Effect of dialysis or centrifugation on post-thaw motility and fertility of Santa Gertrudis bull semen collected by electroejaculation

Electroejaculated semen from Santa Gertrudis bulls was used to study the effect of centrifugation (600 x g for 5 min) or dialysis [molecular weight cutoff <14,000 Daltons (Da)] on post-thaw motility and on fertility in beef cattle. Analysis of post-thaw motility showed that the main effects (bulls and semen treatment) were significant (P<0.05). Dialysis significantly improved post-thaw motility in four of seven bulls. Initial volume of seminal plasma in the ejaculate was negatively correlated to post-thaw motility (r = -0.73). No significant improvement in post-thaw motility was observed for bulls with high volumes of ejaculate. In a fertility trial, calving rates of heifers synchronized with PGF(2)alpha and inseminated at 72 and 96 h after the second PGF(2)alpha injection with dialyzed or commercial semen were not statistically different (P>0.05; 54.4% vs 55.4%). These results show that dialysis could be used to improve post-thaw motility of electroejaculated bull semen without altering its fertilizing capacity. However, a high initial volume of seminal plasma seems to have a deleterious effect on sperm freezability that cannot be reversed by dialysis.     

Two-generation reproduction study of di-2-ethylhexyl terephthalate in Crl:CD rats

BACKGROUND: This study was conducted to evaluate the potential adverse effects of di-2-ethylhexyl terephthalate (DEHT) on reproductive capability from exposure of F(0) and F(1) parental animals. METHODS: Four groups of male and female Crl:CD (SD)IGS BR rats (30/gender/group) were exposed to 0, 0.3%, 0.6%, and 1.0% DEHT in the feed for at least 70 consecutive days before mating for the F(0) and F(1) generations. Exposure for the F(0) and F(1) males continued throughout the mating period until euthanasia. Exposure for the F(0) and F(1) females continued throughout mating, gestation, and lactation. The F(1) and F(2) pups were weaned on postnatal day (PND) 21. Assessments included gonadal function, estrous cyclicity, mating behavior, conception rate, gestation, parturition, lactation, and weaning in the F(0) and F(1) generations, and F(1) generation offspring growth and development. RESULTS: DEHT exposure did not affect clinical observations. However, lethality was observed in F(0) and F(1) dams consuming the 1.0% diet during the post-weaning period. No treatment-related mortality occurred in any of the male groups exposed to DEHT or in the female groups exposed to 0.3% or 0.6% DEHT. Male rats consuming the 1.0% diet in both parental generations gained weight more slowly than the controls. There were no indications of adverse effects on reproductive performance in either the F(0) or F(1) generation. Male and female mating and fertility indices, pre-coital intervals, spermatogenic endpoints, reproductive organ weights, lengths of estrous cycle and gestation, live litter size, developmental landmarks, and postnatal survival were similar in all exposure groups. Additionally, ovarian follicle counts for the F(1) females in the high-exposure group were similar to the control values. No adverse exposure-related macroscopic pathology was noted at any exposure level in the F(0) and F(1) generations. CONCLUSIONS: Increases in liver weights were found in the male and female animals exposed to 0.6% or 1.0% DEHT in the diet. Because there were no accompanying histopathologic changes, this effect was not considered adverse. Significant decreases in feed consumption in the female animals from the groups consuming 1.0% DEHT in the diet during lactation accompanied reduced postnatal pup body weights and rate of weight gain. Reductions in pup body weights later in lactation may also have been due to direct consumption of the treated feed by the pups or taste aversion to the same. Reduced relative spleen weight was found in male weanling pups from the 1.0% group in both generations and reduced relative spleen and thymus weights were found in female pups from the 1.0% group in the F(2) generation at necropsy on PND 21. Therefore, for parental and pup systemic toxicity, 0.3% DEHT in the diet (182 mg/kg/day) was considered no-observed-effect level (NOEL). The 1.0% DEHT (614 mg/kg/day) in the diet exposure concentration was considered a NOEL for F(0) and F(1) reproductive toxicity endpoints.     

Cytokine profile of autologous conditioned serum for treatment of osteoarthritis, <Emphasis Type="Italic">in vitro</Emphasis>effects on cartilage metabolism and intra-articular levels after injection

Introduction  

Intraarticular administration of autologous conditioned serum (ACS) recently demonstrated some clinical effectiveness in treatment of osteoarthritis (OA). The current study aims to evaluate the in vitro effects of ACS on cartilage proteoglycan (PG) metabolism, its composition and the effects on synovial fluid (SF) cytokine levels following intraarticular ACS administration.     

The abundance of an invasive freshwater snail Tarebia granifera (Lamarck, 1822) in the Nseleni River,South Africa

The invasive freshwater snail Tarebia granifera (Lamarck, 1822) was first reported in South Africa in 1999 and it has become widespread across the country, with some evidence to suggest that it reduces benthic macroinvertebrate biodiversity. The current study aimed to identify the primary abiotic drivers behind abundance patterns of T. granifera, by comparing the current abundance of the snail in three different regions, and at three depths, of the highly modified Nseleni River in KwaZulu-Natal, South Africa. Tarebia granifera was well established throughout the Nseleni River system, with an overall preference for shallow waters and seasonal temporal patterns of abundance. Although it is uncertain what the ecological impacts of the snail in this system are, its high abundances suggest that it should be controlled where possible and prevented from invading other systems in the region.     

Sensitive fluorescence in situ hybridization signal detection in maize using directly labeled probes produced by high concentration DNA polymerase nick translation

The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.     

Economic evaluation of water loss saving due to the biological control of water hyacinth at New Year’s Dam,Eastern Cape province,South Africa

Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m³ was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biological control. However, at the marginal value product of water, the inclusion of the costs of damage to infrastructure, or the adverse effects of water hyacinth on biodiversity, would justify the use of biological control, even at the low transpiration rate.     

Selected anthropometric variables and aerobic fitness as predictors of cardiovascular disease risk in children

The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children.     

Haplotyping cryptic Adélie penguin taxa using low-cost,high-resolution melt curves

Distinguishing morphologically cryptic taxa, by definition, requires genetic data such as DNA sequences. However, DNA sequences may not be obtained easily for taxa from remote sites. Here we provide the details of a high-resolution melt-curve-based method using taxon-specific primers that can distinguish two taxa of Adélie penguins, and that will be usable in Antarctica when combined with some of the newly developed field-deployable thermal cyclers. We suggest that the wider adoption of field-deployable polymerase-chain-reaction-based techniques will enable faster assignation of haplotype to individuals in situ, and so allow the targeting of observations and sample collection to specimens relevant to the research question. Targeting individuals will also reduce the need to repeatedly handle animals and reduce the time and travel required to complete field work.     

Immunolocalization of MMP-19 in the human intervertebral disc: implications for disc aging and degeneration

Matrix metalloproteinases (MMPs) degrade components of the extracellular matrix of the disc, but the presence of MMP-19 has not been explored. In other tissues, MMP-19 is known to act in proteolysis of the insulin-like growth factor (IGF) binding protein-3, thereby exposing this protein to make it available to influence cell behavior. MMP-19 also has been shown to inhibit capillary-like formation and thus play a role in the avascular nature of the disc. Using immunohistochemistry, normal discs from six subjects aged newborn through 10 years and 20 disc specimens from control donors or surgical patients aged 15-76 (mean age 40.2 years) were examined for immunolocalization of MMP-19; six Thompson grade I discs, five Thompson grade II, eight Thompson grade III, five Thompson grade IV, and one Thompson grade V discs were analyzed. The results indicate that in discs from young subjects, MMP-19 was uniformly localized in the outer annulus. In discs from adult donors and surgical patients, outer and inner annulus cells only occasionally showed MMP-19 localization. The greatest expression of MMP-19 was observed in young discs, and little expression was seen in older or degenerating discs. Because MMP-19 has been shown to regulate IGF-mediated proliferation in other tissues, its decline in the aging/degenerating disc may contribute to the age-related decrease in disc cell numbers.