Culicoides biting midges at the National Zoological Gardens of South Africa

Culicoides biting midges (Diptera: Ceratopogonidae) are responsible for the transmission of a large number of pathogens to livestock and wild animals. In this study the presence of the genus, using light traps based at four different sites within the National Zoological Gardens of South Africa, was investigated during 2002-2004. In total, 37 species were recorded, including large numbers of Culicoides imicola Kieffer, 1913, which is responsible for the transmission of economically important arboviruses in South Africa, Europe, Middle and Far East. These results are discussed with reference to the wider Culicoides fauna in the Onderstepoort area of South Africa, their vector competence as well as biosecurity at the National Zoological Gardens.     

Detection of antibodies to Francisella tularensis in cats

Blood samples were obtained from privately owned cats in Connecticut and New York State, USA in 1985-1990, and analyzed for evidence of Francisella tularensis, the etiologic agent of tularemia. Of the 91 sera tested by microagglutination (MA) methods, 11 (12%) contained antibodies to F. tularensis. Analyses of the same sera by indirect fluorescent antibody (IFA) staining methods revealed 22 (24%) positives. There was good agreement in results of both tests (73% concordance). However, we measured higher titers (1:80 to 1:640) with IFA analysis than by MA methods (1:80 to 1:160). Both tests were suitable for general screening purposes. The DNA of F.tularensis was not detected in the 24 antibody-positive sera tested. Cats living in Connecticut and New York State were naturally exposed to F.tularensis or a closely related organism. With exposure to ticks, other biting arthropods, mice, and rabbits, cats are at risk for acquiring F.tularensis infections and can be an important source of information on the presence of this agent in nature.     

Optimising cutting method and timing for the control of Abutilon theophrasti seed production

Abutilon theophrasti (velvetleaf) is a widespread and problematic annual weed. Greenhouse and field experiments were conducted to investigate the effects of different cutting methods on the viability of A. theophrasti seeds. Three cutting methods were assessed: (1) Entire plant cut and dried (EPD)—plants were cut at soil level and dried with capsules attached on the greenhouse bench or soil surface for 4 weeks; (2) capsules detached and dried (CD)—capsules were removed from plants and dried for 4 weeks; and (3) capsules detached and tested while fresh (CF)—a control treatment. Before drying, the developmental stage (stage one, dark green; stage two, light green; stage three, yellowish-green; or stage four, black with the slightly open capsule) and age (days after flowering, DAF) of each capsule was recorded. Seed viability was measured immediately in the CF treatment and after the 4-week drying period in the EPD and CD treatments. No seeds in the EPD and CD treatments were viable when harvested at the first developmental stage (1–8 DAF) in either experiment, but 100% of seeds in the CF treatment in the field were viable when harvested at 8 DAF. In both greenhouse and field experiments, seeds attained full viability at earlier harvest ages in CF than in EPD or CD treatments, suggesting that seeds might become viable relatively early in development but lose viability if allowed to dry. These findings could be applied to optimise late-season mechanical control of A. theophrasti.     

Role of social structure in establishment of an invasive large mammal after translocation

Background

Data on the movement behavior of translocated wild pigs is needed to develop appropriate response strategies for containing and eliminating new source populations following translocation events. We conducted experimental trials to compare the home range establishment and space-use metrics, including the number of days and distance traveled before becoming range residents, for wild pigs translocated with their social group and individually.

Results

We found wild pigs translocated with their social group made less extensive movements away from the release location and established a stable home range ~5 days faster than those translocated individually. We also examined how habitat quality impacted the home range sizes of translocated wild pigs and found wild pigs maintained larger ranges in areas with higher proportion of low-quality habitat.

Conclusion

Collectively, our findings suggest translocations of invasive wild pigs have a greater probability of establishing a viable population near the release site when habitat quality is high and when released with members of their social unit compared to individuals moved independent of their social group or to low-quality habitat. However, all wild pigs translocated in our study made extensive movements from their release location, highlighting the potential for single translocation events of either individuals or groups to have far-reaching consequences within a much broader landscape beyond the location where they are released. These results highlight the challenges associated with containing populations in areas where illegal introduction of wild pigs occurs, and the need for rapid response once releases are identified. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Are microconidia infectious principles in Neonectria ditissima?

Journal of Plant Diseases and Protection - Comparative studies of different isolates of Neonectria ditissima obtained from canker lesions and rotten fruit showed that both five-septate macroconidia...     

Unraveling the morphological patterns of a subantarctic eelpout: a geometric morphometric approach

Phenotypic variation in organisms depends on the genotype and the environmental constraints of the habitat that they exploit. Therefore, for marine species inhabiting contrasting aquatic conditions, it is expected to find covariation between the shape and its spatial distribution. We studied the morphology of the head and cephalic sensory canals of the eelpout Austrolycus depressiceps (4.5–22.5 cm TL) across its latitudinal distribution in South Pacific (45°S–55°S). Geometric morphometric analyses show that the shape varied from individuals with larger snout and an extended suborbital canal to individuals with shorter snouts and frontally compressed suborbital canal. There was size variation across the sampled populations, but that size does not have a clear latitudinal gradient. Only 8% of the shape variation relates to this size variation (allometry), represented by a decrease in the relative size of the eye, and a depression of the posterior margin of the head. There were spatial differences in the shape of the head, but these differences were probably caused by allometric effects. Additionally, 2 of the canals of the cephalic lateralis pores and the head shape showed modularity in its development. This study shows that the morphology of marine fish with a shallow distribution varies across distances of hundreds of kilometers (i.e., phenotypic modulation).     

苏氨酸和异亮氨酸对皖西白鹅屠宰性能、器官指数及肠道形态结构、消化酶活性、抗氧化和免疫指标的影响

本试验旨在研究苏氨酸和异亮氨酸对皖西白鹅屠宰性能、器官指数及肠道形态结构、消化酶活性、抗氧化和免疫指标的影响。选取30日龄体重相近的皖西白鹅180只,随机分为3组,每组3个重复,每个重复20只。对照组饲喂基础饲粮,苏氨酸组在基础饲粮中添加2.0 g/kg的L-苏氨酸,异亮氨酸组在基础饲粮中添加2.5 g/kg的L-异亮氨酸。试验期60 d。结果表明：1）各组之间90日龄屠宰性能和器官指数无显著差异（P>0.05）。2）异亮氨酸组60日龄十二指肠和空肠绒毛高度、隐窝深度显著或极显著高于对照组（P<0.05或P<0.01）,苏氨酸组60日龄十二指肠、空肠和回肠隐窝深度及90日龄十二指肠和回肠绒毛高度显著或极显著高于对照组（P<0.05或P<0.01）。3）苏氨酸组和异亮氨酸组60、90日龄十二指肠胰蛋白酶活性极显著高于对照组（P<0.01）,苏氨酸组60、90日龄十二指肠麦芽糖酶活性及90日龄空肠淀粉酶、乳糖酶活性显著或极显著高于对照组（P<0.05或P<0.01）。4）异亮氨酸组60日龄空肠总抗氧化能力显著高于对照组和苏氨酸组（P<0...     

Pilot study of the ultrasonographic examination of the intact and transected medial glenohumeral ligament in dogs

Medial glenohumeral ligament injury is commonly reported during medial shoulder joint instability in dogs. Arthroscopy is considered the gold standard procedure, but it is invasive and requires distension of the joint. Ultrasonographic examination of the medial glenohumeral ligament has been studied as a possible, less invasive alternative to arthroscopy however it has not been considered a useful method of assessment due to the interference of the probe with the pectoral muscles. The aims of this prospective analytical randomized pilot study were to develop a standardized ultrasound protocol for visualizing the canine medial glenohumeral ligament and to compare goniometry and ultrasound findings in cadaver dogs with versus without transection of the medial glenohumeral ligament. Nine adult Beagle cadavers (18 shoulders) were used. The first six shoulders were used in a preliminary study to describe an ultrasound technique to identify the medial glenohumeral ligament. Arthroscopy was performed on the remaining 12 shoulders, with six randomly selected medial glenohumeral ligaments from these shoulders, transected during the procedure. Ultrasound examination was performed after each arthroscopic procedure by an ultrasonographer blinded to the patient group. Four medial glenohumeral ligaments (67%) were correctly identified during the preliminary study. Ultrasonographic examination failed to diagnose the transection of all six medial glenohumeral ligaments in the second part of the study. No difference was observed in the ligament thickness between the dogs with and without a transected medial glenohumeral ligament. Dogs with a transected medial glenohumeral ligament had a wider articular space compared to dogs without a transected ligament (P < 0.001), and an articular space wider than 8.2 mm was discriminatory of a transected medial glenohumeral ligament in all the shoulders. In conclusion, the medial glenohumeral ligament could be identified with a medial ultrasonographic approach of the shoulder and a wider articular space can be a sign of a medial shoulder joint instability. Further studies are needed to confirm these preliminary findings in living dogs, with and without shoulder instability.     

Intra- and interobserver assessments of intestinal wall thickness and segmentations from transverse sections of feline abdominal ultrasound images

Measurements of intestinal wall thicknesses from ultrasound imaging (US) are routinely used to support diagnoses of intestinal disorders in cats, however published studies describing observer agreement are currently lacking. The aim of this retrospective, observer agreement study was to quantify inter- and intraobserver repeatability and agreement in the measurement of intestinal wall layer thicknesses and the segmentation of transverse sections of small intestines in US images of 20 cats. Intestinal wall layer thickness measurements of the mucosa, submucosa, muscularis, serosa layer, and total thickness of these layers were performed on five cats with small cell epitheliotropic lymphoma, five with inflammatory bowel disease, and 10 with other conditions. Thickness measurements and the segmentation encompassing the serosa layer were obtained from five observers four times non-sequentially. The average standard deviation in thickness measurements (95% confidence interval) in the mucosa, submucosa, muscularis, serosa, and total thickness were 0.35 (0.07–0.95), 0.24 (0.07-0.52), 0.22 (0.06-0.49), 0.20 (0.05-0.49), and 0.57 (0.11-1.60) mm, respectively. The average intraclass correlation coefficients, which estimates the degree of consistency in thickness measurements and segmentation areas for each observer, ranged from 0.355 to 0.870 and 0.850 to 0.993, respectively. The interclass correlation coefficient, which estimates the degree of consistency when measuring a thickness or segmentation area over all observers ranged from 0.115 to 0.753, and 0.811 to 0.902, respectively. The overall average Dice Coefficient, which estimates the extent of overlap of the segmentations for all observers was 0.957 (0.933 to 0.972). Our results suggest segmentations of small intestines have a higher interobserver agreement than measurements of intestinal wall thicknesses.