Effects of Stocking Density and Monosex Culture of Freshwater Prawn Macrobrachium rosenbergii on Growth and Production in Concrete Tanks in Saudi Arabia

Abstract This study was conducted to evaluate the effects of stocking density and monosex culture on growth, survival, yield and feed conversion ratio of freshwater prawn Macrobrachium rosenbergii in concrete tanks. Juvenile prawns with an average weight of 1.8 g were stocked into triplicate tanks at densities of 5, 10, 15 and 20 prawns/m², grown for 168 d and fed a 34% tilapia diet. Stocking density had significant effect on prawns. Final mean body weight decreased with the increasing density, being highest at 5 prawns/m² (29.6 9). and lowest at 20 prawns/m² (17.4 g). Total yield increased from 135 g/m² (1,350 kg/ha) at a density of 5 prawns/m² to 261 g/m² (2,610 kg/ha) at density 15/m^z to 245 g/m² (2,450 kg/ha) at 20/m^z. Feed conversion ratios were high and ranged from 3.7 (5 prawns/m²) to 5.6 (20 prawns/m²).
In monosex culture of freshwater prawns stocked in triplicate tanks at a density of 5 prawns/m² for 112 d, the all-male population had the best growth performance and feed conversion ratio, followed by the mixed-sex and all-female populations. The all-male population had 99% marketable prawns (>20 g) with an average yield of 159 g/m² (1,590 kg/ha); the mixed-sex population had 90% marketable prawns and the yield was 135 g/m^z (1,350 kg/ha); and the all-female population had 75% marketable prawns with an average yield of 108 g/m² (1,080 kgha).     

Interaction between Eimeria uzura infection and aflatoxicosis in Japanese quail (Coturnix coturnix japonica)

The clinical signs and gross lesions caused by Eimeria uzura (10(5) oocysts) in Japanese quail (Coturnix coturnix japonica) exhibited little or no influence in the face of intercurrent dietary aflatoxicosis (1 p.p.m. of aflatoxin B1 from Day 0 to 55). Similarly, no significant differences in the mucosal morphology of the intestine were evident histologically between the two groups of Japanese quail. The nervous signs of ataxia, leg weakness, incoordination of movement, torticollis and terminal opisthotonos were toxin-induced manifestations. In the aflatoxic quail, hypoplastic changes and selective depletion of lymphocytes were more prominent in the bursa of fabricius. Increased relative mean weights of liver, kidney, spleen, crop, proventriculus and gizzard were observed in birds due to aflatoxin sensitivity. The combination of E. uzura infection and aflatoxicosis in Japanese quail may cause significant weight loss, and increased oocyst production and reproductive potential.     

Investigations on the antinociceptive activity of crude extracts from Croton cajucara leaves in mice

The crude leaf extracts of Croton cajucara Benth. were studied for their antinociceptive property in chemical and thermal models of nociception in mice. All the tested extracts (hexanic, chloroformic and methanolic), at oral doses of 100 and 200 mg/kg demonstrated significant inhibition of acetic acid-induced writhing and the second phase response of formalin, but did not manifest a significant effect in hot-plate test.     

A study of the potential of hedgerow intercropping in semi-arid India using a two-way systematic design

The potential of hedgerow intecrropping with Leucaena leucocephala was explored on vertic Inceptisols over 4 years at ICRISAT Center, Patancheru, India. The study was conducted using a systematic layout involving different alley widths ranging from 1.35 to 4.95 m and with varying distances between hedge and crops. The alleys were cropped with alternate rows of sorghum and pigeonpea. Hedges composed double Leucaena hedgerows 60 cm apart were periodically harvested for fodder. Sole crops of all components and a sorghum/pigeonpea intercrop were included in all four replications of the study.Starting in the second year, Leucaena was progressively more competitive to annual crops, causing substantial yield reduction. Competition (primarily for moisture) was most severe in narrow alleys and was greatest on pigeonpea.The growth of Leucaena was not sufficient to compensate for reduced crop yields. Land equivalent ratios (LERs) calculated on the basis of grain yield of crops and Leucaena fodder yields showed that hedgerow intercropping (HI) was advantageous over sole crops only during the first two years using wide alleys, but disadvantegeous in the last two years. LERs calculated on the basis of total dry matter indicated only a small advantage for HI (13–17 percent) over sole crops in wider (>4 m) alleys. Average returns per year from HI exceeded those of the most productive annual crop system (sorghum/pigeonpea intercropping) by 8 percent in 4.05 m alleys, and by 16 percent in 4.95 m alleys. Fodder production during the dry season was 40 percent of the annual total in these alley widths. Thus hedgerow intercropping at 4–5 m alley width is not very attractive for farmers in semi-arid India, which has 600–700 mm of annual rainfall. There is a need to examine the potential of HI in wider alleys. The merits and limitations of the systematic design are discussed.     

喀布尔动物园并非动物的避难所

在阿富汗首都喀布尔的西南部，在飞扬的尘土和战后满目疮痍的城市里，幸运地保留着一块绿树葱茏的清凉绿洲，那就是喀布尔动物园。然而，动物园里并非一派安宁平和，那儿的动物对它们的生存状况极其愤怒，管理员们同样也很生气。     

厚朴矮林经营技术的初步研究

厚朴伐桩有很强的萌蘖能力，在生长季节采伐也能得到满意的萌芽更新效果，每个伐桩可萌发1－7个萌芽条，7年生厚朴矮林的树干与树枝鲜重达60.2t.hm^-2，平均净生产量为8.6t.hm^-2.a^-1，表明厚朴完全适宜矮林经营，伐桩高度对萌芽条数量，矮林生长影响不大；伐桩萌芽条数量越多，矮林生长越好。     

A new phorbol diester from Aleurites moluccana

A new phorbol diester, 13-O-myristyl-20-O-acetyl-12-deoxyphorbol (1), has been isolated from the benzene extract of the heartwood of Aleurites moluccana. In addition, hentriacontane, 6,7-dimethoxycoumarin, 5,6,7-trimethoxycoumarin and beta-sitostenone are being reported for the first time from this species.     

Monoclonal antibodies specific to thermostable proteins in animal blood

Bovine plasma proteins are used as high-quality protein supplements in animal feed and as binders or colorants in food for human consumption. Religious observance, as well as recent fears of epidemic bovine spongiform encephalopathy, highlights the need for methods to detect bovine blood in processed food and animal feed for regulatory purposes, as the currently available methods are neither species-specific, blood-specific, nor valid for excessively heat-processed samples. This paper reports the development of monoclonal antibodies (MAbs) raised against bovine thermostable plasma proteins that display a unique species specificity pattern for plasma proteins. Immunoblotting revealed several thermostable antigenic proteins (10, 25, 40, and 60 kDa) in bovine plasma sterilized at 121 degrees C for 15 min. These MAbs can be employed individually or combined in immunoassays for analytical purposes and investigations of the chemical and biological properties of the thermostable plasma proteins identified here.