Influence of different diets on the growth,survival, fecundity and proximate composition of brine shrimp Artemia franciscana (Kellog, 1906)

Artemia franciscana was studied under in vitro conditions, and fed with five different microalgae species, two organic diets and one mixed diet to evaluate the nutritional profile and growth performance. The A. franciscana instar‐I nauplii were stocked at a density of 100 per litre of ground borewell water with a salinity of 70 ppt in a plastic container and the culture continued for 12 days. The A. franciscana was fed with five microalgal species, such as Tetraselmis sp., Chaetoceros sp., Isochrysis sp., Thalassiosira sp. and Nannochloropsis sp., and organic diets of rice bran, soybean meal, and a mixture of Tetraselmis sp. and Chaetoceros sp. with rice bran, giving a total of eight experiments. The growth of A. franciscana was measured by length, and was observed to be the greatest (10,850 μm) in the group that was fed the mixed algae combination, and the lowest (7,290 μm) in the group that was fed Nannochloropsis sp. Among the different treatments, the highest survival value of 76% was seen in the group that was fed Chaetoceros sp. The fecundity was higher in A. franciscana that were fed with algae Chaetoceros sp., while the lower rate was observed with the group that was fed Nannochloropsis sp. Analysis of proximate composition showed increased levels in the animals fed with Chaetoceros sp. (lipid, 19.40%; eicosapentaenoic acid, 6.70 mg; docosahexaenoic acid, 10.20 mg; amino acids: proline, 2.06 μg; histidine, 0.77 μg, arginine, 0.65 μg, glycine, 0.80 μg, glutamic acid, 1.75 μg; threonine, 1.42 μg) and the mixed diet (protein, 58.59%; carbohydrate, 21.30%; amino acids: asparagine, 0.90 μg; serine, 1.65 μg; tryptophan, 1.66 μg; leucine, 1.50 μg; phenylalanine, 1.14 μg; valine, 0.66 μg). All components showed the lowest level in the diet fed with Tetraselmis species. These A. franciscana populations showed better survival, higher fecundity and biochemical profiles when cultured with microalgae Chaetoceros sp. These data are useful to improve A. franciscana culture in aquaculture to produce quality cysts and biomass, especially in feeding larvae of marine species.     

Tissue culture and <Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated genetic transformation studies in four commercially important indica rice cultivars

This research was undertaken to find an efficient tissue culture system and Agrobacterium-mediated genetic transformation method for recalcitrant indica rice cultivars. For this, mature seeds of commercially important indica rice varieties, ASD16, ADT43, IR 64, and Pusa Basmati were cultured on MS and N6 medium supplemented with 2 mg l^-1 2, 4-D + 30 g l^-1 sucrose. The calli grown in N6 medium showed better friability and embryogenic response. Out of the four varieties tested, ASD16 and IR64 showed better callusing and embryogenic capacity as compared to ADT43 and Pusa Basmati. For genetic transformation studies, embryogenic calli of all the cultivars were co-cultivated with the Agrobacterium tumefaciens strain LBA 4404 harboring the binary vector pCambia 1305.1 with GUS gene. GUS assay was performed for the putative transformed calli and its activity was found to be qualitatively higher in ASD16 and IR64 than the other two varieties. The best responsive ASD16 transformed calli was regenerated and the putative transgenic lines were regenerated. ASD16 transformed calli were confirmed by GUS assay. PCR analysis confirmed the presence of both GUS and HPT genes in ASD16 transgenic lines.     

Specific immune response in mucosal and systemic compartments of Cirrhinus mrigala vaccinated against Edwardsiella tarda: In vivo kinetics using different antigen delivery routes

Mucosal immune barriers confer protection against invading fish pathogens. Here, we conducted an experiment for 60 days to assess the mucosal and systemic immune response in Mrigal (Cirrhinus mrigala), an Indian major carp. Fish were immunized with inactivated Edwardsiella tarda by four different routes, namely, oral, immersion, injection, and anal intubation. An indirect enzyme‐linked immunosorbent assay (ELISA) was used to measure the specific immune response (antibody) in serum and mucus (collected from skin, gill, and gut) of the fish on 0, 15, 30, 45, and 60 days postimmunization. For specific immune response in the serum, significantly higher (p < 0.05) optical density (OD) values were obtained in the anal group (0.52 ± 0.03) and in the oral group (0.48 ± 0.03). In the skin mucus, significantly higher OD values were obtained in the oral group (0.48 ± 0.04) and immersion group (0.32 ± 0.03). In the gill mucus, significantly higher OD values were obtained in the oral group (0.82 ± 0.08) and the immersion group (0.73 ± 0.03). In the gut mucus, significantly higher OD values were obtained in the immersion group (0.080 ± 0.007) compared to the rest of the treatments. Fish from all the groups were challenged with LD₅₀ dose of E. tarda at the end of the experiment. We conclude that oral and immersion immunization routes offer better protection of C. mrigala compared to other antigen delivery routes.     

Pheromones in the Management of Major Lepidopterous and Coleopterous Pests of Cotton

Cotton is infested by over 30 pests belonging to lepidoptera and coleoptera. Amongst these insects, various bollworms and cotton boll weevil cause economic damage every year. In IPM, pheromones are considered to be an essential component because they are used for detecting the economic threshold levels of pest populations and for mating disruption as a direct pest suppression measure. Pheromones of major pests have been found to be effective, economic and eco-friendly in agro-ecosystems in which cotton is cultivated.     

The efficacy of praziquantel (Droncit R) against Raillietina tetragona (Molin, 1958) in domestic fowl

The efficacy of different dose rates of Praziquantel (Droncit R) in tablet and liquid (injectable) form against Raillietina tetragona in the domestic fowl was studied. A dose of 10 mg kg-1 of Praziquantel in tablet form and 0.15 ml kg-1 in liquid form was found to be effective against R. tetragona infection irrespective of age, sex and intensity of infestation of the host. Intramuscular (IM) administration of liquid Praziquantel was found to be more effective than subcutaneous (SC) administration. Susceptibility of the parasite to this drug increased with age.     

Gray wolf (Canis lupus) is a natural definitive host for Neospora caninum

The gray wolf (Canis lupus) was found to be a new natural definitive host for Neospora caninum. Neospora-like oocysts were found microscopically in the feces of three of 73 wolves from Minnesota examined at necropsy. N. caninum-specific DNA was amplified from the oocysts of all three wolves. Oocysts from one wolf were infective for the gamma interferon gene knock out (KO) mice. Viable N. caninum (designated NcWolfUS1) was isolated in cell cultures seeded with tissue homogenate from the infected mouse. Typical thick walled tissue cysts were found in outbred mice inoculated with the parasite from the KO mouse. Tissue stages in mice stained positively with N. caninum-specific polyclonal antibodies. Our observation suggests that wolves may be an important link in the sylvatic cycle of N. caninum.     

White spot syndrome virus (WSSV) infection in tiger shrimp <Emphasis Type="Italic">Penaeus monodon</Emphasis>: A non-lethal histopathological rapid diagnostic method using paraffin and frozen sections

White spot syndrome virus (WSSV) infection was induced in tiger shrimp, Penaeus monodon, under laboratory conditions, and histopathological changes in subcuticular epithelial cells of the eye stalk and pleopod were studied sequentially at different time post-challenge. Routine histological techniques using paraffin embedded tissues, as well as frozen tissues, were used to document WSSV infection. Histological manifestations such as cellular hypertrophy in the subcuticular epithelial cells of the eyestalk and pleopod could be detected as early as 18 h post-infection (p.i.) before the manifestation of clinical signs of the disease. However, no histopathological changes could be detected before 18 h p.i.. Hypertrophy of the nuclei in the epithelial cells was pronounced after 24 h p.i. Marked necrosis, and eosinophilic intranuclear inclusions, characteristic of early stages of WSSV infection were observed between 24–36 h p.i. Clinical signs of the disease appeared at 48 h p.i. The presence of WSSV at early asymptomatic stages of p.i. has been tested in parallel samples using polymerase chain reaction, for further confirmation of WSSV. This paper discusses the potential of a non-lethal and rapid histopathological diagnostic method to document WSSV infection, using the eyestalk or pleopod, when expensive DNA based diagnostics are not available or affordable.     

Spatial and temporal variations of sediment quality in and around fish cage farms: A case study of aquaculture in the Seto Inland Sea, Japan

ABSTRACT: Fish cage farming generates large amounts of organic waste in the form of unconsumed feed and fecal matter, resulting in sediment deterioration and a threat to its own sustainability. Field studies analysed the scale of the impact of fish cage farming on sediment quality, variability of impact and spread of sediment enrichment in the vicinity of a fish farm. Two fish culture sites near the Fukuyama area of the Seto Inland Sea of Japan were chosen for the study. There was a significant difference between the quality of the sediment in aquaculture and non-aquaculture areas. The sediment underlying the fish cage farms was found to be extremely reducing, acidic and sulfidic. Sediment ignition loss did not vary markedly with the season. However, the redox potential and acid volatile sulfide content of aquaculture areas did show some seasonal variation. Sediment encircling a 165 m radius from the center of a farm in Yokota was judged as organically enriched by fish farming. A variation in sediment quality within the two sites and also within the stations was observed. Based on sediment quality, the stations could be categorized as less affected, highly affected or moderately affected.     

Slaughterhouse prevalence of ovine paratuberculosis in Southern India

Ovine paratuberculosis is a threat to small animal holders in terms of economic loss such as reduced growth performance and early culling. In order to study the slaughterhouse prevalence of ovine paratuberculosis, the slaughterhouse sheep samples (which are poor in body condition) collected over a period of two and half years from 1,034 suspected male sheep (poor in body condition) and 40 normal sheep (good body condition and subsequently negative by all the diagnostic tests employed) aged between 16 and 18 months were slaughtered at various abattoirs of Tamil Nadu. All the sheep taken in this study were maintained in almost same management conditions. DNA was extracted from 1,034 intestinal tissue and mesenteric lymph node and 121 were positive by IS 900 PCR. One hundred ten and 56 were positive by absorbed ELISA and Ziehl–Neelsen staining, respectively. In histopathology, 28 animals showed gross lesions of paratuberculosis infection (20—multibacillary and 8—paucibacillary forms). Out of 1,034 sheep tissues cultured, 32 showed cultural growth in Middlebrook 7H9 and 26 in Herrold's egg yolk medium. None of the 40 normal sheep were positive by any of the tests employed. In general, the mean body weight of paratuberculosis-affected animal either by any one of the tests employed was less than the non-affected sheep. The approximate economic loss per sheep/farmer/year is around Rs 1,840 (US$ 38.33) in paratuberculosis-affected sheep.     

Novel report on mutation in exon 3 of myostatin (MSTN) gene in Nilagiri sheep: an endangered breed of South India

Tropical Animal Health and Production - The variability in breeding program leads to rapid loss of genetic potential for which National Bureau of Animal Genetic Resources is emphasized to conserve...