Assessment of Genetic Variability in the Coding Sequence of Melatonin Receptor Gene (MTNR1A) in Tropical Arid Sheep Breeds of India

Seasonal behaviour in sheep, which varies in tropical and temperate environmental conditions, is a matter of study, because it can provide a clue to address the problem of seasonality in sheep. Melatonin receptor is the membrane‐bound G‐coupled receptor, sensing the message of photoperiodic cues thorough melatonin. Restriction fragment length polymorphism (RFLP) studies were carried out to assess the variability of gene at G612A and C606T SNPs in MTNR1A gene, which have been studied to be markers for out‐of‐season breeding. Allelic frequency distribution corresponded to higher frequency of GG and CC genotype, in tropical arid sheep breed in comparison with temperate region sheep breed. PCR amplification of MTNR1A gene of 30 animals was performed and single nucleotide polymorphisms (SNPs) identification was carried out using Lasergene software. Seven SNPs/mutations were identified, but most of them were synonymous, except the one G706A, leading to substitution of valine by isoleucine. Polyphen‐2 analysis of G706A mutation revealed that it is a benign mutation. Two important SNPs C426T and G555A, which were identified in temperate sheep breeds, could not be traced in Magra and Marwari breeds of sheep. Thus, the Magra and Marwari breeds of tropical, arid region demonstrated the presence of both polymorphic SNPs markers G612A and C606T, associated with out‐of‐season breeding. GG and CC genotypes were having a higher prevalence in the studied population.     

Ending overfishing while catching more fish

The world's seas and oceans are a vital source of animal protein from fishing and a major contributor to global food security. It has been argued that global wild‐catch production has reached its limit, and there is concern that many species are overfished. Concerns are also mounting about the state of marine ecosystems and the ecological impacts of fishing on them, with increasing efforts to protect marine biodiversity. Fisheries appear to be at an impasse – demand for seafood is rising but so is concern about the impacts of fishing. However, through a simple analysis, we show that global exploitation rates are well below long‐term sustainable levels at a whole ecosystem level. The oceans can support considerably higher sustainable catch than currently harvested. Overfishing has happened but only to a small fraction of species as a result of intensive and selective fishing. Shifting fishing effort away from highly targeted stocks towards currently underutilized species would reduce pressure on overfished species, result in fewer adverse ecosystem effects of fishing and increase overall fisheries production. This shift requires significant changes to our views about seafood, particularly in the developed world. We suggest ways in which this paradigm shift could happen and the range of expertise that would be required to achieve higher global yields with less ecological impact.     

Quantitative real-time PCR effectively detects and quantifies colonization of sclerotia of Sclerotinia sclerotiorum by Trichoderma spp.

Some members of the fungal genus Trichoderma are able to colonize and destroy sclerotia, the thick-walled resting structures of the soilborne plant pathogenic fungus Sclerotinia sclerotiorum, thus providing a potential means of biological disease control. However, current methods to detect and quantify colonization of sclerotia are labor-intensive, and generally qualitative rather than quantitative in nature. Our objective was to develop quantitative real-time PCR (polymerase chain reaction) methods to detect and measure colonization of sclerotia by Trichoderma spp. Specific PCR primer/probe sets were developed for Trichoderma spp. and for S. sclerotiorum. A total of 180 ITS1 (internal transcribed spacer) and ITS2 sequences from different species in the genus Trichoderma were aligned, and consensus sequences were determined. Six candidate primer sets were based on conserved regions of the consensus sequence, and the specificity of each nucleotide sequence was examined using BLAST (Basic Local Alignment Search Tool; NCBI) software. Each candidate primer set was tested on genomic DNA of T. harzianum strain ThzID1-M3, as well as six different Trichoderma isolates from soil, and on genomic DNA of S. sclerotiorum. The optimum primer/probe set selected, TGP4, successfully amplified genomic DNA of all Trichoderma isolates tested, and showed high precision and reproducibility over a linear range of eight orders of magnitude, from 85 ng to 8.5 fg of T. harzianum genomic DNA. TGP4 did not amplify S. sclerotiorum DNA. A specific PCR primer/probe set (TMSCL2) was developed for S. sclerotiorum, based on the calmodulin gene sequence. TMSCL2 did not amplify Trichoderma DNA. Quantitative real-time PCR with the primers then was evaluated in experiments to test differential effects of two soil moisture levels (−50 kPa, −1000 kPa matric potential) on biocontrol of S. sclerotiorum by indigenous Trichoderma spp. Periodically over 40 days, Trichoderma and S. sclerotiorum DNA in sclerotia were quantified by PCR with appropriate primers. Over 90% of the sclerotia were colonized by indigenous Trichoderma spp. at −1000 kPa, over the 40-day period, compared to only 60% at −50 kPa. In addition to determining incidence of colonization, the PCR method allowed measurement of the extent of sclerotial colonization, which also was significantly greater in the drier soil. Quantitative real-time PCR with the TGP4 primer/probe set provides a sensitive detection and measurement tool to evaluate colonization of sclerotia by Trichoderma spp.     

Moderately virulent African swine fever virus infection: blood cell changes and infective virus distribution among blood components

Blood samples of pigs infected with a moderately virulent African swine fever virus (ASFV) isolate, obtained from the Dominican Republic (DR-II), were monitored temporally for viremia, infective ASFV association with major blood components, differential changes in blood cell composition, and plasma antibodies to ASFV. After intranasal/oral virus inoculation, pigs underwent acute infection and illness that resolved. Acute illness began on postinoculation day (PID) 4 and continued to PID 11, and pigs were febrile, with maximal infective ASFV titers detected in blood. By PID 11, initial antibody titers to ASFV antigens were detected in plasma. The WBC numbers were maintained near preinoculation counts; however, lymphocyte counts decreased slightly with a compensatory increment in neutrophil and monocyte numbers. From PID 11 to PID 25, rectal temperatures gradually returned to preinoculation values, titers of viremia began to decrease, plasma antibody to ASFV antigens increased to peak titers, and WBC numbers increased slightly. Percentages of lymphocytes returned to preinoculation values, neutrophil percentages decreased to slightly below preinoculation values, monocyte percentages were mildly increased, and eosinophil percentages were unaffected. From PID 25 to PID 46, titers of viremia further decreased, and plasma titers of antibodies to ASFV antigens remained high. In pigs with DR-II viremia (PID 4 to PID 46), most viral infectivity (greater than 95%) was RBC associated. Plasma contained less than 1% infectivity, and less than 0.1% of virus was in the WBC fraction (monocytes, lymphocytes, and granulocytes). After PID 46, viremia was no longer detectable.     

Follicular growth and production of estrogen and progesterone after injection of gilts with human chorionic gonadotropin on day 12 of the estrous cycle

Twenty cyclic gilts were injected im with either saline (control) or 1,000 IU of human chorionic gonadotropin (hCG) on d 12 of the estrous cycle to determine the effects of hCG on follicular development and steroidogenesis. Blood was collected when gilts were sacrificed on d 13 or 16. Follicles were classified as medium (3 to 6 mm in diameter) or large (greater than 6 mm diameter), dissected from the ovary, measured and weighed. Pieces of follicle wall were incubated 3 h in Krebs Ringer bicarbonate buffer (KRB) on ice in an atmosphere of air or at 37 C in an atmosphere of 95% O2:5% CO2. Unconjugated estrogen and progesterone in blood plasma, follicular fluid and 10,000 X g supernatants of incubated follicular tissue homogenates were quantified by radioimmunoassay. On d 13 follicles on ovaries of control or hCG-injected gilts were less than or equal to 6 mm in diameter. On d 16, one of five control gilts had some large follicles, while all five hCG-treated gilts had large as well as medium follicles. On d 16 follicular fluid of large follicles from hCG-injected gilts contained twofold more estrogen and 40-fold more progesterone than medium follicles on the same ovaries. Tissue from large follicles of hCG-injected gilts produced more progesterone in vitro than did tissue from medium follicles (P less than .05), but estrogen production did not differ. On d 16 medium follicles from control or hCG-injected gilts were larger, contained more estrogen and less progesterone than those recovered on d 13 (P less than .01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of short-chain fatty acids and lactic acids on survival of Oesophagostomum dentatum in pigs

The direct influence of intracaecal infusion of short-chain fatty acids (SCFA) and lactic acids (LA) on already established Oesophagostomum dentatum infection in cannulated pigs was investigated. We tested the hypothesis that the previously discovered anti-parasitic effect of inulin is mediated through its metabolic products SCFA and LA by infusing into cannulated pigs these compounds in amounts approximating to those produced in the pigs large intestine and caecum during the metabolism of inulin. The experiment comprised of 18 pigs--2 groups of 9 pigs in each. The normal diet used in the experiment was based on barley flour with insoluble fibre from oat husk with added soybean meal, vitamins and minerals. After 2 weeks of adaptation to the diet all the pigs were inoculated with 6,000 infective larvae of O. dentatum. Six weeks later, surgery on all pigs was performed to install cannulas into caeci. At 7 weeks post-infection (p.i.) the SCFA and LA infusion was initiated in Group 1 (experimental) pigs; at the same time pigs in Group 2 (controls) were infused with saline. At week 10 p.i., all pigs were killed and their worm burdens determined. SCFA and LA infused pigs exhibited markedly reduced fecal egg counts and worm recoveries (98 and 92% reduction, respectively, compared to saline controls). The results from this study demonstrate that SCFA and LA have a significant negative influence on established O. dentatum infection in growing pigs. The results also show that the type of dietary carbohydrates fed and its intestinal degradation can yield metabolic by products that profoundly influence helminth survival.     

Expression of tissue factor in canine mammary tumours and correlation with grade,stage and markers of haemostasis and inflammation

Tissue factor (TF) expression in human cancers has been associated with a procoagulant state and facilitation of metastasis. This study was conducted in order to evaluate if TF was expressed in canine mammary tumours. Forty epithelial mammary tumours from 28 dogs were included. TF expression of the tumours was evaluated by immunohistochemistry using a polyclonal antibody against recombinant canine TF. In addition, thromboelastography, haemostatic and inflammatory parameters were evaluated in the patients. TF was recognized in 44% of benign and 58% of malignant tumours. TF localized to the cytoplasmic membrane of neoplastic luminal epithelial cells and/or diffusely in the cytoplasm. No association was found between TF expression and stage or grade of disease. A significant association between TF expression and antithrombin and plasminogen was found, and extensive TF expression was seen in a lymph node metastasis classified as anaplastic mammary carcinoma from a dog with concomitant disseminated intravascular coagulation (DIC).     

Algorithms for sensor-based redistribution of nitrogen fertilizer in winter wheat

Several methods were developed for the redistribution of nitrogen (N) fertilizer within fields with winter wheat (Triticum aestivum L.) based on plant and soil sensors, and topographical information. The methods were based on data from nine field experiments in nine different fields for a 3-year period. Each field was divided into 80 or more subplots fertilized with 60, 120, 180 or 240 kg N ha⁻¹. The relationships between plot yield, N application rate, sensor measurements and the interaction between N application and sensor measurements were investigated. Based on the established relations, several sensor-based methods for within-field redistribution of N were developed. It was shown that plant sensors predicted yield at harvest better than soil sensors and topographical indices. The methods based on plant sensors showed that N fertilizer should be moved from areas with low and high sensor measurements to areas with medium values. The theoretical increase in yield and N uptake, and the reduced variation in grain protein content resulting from the application of the above methods were estimated. However, the estimated increases in crop yield, N-uptake and reduced variation in grain protein content were small.