Influence of irrigated agriculture on soil microbial diversity

Organic carbon (C), bacterial biomass and structural community diversity were measured in Southern Idaho soils with long term cropping histories. The soils tested were native sagebrush vegetation (NSB), irrigated moldboard plowed crops (IMP), irrigated conservation – chisel – tilled crops (ICT) and irrigated pasture systems (IP). Organic C concentration in soils decreased in the order NSB 0–5 cm > IP 0–30 cm = ICT 0–15 cm > IMP 0–30 cm > NSB 5–15 cm = NSB 15–30 cm. Active bacterial, fungal and microbial biomass correlated with soil C as measured by the Walkely Black method in positive curvilinear relationships (r² = 0.93, 0.80 and 0.76, respectively). Amplicon length heterogeneity (LH-PCR) DNA profiling was used to access the eubacterial diversity in all soils and at all depths. The Shannon–Weaver diversity index was used to measure the differences using the combined data from three hypervariable domains of the eubacterial 16S rRNA genes. Diversity was greatest in NSB 15–30 cm soil and lowest in the IMP soil. With the exception of IMP with the lowest diversity index, the samples highest in C (NSB 0–5 cm, IP 0–30 cm, ICT 0–15 cm) reflected lower diversity indices. However, these indices were not significantly different from each other. ICT and IP increase soil C and to some extent increase diversity relative to IMP. Since soil bacteria respond quickly to environmental changes, monitoring microbial communities may be one way to assess the impact of agricultural practices such as irrigation and tillage regimes.     

Fusarium equiseti is associated with the wilt and dieback of Aquilaria malaccensis in Northeast India

Aquilaria malaccensis, categorized by IUCN as globally vulnerable, is in high demand in the Middle East and Asian markets for its unique resinous agarwood. In August 2015, symptoms of dieback were observed on A. malaccensis trees planted in the Medicinal and Aromatic Plant Garden, Panbari, Golaghat of the Assam Forest Department. The entire crowns of 70 trees showed complete leaf loss and severe dieback. Rotting at the collar region and of roots was also observed. Isolation from the infected roots consistently yielded Fusarium equiseti identified following standard laboratory procedures and analysis of the internal transcribed spacer (ITS) sequence of the ribosomal DNA. Symptoms of wilt, dieback and root rot were observed on 5‐month‐old Aquilaria seedlings 25 days after inoculation with the isolated fungus. This paper is the first report of F. equiseti causing wilt and dieback of A. malaccensis.     

Attitudes of dog owners to neutering pets: demographic data and effects of owner attitudes

SUMMARY A survey of the attitudes of dog owners to desexing male and female dogs was conducted in the Brisbane area. Over 15800 replies (35% response) were returned for analyses and included both demographic and attitude data. The most common reasons given by owners for not having the dog desexed were that it was unnecessary or they wanted to breed from it or could not afford it or did not agree with it or that the dog was too old or it might get fat. Nearly twice as many male owners agreed that desexing male dogs removed maleness and also more males agreed with the question “Do you equate dog sexuality with human sexuality?” Female owners were more aware than males that their female dogs did not need to have a season (oestrus) or a litter before being desexed. More male owners thought that desexing changed a male or female dog's personality. A disturbing fact was that 61.1% of male owners and 47.3% of female owners would now not have their dog desexed if it had not already been done. More male than female dog owners were ignorant about whether desexing changed personality, made dogs frustrated, or if female dogs should have a season or a litter before desexing. The study showed a gender bias in owner attitudes to all the attitude questions.     

Influences of Follicular Size on Parthenogenetic Activation and in Vitro Heat Shock on the Cytoskeleton in Cattle Oocytes

The availability of cow ovaries from the slaughterhouse has been very limited in Taiwan. To maximize the use of cow ovaries for research purposes, whole ovary dissection was performed and the developmental competence of the oocytes derived from different sizes of follicles was assessed by the rates of in vitro maturation (IVM) and parthenogenetic activation of the oocytes in Experiment 1 (Exp 1). Cumulus-oocyte complexes (COCs) derived from small (1-2 mm) and large (3-8 mm) follicles were subjected to standard IVM culture for 24 h. Mature oocytes were selected and then parthenogenetically activated using A23187 (5 microm, 5 min) or thimerosal (200 microm, 10 min) alone or combined with 6-dimethylaminopurine (2.5 mm and 3.5 h, respectively). Activation rates of the oocytes, neither from the large nor small follicles, were affected by different activation treatments (single or combined stimuli). Whereas maturation rates for the oocytes from large follicles were superior to those from small follicles in both the single (59% vs 45%) and combined treatments (76% vs 40%; p < 0.05). To understand how prolonged heat shock (HS) influences cytoskeletal configurations of mature bovine oocytes, in Experiment 2 (Exp 2), matured oocytes derived from large follicles were randomly allocated to different durations of HS treatments at 41.5 degrees C for 0 (C0h, control, n = 12), 1 (HS1h, n = 28), 2 (HS2h, n = 31), and 4 h (HS4h, n = 30). An additional control group was cultured for 4 h without HS (38.5 degrees C, 4 h, n = 35). Alterations in nuclear structures, microtubules (MTs), and microfilaments (MFs) of the oocytes were examined. Abnormalities in the chromosomes, spindle MTs and the percentages of oocytes with cytoplasmic MTs increased with time of HS treatment. The intensity of the MF distribution in the HS oocytes was also altered. Significant changes in the cytoskeleton after HS may be associated with the reduced development under hyperthermia and, perhaps, with the low pregnancy rates of the animals during hot seasons.     

Successful Low Dose Insemination of Flow Cytometrically Sorted Ram Spermatozoa in Sheep

The fertility of ram spermatozoa that had undergone flow cytometric sorting (MoFlo SX) and cryopreservation was assessed after low-dose insemination of synchronized Merino ewes. Oestrus was synchronized with progestagen-impregnated pessaries, PMSG and GnRH treatment. Ewes (n = 360) were inseminated with 1 x 10(6), 5 x 10(6) or 15 x 10(6) motile sorted frozen-thawed (S(1), S(5), or S(15) respectively) or non-sorted frozen-thawed (C(1), C(5) or C(15) respectively) spermatozoa from three rams. An additional group of ewes were inseminated with 50 x 10(6) motile non-sorted frozen-thawed spermatozoa (C(50)) to provide a commercial dose control. The percentage of ewes lambing after insemination was similar for C(50) (24/38, 63.2%), C(15) (37/54, 68.5%), S(15) (38/57, 66.7%), S(5) (37/56, 66.1%) and S(1) (32/52, 61.5%) groups (p > 0.05), but lower for C(5) (19/48, 39.6%) and C(1) (19/55, 34.5%) treatments (p < 0.05). This study demonstrates sorted ram spermatozoa are equally fertile to non-sorted spermatozoa even when inseminated at 2% of the dose. Furthermore, at very low artificial insemination doses (1 or 5 million motile) the fertility of sorted ram spermatozoa is superior to non-sorted spermatozoa inseminated in equal numbers. These results have significance for the future commercialization of sex-preselection technology in sheep as a reduction in the minimum effective sperm number will allow a corresponding decrease in the associated cost per dose.     

Effect of restricted feeding and refeeding on compensatory growth,nutrient utilization and gain,production performance and whole body composition of carp cultured in earthen pond

To assess the compensatory growth, a 10‐month pond experiment was conducted in which three species of Indian major carps, viz. Catla catla, Labeo rohita and Cirrhinus mrigala (1 : 1 : 1), were stocked at 7500 ha^?1 and the fish were subjected to different restricted feeding and refeeding protocols, viz. Control (C): Continuously fed for 10 months; Treatment‐1 (T‐1): Initial supplementary feeding for 2 months+ No supplementary feeding for 1 month + Refeeding for 7 months; Treatment‐2 (T‐2): Initial supplementary feeding for 2 months + No supplementary feeding for 2 months + Refeeding for 6 months; and Treatment‐3 (T‐3): Initial supplementary feeding for 2 months + No supplementary feeding for 3 months + Refeeding for 5 months in triplicate ponds. At the end of experiment, 100% growth compensation was achieved in T‐2 for all the three carp species. Among all treatments, higher weight gain, PER and PPV and lower AFCR were also recorded in T‐2, resulting in maximum fish production. The restricted feeding had significant effect (P < 0.05) on whole body chemical composition of fish. From this study, it is concluded that in 10‐month pond culture of carp in fertilized pond, the T‐2 would be the best and most economic feeding strategy.     

Antioxidant potential of medicinal plants

Journal of Crop Science and Biotechnology - Medicinal plants are used for health care either directly or indirectly as they are rich source of several ingredients. Ethno-medical traditions prove...     

Length–weight relationship and growth performance of different life stages of hatchery‐produced magur,Clarias magur (Hamilton, 1822)

Length–weight relationship (LWR) of 661 numbers of hatchery‐produced magur, Clarias magur of all the life stages such as hatchlings, fry, fingerlings, juveniles and adults, was studied. The LWR of all the life stages of magur was estimated and the equations are as follows, hatchlings W = 0.0052*L^1.282 (r² = 0.8784), fry W = 0.0088*L^3.028 (r² = 0.8113), fingerlings W = 0.0065*L^3.226 (r² = 0.8906), juveniles W = 0.0028*L^3.420 (r² = 0.8175) and adults W = 0.0017*L^3.491 (r² = 0.8310). A positive allometric growth (b > 3) was observed in all the life stages except hatchlings. The annual growth rate of magur was observed with the body length and weight of 24 ± 1 cm and 115 ± 17 g, respectively, under the commercial production system. This is the first kind of study that describes about the LWR and growth performance of all the life stages of hatchery‐produced C. magur catfish from hatchlings to adults under commercial production system. This study will be more useful to the hatchery managers and fish growers to optimize the resources and husbandry practices to improve the growth, survival, and biomass production.