Radiation safety practices among Canadian equine veterinary workers during diagnostic procedures with portable X-ray equipment

The objective of this study was to report observed radiation safety practices among equine workers using portable X-ray units at 3 veterinary practices in Canada. Practice 1 was comprised of equine field service workers from an academic institution, whereas Practices 2 and 3 were comprised of workers from private equine referral practices. Out of 2969 exposure-worker observations, protective aprons were worn for > 99% (2968/2969), thyroid shields for 87% (2584/2969), and eyeglasses for 10% (310/2969). The cassette was held by hand for 97% (1078/1114) of observations, and the X-ray unit was held by hand for 100% (1293/1293) of observations. Gloves were used for 54% (606/1114) and < 1% (5/1293) of observations involving cassette holders and X-ray tube operators, respectively. Use of gloves was more frequent among technologists than DVMs (P = 0.004), and among workers in Practices 1 and 3 than in Practice 2 (P < 0.001). In conclusion, given that workers commonly hold cassettes and X-ray tubes by hand, improvement in shielding use is needed. Consideration should be given to specific behavior recommendations in radiation regulations.     

Associations between deprivation, attitudes towards eating breakfast and breakfast eating behaviours in 9-11-year-olds

OBJECTIVES: To examine school-level relationships between deprivation and breakfast eating behaviours (breakfast skipping and the healthfulness of foods consumed) in 9-11-year-old schoolchildren and to examine whether attitudes towards eating breakfast mediated these relationships. DESIGN: Cross-sectional survey. SETTING: One hundred and eleven primary schools in Wales. SUBJECTS: Year 5 and 6 pupils within the 111 primary schools. Measures were completed by 4314 children. Analysis was conducted at the group (school) level, with each school representing one group. RESULTS: Deprivation was positively associated with breakfast skipping and consumption of 'unhealthy' items (i.e. sweet snacks, crisps) for breakfast. A significant negative association was found between deprivation and consumption of 'healthy' items (i.e. fruit, bread, cereal, milk). Deprivation was significantly inversely associated with attitudes towards eating breakfast. The relationships between deprivation and (1) breakfast skipping and (2) consumption of 'healthy' items for breakfast were mediated by attitudes towards eating breakfast. The hypothesis that attitudes mediated the relationship between deprivation and consumption of 'unhealthy' breakfast items was unsupported. CONCLUSIONS: Deprivation is associated with adverse breakfast eating behaviours amongst children aged 9-11 years, in terms of breakfast skipping and the quality of breakfasts consumed. Socio-economic differences in attitudes towards eating breakfast are apparent amongst this age group, and appear to relate to social gradients in breakfast eating behaviours. Research is needed to examine the causal nature of these trends and to elucidate factors underlying the development of socio-economic differences in eating-related cognitions.     

Greenlip abalone (Haliotis laevigata Donovan, 1808) sperm cryopreservation using a programmable freezing technique and testing the addition of amino acid and vitamin

This study investigated factors key to the development of sperm cryopreservation in the greenlip abalone Haliotis laevigata using a programmable freezing technique, including (1) permeable cryoprotectant agent (CPA) selection; (2) cooling rate; (3) endpoint temperature; (4) thawing temperature; (5) sperm to egg ratio and (6) sugar, vitamin and amino acid supplementation, using sperm motility, fertilization rate, plasma membrane integrity, mitochondrial membrane potential or acrosome integrity as quality assessment indicators. Results showed that among the permeable CPAs evaluated, 10% dimethyl sulfoxide was the most suitable for greenlip abalone sperm cryopreservation. The highest post‐thaw sperm motility was achieved with the sperm being frozen at a cooling rate of ?5°C min^?1 to ?30°C from 0°C and thawed and recovered in 40°C and 18°C seawater baths respectively. The addition of sugars in 10% dimethyl sulfoxide did not significantly improve the post‐thaw sperm motility and fertilization rate. The addition of 0.6% glycine, 0.2% taurine or 0.02% L‐ascorbic acid, on the other hand, significantly improved the post‐thaw sperm motility. However, only the addition of 0.6% glycine improved the post‐thaw sperm fertilization rate, which was further confirmed by the improvement of the post‐thaw sperm mitochondrial membrane potential and acrosome integrity through flow cytometry analysis.     

Corpus Luteum–Endometrium–Embryo Interactions in the Dairy Cow: Underlying Mechanisms and Clinical Relevance

Conception rates of dairy cows are currently declining at an estimated 1% every year. Approximately, 35% of embryos fail to prevent luteolysis during the first three weeks of gestation. Interactions between the corpus luteum, endometrium and embryo are critical to the successful establishment of pregnancy and inadequacies will result in the mortality of the embryo. For example, as little as a one day delay in the post-ovulatory rise of progesterone has serious consequences for embryo development and survival. Recently, we found that LH support, degree of vascularization and luteal cell steroidogenic capacity were not the major factors responsible for this luteal inadequacy, but are nevertheless essential for luteal development and function. Progesterone acting on its receptor in the endometrium stimulates the production of endometrial secretions on which the free-living embryo is dependent. However, their exact composition and effects of inadequate progesterone remains to be determined. The embryo is recognized through its secretion of interferon tau (IFNT), which suppresses luteolytic pulses of prostaglandin F_2α. In the cow, it is most likely that IFNT inhibits oxytocin receptor up-regulation directly and does not require the prior inhibition of oestrogen receptor α (ESR1). Unravelling the precise luteal-endometrium and embryo interactions is essential for us to understand pregnancy establishment and development of strategies to reverse the declining fertility of dairy cows.     

Identification of elevated concentrations of estradiol in bovine uterine endometrium

We have investigated the estradiol content of bovine endometrium and related this to circulating plasma estradiol content. In 9 heifers, mean ± S.E.M. plasma estradiol concentration was 0.64 ± 0.25 pg/ml while the mean ± S.E.M. endometrial estradiol content was 43.0 ± 14.7 pg/g tissue; there was a close relationship between plasma and tissue estradiol levels (R² = 0.81; P < 0.001). During culture of endometrial tissue there was a progressive transfer of estradiol from tissue to culture media but no change in total estradiol. Culture of endometrium from 4 heifers with 5 ng/ml testosterone for 72 h resulted in no increase in estradiol. Furthermore, immunohistochemistry revealed no aromatase protein in uterine endometrium. These results confirm high stored tissue concentrations of estradiol in bovine endometrium while providing no evidence for estradiol synthesis by this tissue. The mechanism(s) through which this sequestration of estradiol into uterine tissue occurs remains to be determined.     

Morphological and phenological variation in the wild relatives of lentil

Wild lentils are a potentially important source of genetic variation for the improvement of the cultivated lentil. A lack of evaluation data for characters of economic importance is one constraint to their use in breeding programmes. Here, variation in selected phenological and agro-morphological characters in 310 accessions of wild lentils is reported. This includes 153 accessions of Lens culinaris subsp. orientalis, 33 accessions of L. odemensis, 32 accessions of L. nigricans, 90 accessions of L. ervoides and 2 accessions of L. lamottei. Certain L. culinaris subsp. orientalis accessions had substantially more leaves per plant, peduncles per plant, pods per plant and seeds per plant, and greater leaf area than two cultivated lentil checks. The total biomass obtained from the best L. culinaris subsp. orientalis accessions was comparable with the checks. The harvest index of one check was comparable with that of the two best L. culinaris subsp. orientalis accessions. Of the wild taxa, the L. lamottei had the highest average 100-seed weight. Broad-sense heritabilities were calculated and found to be high for days to average flowering and days to average podding. Significant correlations exist between quantitative characters and latitude of origin. Phenological adaptation, through sensitivity to photoperiod, temperature or both, appear to be a major evolutionary force in wild lentils. Variation is mapped according to geographical origin of accessions in order to identify geographical patterns or clines of variation. Accessions of L. culinaris subsp. orientalis from Uzbekistan, Turkmenistan and Tajikistan had among the largest biomass, the most peduncles per plant and many pods and seeds per plant. One-hundred seed weight, however, did not decline as expected with increased seed number.     

中美牧草种质资源联合评价试验网中国试验区试验报告

在中国内蒙古高原中西部地区和美国西部落基山区建立亚洲及北美牧草资源评价试验网,对选自中美双方的禾本科,豆科牧草和灌木进行为期４－７年的联合评价。中国试验区试验结果指出,产于中国的冰草属牧草,豆科小半灌木和草本植物在典型昌原和荒漠草原的建标量率和生物产量显著优于引自北美的草种。中国的羊草和北美的牧冰草在典型草原的适应性相近,但羊草的牧草稳产性显著优于北美牧冰草。美国的耐盐、挞盐禾草在内蒙古黄河灌溉区     

Laser vocal cordectomy fails to effectively reduce respiratory noise in horses with laryngeal hemiplegia

OBJECTIVE: To report the effect of unilateral laser vocal cordectomy on respiratory noise and airway function in horses with experimentally induced laryngeal hemiplegia (LH). STUDY DESIGN: Experimental study. ANIMALS: Six Standardbred horses without upper airway abnormalities at rest or during high-speed treadmill exercise. METHODS: Respiratory sounds and inspiratory trans-upper airway pressure (P(Ui)) were measured before (baseline) and 14 days after induction of LH by left recurrent laryngeal neurectomy, and again 30, 60, 90, and 120 days after endoscopically assisted laser cordectomy of the left vocal cord. Data were collected with the horses exercising on a treadmill at a speed producing maximum heart rate (HR(max)). RESULTS: In horses exercising at HR(max), induction of LH caused a significant increase in P(Ui), sound level (SL), and the sound intensity of formant 2 (F(2)) and 3 (F(3)). The sound intensity of formant 1 (F(1)) was unaffected by induction of LH. Laser vocal cordectomy had no effect on SL, or on the sound intensity of F(1) and F(3). At 30, 60, 90, and 120 days after surgery, P(Ui) and the sound intensity of F(2) were significantly reduced, but these variables remained significantly different from baseline values. CONCLUSIONS: Unilateral laser vocal cordectomy did not effectively improve upper airway noise in horses with LH. The procedure decreased upper airway obstruction to the same degree as bilateral ventriculocordectomy. CLINICAL RELEVANCE: Currently, laser vocal cordectomy cannot be recommended for the treatment of upper airway noise in horses with LH.