Fish are fascinating creatures with a certain degree of immunity comparable to those of mammals. The fish's immune system consists of two major components, innate and adaptive immunities. Innate immunity is non-specific and acts as the primary line of protection against pathogen invasion while adaptive immunity is more specific to a certain pathogen/following adaptation. Innate immunity consists of the non-specific cellular and the non-specific humoral components. The non-specific cellular component consists of toll-like receptors (TLRs), macrophages, neutrophils, eosinophils and non-specific cytotoxic cell while the non-specific humoral component involves lysozyme, the complement, interferons, C-reactive proteins, transferrins and lectins. They work together at the initial stage to prevent pathogen invasion. On the other hand, the adaptive immune system consists of highly specilised systemic cells and processes that are separated into two main components: the humoral and cellular components. Three types of antibodies, the IgM, IgD and IgT, are the major constituents of the humoral immunity, which act on invaded extracellular pathogens. The cytotoxic T-lymphocyte cells are the major component of the cellular immunity that frequently kills virus-infected and intracellular bacterial or parasitic-infected cells. Both innate and adaptive immunities complement each other in the host's attempt to prevent infection.
A review of literature showed that numerous intensive surveys have been carried out on the ichthyofauna of the peat swamp forests (PSFs) of Malaysia. This review aims to provide a checklist of blackwater fish species in Malaysia from available published literature, and address their economical importance, conservation status and problems of PSFs. A total of 198 peat swamp fish species from 32 families have been recorded in Malaysia. From this number, a total of 114 species from 23 families, representing about 40% of the known fish fauna in Peninsular Malaysia, were recorded from north Selangor PSF. Meanwhile, a total of 49 species belonging to 18 families, 13 species from seven families, 58 species belonging to 19 families, and nine species from five families were recorded from the peat swamps of Perak, Johor, Pahang and East Peninsular Malaysia (parts of Pahang and Terengganu), respectively. Meanwhile, 31 species from 12 families and 40 species belonging to 13 families were recorded from Sabah and Sarawak, respectively. Family Cyprinidae has the highest recorded species, followed by Osphronemidae, Bagridae and Siluridae. The IUCN Red List revealed 12 threatened species facing risk of extinction. The importance of conserving PSFs was outlined and suggestions made in line with the objectives of conservation. Findings from literature revealed that Malaysia's PSFs are rich in fish diversity, contrary to previous belief, and should therefore be conserved and protected to ensure the richness of their fish diversity.
Ichthyofauna, peat swamp forest, conservation, Malaysia
Climate change acts as a major threat to climate sensitive sectors such as agriculture and animal husbandry. This change in climate will be a greatest challenge to about 1.3 billion population who depends on animal husbandry as their livelihood. Heat stress is considered as one of the primary factors that imposes negative impacts on production and reproduction in farm animals. In addition, it also alters the immune functions of the animal and makes them susceptible to infectious diseases. Based on the duration of exposure, heat stress either enhances or suppresses the immune functions in farm animals. The stress signal acts mainly through hypothalamo-pituitary-adrenal (HPA) axis to modulate the immune response. Generally, it is considered that heat stress acts to shift the adaptive immune function from cell mediated to humoral immunity and thus weakens the animal immune function. Another aspect of this climatic change is the threat of emerging and re-emerging pathogens and disease vectors for which livestock needs fine-tuned immune system to fight against naïve pathogens. Thus, the heat stress-immune system interactions need to be studied thoroughly in order to introduce various management and nutritional strategies to alleviate the ill-effects of heat stress in farm animals.
Stability of grain yield in upland rice due to the unpredictability of environmental indices is of important consideration in the development of cultivars adapted to fairly wide cultivation zone. A study was conducted with fifteen upland rice varieties in two locations in South-Western Nigeria to evaluate the contribution of panicle and grain characters to stable grain production. Data collection spanned five environments and was subjected to stability analyses. The effects of genotype, environment and their interaction were significant for all the panicle and grain characters. Broad sense heritability estimate (HB) was moderate for hundred grain weight (62.4) and grain length (58.9) but was generally low for other grain yield traits, particularly grain weight per panicle (11.6) and grain weight per plant (5.6), respectively. Stability variance identified different genotypes as stable for most of the characters. The crossover attribute of AMMI PC 1 however complimented the significant verdict returned by the stability variance though the former also specified the direction of instability. The Yield Stability index (YSi) harnessed the advantages of the two statistics to identify different genotypes as stable for different characters. Thus, there is a need to constitute a pool of genotypes for the evolution of superior synthetic but stable cultivars.
This study evaluates the growth of five species of marine microalgae; Chaetoceros muelleri, Isochrysis galbana, Pavlova lutheri, Nitzschia acicularis and Navicula sp., isolated from coastal waters of Kudat in Sabah, Malaysia, using different cultivation techniques for mass outdoor culture. The microalgae were locally isolated and identified based on their morphology. The growth of the microalgae was compared between carboy and polythene bag culture. Results showed that cell count for all species was significantly higher in the polythene bag culture compared to carboy culture (p < 0.05). The time to harvest was also shorter (2-3 days) compared to carboy culture. In particular, Chaetoceros muelleri produced the highest cell count of 87 X 106 cells/ml and shortest time of 2 - 3 days to harvest. There were significant differences (p < 0.05) in cell count between indoor and outdoor mass culture, and these suggest the feasibility to culture the microalgae outdoor, reduce hatchery operation cost and save time.
Research on production and the use of cellulase and xylanase by commercial microbial strains is widely reported. However, research on production of cellulase and xylanase by local isolates of Trichoderma harzianum known as potential cellulase producers is still very limited. T. harzianum SNRS3 was used for cellulase and xylanase production from rice straw under solid state fermentation. Our study revealed that unlike Trichoderma sp. that is normally associated with low amounts of ß-glucosidase, insufficient to perform an efficient hydrolysis, T. harzianum SNRS3 could be considered as a potential ß-glucosidase producer, but not an efficient xylanase producer. As a result of storage of the crude cellulase at room temperature, ß-glucosidase activity only decreased to above 80% of its original activity at the end of the 3rd week of storage. The crude cellulase produced by T. harzianum SNRS3 could be industrially applied as the enzyme is still highly active at 60°C and over a wide range of acidic pH.
Trichoderma, Aspergillus, rice straw, cellulase, solid state fermentation, characterisation
Sugarcane is one of the important crops that needs plentiful water in tropical and semi-tropical regions. This crop is widely grown in Khuzestan province of Iran. In this study, triple-row planting of sugarcane was evaluated and compared to double-row planting as currently being practiced in the region. Results showed that in spite of the higher density planting in triple-row planting, there was no significant difference between triple-row planting and double-row planting in terms of leaf sheath moisture, leaf nitrogen, ridge EC, qualitative situations of cultivar, plant height and stem diameter. However, the number of shoots and stems per m2 in the triple-row planting were found to be higher than in the double-row planting and the difference between them was significant at 5% level. In addition, water application efficiency, water use efficiency (WUE), mean yield of sugarcane and sugar content in triple-row planting were higher than double-row planting.
The use of synthetic amino acids (methionine, lysine, threonine) makes the formulation of diets with minimum levels of crude protein possible. The objective of this study was to determine the effects of low crude protein diet with amino acids supplementation on the performance, egg production, small intestine villus height and faecal LAB and ENT count in laying hens. A total of 144 16-week old layer hens of Hisex brown were assigned to four dietary treatments: 17.5% CP (control); (ii) 17.5% CP; (iii) 17% CP; and (iv) 16.5% CP supplemented with amino acids. Treatment group supplemented 17% CP was significantly higher (P<0.05) in egg production than other groups. Nonetheless, there were no significant differences (P>0.05) in egg quality. Results showed significant differences (P<0.05) in both villi height and crypt depth in duodenum, jejunum and ileum. The treatment supplemented with 17% CP showed a significant reduction (P<0.05) in faecal pH compared to the other groups. There was a significant different (P<0.05) in LAB and ENT count and LAB/ENT ratio among the dietary treatments. In conclusion, 17% CP treatment supplemented with amino acids demonstrated the best effects in improving the hens' egg production, small intestine villus height and even promoting beneficial effects of faecal microflora.
Medicinal plants play a major role in many cultures, not only as medicines, but also as trade commodities to fulfil the demands of distant markets. A study was conducted to characterise growth-promoting bacteria from two varieties of Kacip Fatimah (Labisia pumila) found at two different locations, Sungai Tekala, Semenyih, Selangor for Labisia pumila var. lanceolata and Bukit Slim Permanent Forest Reserve, Perak for Labisia pumila var. alata. Soil and plant samples were taken for the physico-chemical analyses and characterisation of the indigenous plant growth-promoting bacteria (PGPB). Both Labisia varieties were found to thrive in areas with quite similar soil chemical and physical properties in natural forest environments except for altitude, where Labisia pumila var. alata was found in higher elevation compared to Labisia pumila var. lanceolata. The soil in both places was found to be slightly acidic and low in nutrient content. Total bacterial population found on var. alata was higher than in var. lanceolata and the highest population was found in the root endosphere (8.68 × 107 cfu g-1 soil). Morphologically-isolated bacteria were circular in shape, with flat/raised elevation, entire margin, moist texture and smooth and glistening surface but varied in colour and size. Most of the bacterial strains showed several plant-growth promoting traits like plant-growth hormones (indole acetic acid (IAA)), N2 fixation and P solubilisation activities and beneficial enzymes. Two of the bacterial isolates showing most of the beneficial properties were identified as Exiguobacterium sp. and Stenotrophomonas sp. These PGPB have the potential to enhance the growth of Kacip Fatimah.
This study was conducted to investigate the effects of prepared probiotic (PP) on the live body weight, weight gain, feed intake and feed conversion ratio in Malaysian chicken (Akar Putra). A total of 72 day-old Akar Putra chicks were reared for 12 weeks and randomly assigned to three dietary treatments (24 chicken/treatment), with 3 replications for each (8 chicken/replicate). The treatments consisted of a control group (T1), and the supplemented diet with probiotic in the second treatment was prepared at the rate 1:1 (1 kg of commercial broiler feed + 1 g PP). While the rate was 1:2 (1 kg of commercial broiler feed + 2 g PP) in the third treatment. Supplementing probiotic in both rates revealed significant improvement in terms of males' and females' growth rates, final live body weight, weight gain and feed conversion ratio. Based on the research findings, the best results were obtained when chickens received 1 g PP in males and 2 g in females.
Akar Putra chicken, probiotic, production performance
The present experiment was conducted to evaluate the effects of wet feed and fermented feed on the intestinal morphology and histology of broiler chicks. A total of 360 one day old Ross 308 broiler chicks were randomly assigned (CRD) into six treatment groups. Chicks were fed: (T1) Control group of dry feed; (T2) Fed on wet feed (1:1, feed: water); (T3) 25% fermented feed + 75% dry feed; (T4) 50% fermented feed + 50% dry feed; (T5) 75% fermented feed + 25% dry feed and (T6) 100%, fermented feed throughout the experimental period. Each treatment group was replicated three times using 20 chicks per replicate. The chicks were raised at a temperature and in humidity controlled room with a 24-h. constant light and had ad. libitum access to water and feed throughout the experimental period which lasted for six weeks. The results showed that all diets containing fermented feed, especially 100%, had dependent effects on the evaluated production characteristics. The feeds had significantly (P < 0.05) increased the relative weight and length of the small intestine. Likewise, it raised the villi height, crypt depth and the percentage of the villi height to crypt depth in duodenum, jejunum and ileum increased. In conclusion, the results of the current experiment indicated that fermented feed with probiotic would be beneficial economically since the broiler feed conversion ratio had been improved (2.4% in T2; 4.1% in T3; 5.3% in T4; 5.3% in T5 and 7.7% in T6) as a consequence to enhance their intestinal morphology.
Research on watershed silica dynamics in Indonesia has been sparse as most of the focus on water environment has centred on suspended sediments, nitrogen and phosphorous. Thus, Si concentrations in rivers and their seasonal and spatial variations are not well understood. Silicon helps rice plants to overcome abiotic and biotic stresses by preventing lodging and increasing resistance against pests and diseases. Rice is one of the more important crops in the country, and information on Si concentrations in rivers is useful because river water is a primary irrigation source. In this study, we conducted a preliminary research on temporal and spatial variations in dissolved Si (DSi) concentrations at watershed scale to help achieve an efficient use of Si resources through irrigation water management. The Sumani Watershed, located approximately 50 km east of Padang City in West Sumatra, Indonesia, was selected as the target area. Lake Dibawah lies on the upstream end of the watershed, and water is discharged from the watershed into Lake Singkarak. The results verified that Lake Dibawah had a dam effect of naturally reducing DSi concentrations in water. In addition, the average DSi concentration from the samples obtained from rivers, small channels, and ditches from October 2013 to December 2014 did not show strong seasonal patterns at each site but revealed clear spatial differences among sub-watersheds linked to the groundwater from Mt. Talang. The watershed has a high capability of supplying DSi to paddy fields via irrigation water.
Irrigation water, lake watershed, DSi dynamics, sustainable rice production, humid tropical zone
Apparent metabolisable energy (AME) of palm oil (PO), soybean oil (SO), linseed oil (LO) and blend oil (BO) in a ratio of 4:1:1 were evaluated. A total of 75, 21-day-old birds were fed corn-soy basal diet and the four test diets containing different oil sources (PO, SO, LO and BO), that were developed by replacing 60 g/kg of the basal diet for eight days. Differences in the apparent metabolisable energy were found (P<0.05), with the higher values for broiler-fed BO. This study affirmed that BO increases AME of oil enriched with saturated fatty acid in poultry diets