed tilapia (GIFT) strain. The heritability for survival rate was low (0.038), and so was its genetic correlation with harvest weight (0.065), suggesting that selecting for the latter trait would have had no effect on survival. The calculation of the probability of survival by spawning season and line, fitting a model that included the random effects of individual animal and common environment, confirmed this prediction. There were very small and variable between line differences in the probability of survival, which generally favoured the selection line. We conclude that the focus of the GIFT programme on improving harvest weight was not detrimental to the survival of the fish during the grow‐out phase.     

Influence of arbuscular mycorrhiza and phosphate rock on uptake of major nutrients by Acacia mangium seedlings on degraded soil

To investigate the effects of arbuscular mycorrhiza (AM) and phosphorus (P) source on the uptake of major nutrients by Acacia mangium seedlings, three P sources were used: (1) Gafsa phosphate rock (GPR), (2) China phosphate rock (CPR), and (3) triple superphosphate (TSP). The plant samples were analyzed at 60, 75, 90, 105, 120, and 135 days after planting (DAP) for their N, P, K, Ca, and Mg contents. The uptake of these nutrients was significantly influenced by AM inoculation. Nutrient use efficiency in the AM-inoculated seedlings was also significantly higher than that in uninoculated seedlings. The effect of P sources on the uptake of these nutrients decreased in the order of TSP>GPR>CPR>control. There was a significant (P<0.05) interaction effect of AM and P source on P and K uptake by A. mangium. The uptake of P and K by mycorrhizal seedlings supplemented with TSP was significantly higher than that provided with other sources of P treatments. As a natural and cheaper P source, GPR might be used in combination with AM for growing A. mangium seedlings on degraded tin tailings.     

Effect of maturity on chlorophyll, tannin, color, and polyphenol oxidase (PPO) activity of sugarcane juice (Saccharum officinarum Var. Yellow Cane)

A study was conducted to determine the effect of sugarcane maturation on the contents of chlorophyll, tannin, and polyphenol oxidase (PPO) activity and on color change of sugarcane juice. The maturation period of the cane studied was between 3 and 10 months after planting. Different parts of the cane, namely, the top, middle, and bottom portions, were analyzed. Results obtained indicated that there were significant (P < 0.01) decreases in total chlorophyll a and b and tannin contents during maturity followed by slower rates of decrease of both parameters at the end of maturity stages. There were no significant differences (P > 0.05) in chlorophyll and tannin contents between the middle and bottom portions. On the other hand, the top portion of the stem had a significantly (P < 0.01) lower concentration of chlorophyll and a significantly (P < 0.01) higher content of tannin. PPO activity of sugarcane juice was determined using chlorogenic acid as a substrate. There was a highly significant difference (P < 0.01) in PPO activity of cane juice during maturity. PPO activity was high at the early development stage, decreased during maturation, and then remained relatively constant at the end of maturity. PPO activity was higher when chlorogenic acid was used as substrate. There were also significant differences (P < 0.01) in juice color (L*, a*, b* values) from different portions at different maturity stages. At the early stages, the color of extracted juice was dark, and then the juice turned to yellowish green during maturity. The decrease in green color or the increase in the yellow color could be associated with the decline in chlorophyll. The overall color change (DeltaE) at maturity indicated that the color of the middle and bottom portions was lower than that of the top portion.     

克伦特罗和生长激素对猪的生长及胴体组成的影响

将 36头试验猪分成 4组 :β 肾上腺素能激动剂处理组即克伦特罗处理组 (1kg饲料添加克伦特罗 3mg ,连续 2 8d)、生长激素处理组 (按 1kg体重每日注射 0 1mg生长激素 ,连续 2 1d)、克伦特罗和生长激素混合处理组及空白对照。试验结束后 ,测定猪的胴体组成 ,结果表明 :克伦特罗处理组和生长激素处理组的日增重分别比对照组提高 17%和 19% ,而混合处理组的日增重则下降 38% ,饲料摄入量下降 39% ;克伦特罗处理组背最长肌面积增加 19% ,背膘厚下降 2 3% ,与之相比 ,生长激素能加强猪的基础合成代谢 ,因而胴体成分没有明显改变 ;克伦特罗和生长激素混合处理组的活重减轻 ,胴体和内脏的比例下降 ,胴体明显瘦于对照组 ,但最长肌面积相等。结果还表明 β 肾上腺素能激动剂和生长激素对猪的饲料摄入量和胴体组成有互作效应 ,有关机理还需进一步研究。