Retinal degeneration in nine Swedish Jämthund dogs

The Jämthund is the fourth most common breed in Sweden with approximately 1600 pups registered each year. Although it has been known that some adult dogs go blind, so they cannot hunt, the Jämthund dog has historically not been screened for hereditary eye diseases. This report describes nine Swedish Jämthund dogs with retinal degeneration. These dogs represent all Jämthund dogs diagnosed with progressive retinal atrophy (PRA) by the Swedish Eye Panel and registered with the Swedish Kennel Club from January 1998 to September 2008. The dogs were examined with indirect opthalmoscopy and slitlamp biomicroscopy. Additionally, electroretinograms (ERGs) following ECVO guidelines were performed in two dogs (one affected and one normal) and the eyes from three affected dogs were examined by light‐microscopy postmortem. Typical findings were bilateral symmetric generalized retinal degeneration with tapetal hyper‐reflectivity, attenuation of blood vessels and pigment clumping in the nontapetal fundus. These retinal findings progressed with time in two dogs after re‐examination. Visual impairment, especially under dim light conditions, was observed in the affected dogs. ERG from one affected dog showed profoundly reduced rod responses, whereas cone responses were better preserved. Microscopic changes in the eyes from three dogs were characterized by a severe diffuse predominantly outer retinal degeneration and atrophy. Re‐sequencing of the prcd‐gene for eight of the nine investigated dogs revealed that none of the individuals carried disease allele that has been associated with prcd‐PRA in other breeds. In conclusion, ophthalmoscopic, electroretinographic, and light‐microscopic alterations observed in nine Jämthund dogs were compatible with PRA. The prcd mutation was excluded as a cause of this retinopathy.     

Changes in follicular vascularity during the first follicular wave in lactating cows

Increase in the blood supply to individual follicles appears to be associated with follicular growth rates and the ability to become the dominant follicle, while reduced thecal vascularity appears to be closely associated with follicular atresia. Therefore, this study aimed to determine the real-time changes in the vascularity of the follicle wall during the first follicular wave in cycling Holstein cows. Normally cycling and lactating cows (n=5) were examined by transrectal color Doppler ultrasonography (the sensitivity for velocity: > 2 mm/sec) to determine the changes in the vasculature of the follicle wall (presence or absence of blood flow) and the diameter of follicles. A new follicular wave and ovulation were induced by GnRH injection at 48 h after an injection of PGF2alpha analogue. The ovaries were scanned daily for 7 days after GnRH injection. Follicles >2.5 mm were classified into 3 groups by the changes in diameter as follows: 1) largest follicle, 2) second largest follicle, and 3) small follicles, which included all other follicles >2.5 mm. Before the follicle selection, there was no significant difference in the percentage of follicles with detectable blood flow between the subsequently determined largest and second largest follicles. After the follicle selection, the percentage of follicles with detectable blood flow significantly decreased among the second largest follicles. In addition, small follicles with detectable blood flow kept larger diameters than those without detectable blood flow from one day before the occurrence of follicle selection. It is likely that maintenance of follicle vasculature and appropriate blood supply to the larger follicles is essential for follicle dominance. In small follicles, the presence of blood flow within the wall also appears to be required for recruitment. Consequently, the data suggest that the change of the blood supply to an individual follicle closely relates to the dynamics of follicular growth in the first follicular wave in the cow.     

Effects of LH and PGF2alpha in equine dominant follicles observed by MDS

Microdialysis System (MDS) is a novel technique used for investigation of molecule secretion between different cell populations. Local hormonal secretion at follicular wall has been still unclear. This MDS study was used to determine progesterone (P4), androstenedione (A4), estradiol-17beta (E2) and Prostaglandin F2alpha (PGF2alpha) release in mare pre-ovulatory follicles. Follicles larger than 30 mm were isolated from the ovary and follicular fluid aspirated for hormone assay. Follicular fluid collected from small, middle and large follicles were analyzed by EIA. The concentrations of P4 and PGF2alpha were similar among the different sizes of follicles. The release of A4 was observed in middle and large follicles. E2 concentration was observed in middle follicles and was higher in large follicles compared with middle follicles. Follicular wall was cut and incubated for MDS and when LH was infused, there was an increase in P4 and A4 release. PGF2alpha release was considerably high after LH infusion compared to the control group. Infusion of PGF2alpha increased P4 and A4 release but there was no change in E2 release. This results suggest that in pre-ovulatory follicles, LH stimulates theca interna cells and also PGF2alpha seemed to have a mediator role to induce steroid hormone production and luteinization of follicular cells. The nature of the mechanisms involved in selection of large follicles is still a perplexing research problem in reproduction.     

智利猕猴桃产业概况

2006年12月,在国家外专局出国项目的支持下,我们一行4人,对智利猕猴桃生产进行了为期一个月的考察学习,现就智利猕猴桃产业发展情况谈谈我们的所得.     

Pediatric abdominal ultrasonography.

Pediatric patients are commonly presented to the veterinarian because of signs referable to the abdominal cavity caused by congenital anomalies,dietary indiscretion, parasitic infestation, and infectious disease. Abdominal ultrasound provides valuable clinical information about the peritoneal cavity, great vessels, abdominal viscera, and lymph nodes,which is obtained in a noninvasive fashion and usually does not necessitate sedation or anesthesia. Ultrasonography thus greatly facilitates diagnostic evaluation of the pediatric patient. Ultrasound equipment already in place in many small animal veterinary clinics is appropriate for most pediatric cases.     

Effects of prostaglandin F(2alpha) and nitric oxide on the secretory function of bovine luteal cells

The objective of the present study was to investigate the influence of prostaglandin F(2alpha) (PGF (2alpha)) and nitric oxide (NO) on production of steroids and PGs by culturing bovine luteal cells obtained from ovaries on days 8-12 of the estrous cycle with a nitric oxide (NO) donor (Spermine NONOate), and a NO synthase inhibitor (N(G)-nitro-L-arginine methyl ester dihydrochloride: L-NAME). When the cells were exposed for 24 h to PGF(2alpha) (10(-7)-10(-5) M), production of progesterone (P(4)) increased significantly at all doses used (P<0.05). Moreover, PGF(2alpha) stimulated PGF(2alpha) production (P<0.01), depressed testosterone (T) production (P<0.05), but did not affect synthesis of prostaglandin E(2) (PGE(2)). Spermine NONOate decreased P(4) production to 66%, 47% and 34% of the control concentration after treatment with 10(-5) M, 10(-4) M and 10(-3) M, respectively, but did not affect T production, and increased PGF(2alpha) synthesis (P<0.05) and PGE(2) (P<0.01) at all doses used. L-NAME increased production of P(4) (P<0.01) but did not affect (P>0.05) secretion of T, PGF(2alpha) and PGE(2). Estradiol-17beta (E(2)) was detectable on the level of sensitivity of assay and was not significantly altered by any treatments. The overall results suggest that PGF(2alpha) and NO produced locally in bovine CL play roles in the regulation of the secretory function of the bovine CL as auto/paracrine factors.     

Biofilm development in micro-irrigation emitters for wastewater reuse

Laboratory experiments were carried out to investigate bioclogging on three types of online emitters using synthetic wastewater filtered at 10 μm (COD = 200 mg L^?1). The three types of emitters were as follows: non-pressure-compensating emitters delivering 2 L h^?1 (NPC2), non-pressure-compensating emitters delivering 4 L h^?1 (NPC4) and pressure-compensating emitters delivering 2.2 L h^?1 (PC). They were plugged on two parallel pipe diameters (16 and 20 mm). Emitter performance was followed by flow rate measurements. The results showed that PC emitters seemed to be more sensitive to clogging than NPC emitters. Biofilm was observed mainly on NPC flow paths and PC membranes; its presence was also confirmed by the assessment of different water quality parameters such as total organic carbon and pH. Experimental results compared with a model designed with computational fluid dynamics Software (ANSYS Fluent^®) showed relations between biofilm development and velocity distribution on NPC flow paths. Finally, pipe diameter also appeared to be a parameter inducing emitter clogging.     

IPM Strategies and Their Dilemmas Including an Introduction to www. eurowheat.org

Information about disease management in winter wheat （Triticum aestiva） in eight European countries was collated and analysed by scientists and extension workers within the European Network for the Durable Exploitation of Crop Protection Strategies （ENDURE）. This included information about specific disease thresholds, decision support systems, host varieties, disease prevalence and pathogen virulence. Major differences in disease prevalence and economic importance were observed. Septoria tritici blotch （Mycosphaerella graminicola） was recognized as the most yield reducing disease in countries with intensive wheat production, but also rust diseases （Puccinia striiformis and Puccinia triticina）, powdery mildew （Blumeria graminis） and Fusarium head blight （Fusarium spp.） were seen as serious disease problems. Examples of current integrated pest management （IPM） strategies in different countries have been reported. Disease management and fungicide use patterns showed major differences, with an average input equivalent to 2.3 full dose rates （TFI） in the UK and a TFI of 0.6 in Denmark. These differences are most likely due to a combination of different cropping systems, climatic differences, disease prevalence, and socio-economic factors. The web based information platform www.eurowheat.org was used for dissemination of information and results including information on control thresholds, cultural practices which can influence disease attack, fungicide efficacy, fungicide resistance, and pathogen virulence, which are all elements supporting 1PM for disease control in wheat. The platform is open to all users. The target groups of EuroWheat information are researchers, advisors, breeders, and similar partners dealing with disease management in wheat.