Effects of a short‐term supranutritional selenium supplementation on redox balance,physiology and insulin‐related metabolism in heat‐stressed pigs

Heat stress (HS) disrupts redox balance and insulin‐related metabolism. Supplementation with supranutritional amounts of selenium (Se) may enhance glutathione peroxidase (GPX) activity and reduce oxidative stress, but may trigger insulin resistance. Therefore, the aim of this experiment was to investigate the effects of a short‐term high Se supplementation on physiology, oxidative stress and insulin‐related metabolism in heat‐stressed pigs. Twenty‐four gilts were fed either a control (0.20 ppm Se) or a high Se (1.0 ppm Se yeast, HiSe) diet for 2 weeks. Pigs were then housed in thermoneutral (20°C) or HS (35°C) conditions for 8 days. Blood samples were collected to study blood Se and oxidative stress markers. An oral glucose tolerance test (OGTT) was conducted on day 8 of thermal exposure. The HS conditions increased rectal temperature and respiration rate (both p < .001). The HiSe diet increased blood Se by 12% (p < .05) and ameliorated the increase in rectal temperature (p < .05). Heat stress increased oxidative stress as evidenced by a 48% increase in plasma advanced oxidized protein products (AOPPs; p < .05), which may be associated with the reductions in plasma biological antioxidant potential (BAP) and erythrocyte GPX activity (both p < .05). The HiSe diet did not alleviate the reduction in plasma BAP or increase in AOPPs observed during HS, although it tended to increase erythrocyte GPX activity by 13% (p = .068). Without affecting insulin, HS attenuated lipid mobilization, as evidenced by a lower fasting NEFA concentration (p < .05), which was not mitigated by the HiSe diet. The HiSe diet increased insulin AUC, suggesting it potentiated insulin resistance, although this only occurred under TN conditions (p = .066). In summary, HS induced oxidative stress and attenuated lipid mobilization in pigs. The short‐term supranutritional Se supplementation alleviated hyperthermia, but did not protect against oxidative stress in heat‐stressed pigs.     

Genetic analysis of ratooning ability of rice (Oryza sativa L.)

Summary Genetic analysis of generation means of F₁, F₂, F₃, F₄, and the parental populations of the cross IR10154-23-3-3A/IR15795-232-3-3-2 for ratooning ability was conducted. Good ratooning ability is a recessive trait. The parents differed by at least two pairs of major genes for ratooning ability. A large proportion of transgressive segregants in F₂ suggested that the expression of ratooning ability is influenced not only by major genes but also by modifiers. Broad-sense heritability estimates computed by different methods ranged from 0.66 to 0.88. Narrow-sense heritability by the F₄–F₃ regression method was 0.39. The heritability estimates were 0.42 and 0.33 by the variance component method. The prevalence of additive x additive type of gene effects along with prominent additive effects imply some scope for selection in the segregating generations. However, non-additive type of gene action also affects the expression of ratooning ability.     

Comparison of tiletamine-zolazepam-ketamine and tiletamine-zolazepam-ketamine-xylazine anaesthesia in sheep

Summary The anaesthetic effects of intravenous tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg (TK) and tiletamine-zolazepam 6.6 mg/kg-ketamine 6.6 mg/kg-xylazine 0.11 mg/kg (TKX) were evaluated in six wethers. Heart rate, respiration rate, arterial blood pressure, and the electrocardiogram were monitored during anaesthesia. Analgesia was tested by electrical stimulation in the left flank. Atropine (0.03 mg/kg) was given intramuscularly before induction, but after recording of baseline heart rate and respiratory rate. The duration of analgesia was 28.7 ± 6.9 min with TK and 82.8 ± 26.6 min with TKX. Heart rate increased significantly within 5 min after TK or TKX administration. Respiratory rate remained unchanged after TK administration, but increased significantly from 5 to 45 min after TKX administration. Arterial blood pressure decreased significantly at 15 min with TK and 30 min with TKX. Sheep remained recumbent for 201 min with TK and 166 min with TKX. All recovered uneventfully. We conclude that either TK or TKX may be used for anaesthetising sheep.     

Pyometra in camels: case report.

Pyometra was recorded in five camels and Actinomyces pyogenes (Corynebacterium pyogenes) was isolated from pus of the affected camels.     

In vivo immunosuppression by synthetic pyrethroid (cypermethrin) pesticide in mice and goats

Cypermethrin toxicity was produced in mice by intra-peritoneal injection of the pesticide at 50 mg/kg body weight per day for 26 days, and in goats by drenching with cypermethrin at 41.6 mg/kg body weight per day for 30 days. The status of cell-mediated immunity (CMI) was assessed by the 2,4-dinitrofluorobenzene (DNFB) skin sensitivity test. The results indicated significant depression of CMI in the cypermethrin-treated mice and goats. In addition, the humoral immune reaction of the goats intoxicated with cypermethrin was estimated by enumeration of the plaque-forming B-lymphocytes. The rate of plaque formation in the lymphocyte suspension of cypermethrin-treated goats was significantly reduced and the diameter of the plaques was also significantly lower than in that of control animals. The results indicated that cypermethrin suppressed both CMI and the antibody-forming ability of lymphocytes. This immunosuppressive action of cypermethrin is being reported for the first time.     

Physiological Basis of Yield Variation in Short-duration Pigeonpea Grown in Different Environments of the Semi-Arid Tropics1

Five short-duration pigeonpea (Cajanus cajan (L.) Millsp.) genotypes were grown at three plant populations in three locations during the 1986 and 1988 rainy seasons, to determine the physiological basis of observed variations in yield. Significant differences were found in seed yield (Y), crop growth rate (C), and the durations of vegetative (Dv) and reproductive (Dr) growth, and partitioning (P). These were attributable to genotypes and their interactions with environments (except for C). Variation in C, Dr, and P together explained 78 % of the observed variation in Y due to different genotypes and environments. Crop growth rate alone contributed about 71 % of the variation in Y, and reached an optimum value of around 6.5 kg ha^?1°Cd^?1. Crop growth rates increased with the duration of the vegetative period and with plant population. However, a negative relationship between C and P resulted in plant population having little effect on seed yield. The maximum-yielding genotype, ICPH 8 had the highest C and an intermediate P.     

Water table behaviour in drained lands: effect of evapotranspiration from the water table

Subsurface drain spacing is underestimated by the equations that do not account for evaporation-evapotranspiration (ET) lowering the water table in drained lands. An analytical solution is proposed to evaluate water table behaviour in subsurface drained lands in the presence of ET. A piecewise linear model is proposed and used to describe any realistic functional relation between ET and depth to water table. Characteristics of the solution have been highlighted with the help of numerical examples for which drainage parameters have been chosen from two actually operating drainage systems installed in semi-arid regions. The accuracy of the proposed solution has been verified with the existing numerical scheme as well as by comparing the water table behaviour with the observed field data. Application of the solution in subsurface drainage design has been illustrated which suggests that drain spacing at this particular site could be increased by 9 to 18% if the contribution of ET in lowering the water table is taken into account.     

Molecular markers to distinguish ‘Thar Shoba’, a variety of khejri [Prosopis cineraria (L.) Druce], from trees in natural populations

Prosopis cineraria (L.) Druce, commonly called khejri, is an important multipurpose, leguminous tree of the Thar Desert. ‘Thar Shoba’ is a variety of khejri without thorns which was developed as a vegetable. In order to develop markers for varietal identification, 80 RAPD primers were tested, of which nine were polymorphic between ‘Thar Shoba’ and trees in a natural population of khejri. Phenetic analysis revealed that ‘Thar Shoba’ formed a separate cluster from the natural population with similarity coefficients of 0.57–0.78. The 10-mer primers OPBE05, OPBA13, OPA12, and OPA14 were each found to differentiate ‘Thar Shoba’ from the natural population by one amplicon. These differential amplicons were sequenced and SCAR markers were developed based on the sequences that differentiated ‘Thar Shoba’ from the natural population. Natural populations of khejri from different regions of the Thar Desert, and clonally multiplied ‘Thar Shoba’ plants in the ICAR-CIAH bud-wood genebank, were used to validate these primers. These markers will be useful in further developing the bud-wood genebank, and for certification, identification, and protection of the khejri variety ‘Thar Shoba’.