Prevalence of odontoclastic resorptive lesions in a population of clinically healthy cats

The prevalence of odontoclastic resorptive lesions (ORLs) was determined in a clinically healthy cat population (228 cats) using both clinical (oral examination) and radiographic (full-mouth series with intraorally positioned dental film) methods. The overall prevalence rate was 29 per cent (mean age of the cat population 4.9 years). The mandibular third premolars (307, 407) were the most commonly affected tooth and the pattern of ORL development was symmetrical in most cats. The risk of having ORLs was found to increase with increasing age and cats with clinically and radiographically missing teeth were more likely to have the condition. Neutering, gender, age at neutering or mean whole mouth gingivitis index did not affect the prevalence of ORLs.     

Effect of long-term intermittent periodontal care on canine periodontal disease

The periodontal health status was assessed in two groups of dogs which had received different levels of periodontal care over a two-year period. The dental group received regular dental scaling and polishing, and intermittent daily tooth brushing, while the control group received no periodontal care. All dogs developed gingivitis, and two (one from each group) showed evidence of incipient periodontitis. The dental group had a reduced gingivitis index (GI) compared with the control group only when they had received daily tooth brushing before the GI assessment. When the dogs had not had their teeth brushed for four weeks before the assessment, the GI was not significantly different to that in the control dogs. This suggests that continual periodontal care throughout life is of great importance and questions the benefits of intermittent oral care. The GI of the palatal and lingual surfaces in all dogs was significantly higher than the GI of the buccal surfaces. Thus, all tooth surfaces may need to be cleaned to achieve optimal periodontal health.     

Effect of a dental chew on dental substrates and gingivitis in cats

The use of special diets or dietary adjuncts, although not eliminating the need for regular professional therapy, may serve to improve gingival health during the interval between professional oral health assessments and intervention. This study was performed to determine the effect of a dental chew on dental hygiene and gingival health in cats. The accumulation of dental substrates and the development of gingivitis were assessed in cats fed either a dry diet only or a dry diet supplemented with dental chews. A two-period, crossover design was used with the test phase lasting 4-weeks. Results indicated that the daily addition of dental chews to a dry diet was effective in reducing plaque and calculus accumulation on tooth surfaces in cats, as well as reducing the severity of gingivitis.     

The Effect of Season on Spermatozoa Motility,Plasma Membrane and Acrosome Integrity in Fresh and Frozen–Thawed Semen from Xinong Saanen Bucks

The aim of this study was to evaluate whether the season of ejaculate collection influences seminal quality parameters of pre‐ and post‐freeze–thawing in Xinong Saanen bucks. Ejaculates were collected from eight bucks throughout the four seasons (spring, summer, autumn and winter) in a 12 months’ time period, identified in the Northern Hemisphere. Semen samples were evaluated by the combinations of conventional and Computer‐Assisted Sperm Analysis (CASA) when fresh and after frozen–thawed, respectively. The results clearly demonstrated that season of ejaculate collection influenced (p < 0.05) fresh semen quality. Highest semen quality was observed during autumn. On the contrary, undesirable indices (significantly lower, p < 0.05) were observed in winter as compared with the other remaining seasons. CASA has clearly shown the influences of seasonal variations on semen motility parameters. Furthermore, season of ejaculate collection was also found to influence sperm freezability. Semen characteristics after frozen–thawed followed a similar pattern with that of fresh ejaculate except in spring. The results revealed that sperm quality was higher (p < 0.01) in summer and autumn than in spring and winter. In conclusion, seasonal variation influences semen quality in Xinong Saanen bucks. In addition to summer and autumn, fresh ejaculates in spring can also be successfully used for AI. Sperm from ejaculates collected during summer and autumn are more suitable for cryopreservation. Hence, it is possible to increase the efficiency of goat breeding by manipulating the seasonal variations of semen quality for immediate AI and/or cryopreservation.     

Review of the effects of 12 selected biocides on target and non-target soil organisms

This literature review investigates biocides that claim to reduce the populations of specific target groups, i.e. bacteria, saprophytic fungi, vesicular-arbuscular mycorrhizae, protozoa, nematodes, or soil-dwelling microarthropods. Removal or reduction of organism groups in natural ecosystems would allow study of their functional role in non-laboratory situations. The biocides considered in this review are those which are supposed to have a ‘narrow spectrum’ (affect only one group), and can be applied as a solution or suspension to the soil. The effects of aldrin, benomyl, captan, carbofuran, chloroneb, cycloheximide, diazinon, oxytetracycline, parachloronitrobenzene (PCNB), streptomycin, thiabendazole, and thiram on both target and non-target soil organisms are summarized. Each soil organism group except protozoa was reduced by at least one biocide, and usually by several biocides. Of the biocides reviewed, none had effects which were strictly limited to their target group and all have been reported to reduce more than one group of organisms. The responses of soil organisms to these biocides are tabulated.     

Retinoic acid signaling restricts the cardiac progenitor pool

Organogenesis begins with specification of a progenitor cell population, the size of which provides a foundation for the organ's final dimensions. Here, we present a new mechanism for regulating the number of progenitor cells by limiting their density within a competent region. We demonstrate that retinoic acid signaling restricts cardiac specification in the zebrafish embryo. Reduction of retinoic acid signaling causes formation of an excess of cardiomyocytes, via fate transformations that increase cardiac progenitor density within a multipotential zone. Thus, retinoic acid signaling creates a balance between cardiac and noncardiac identities, thereby refining the dimensions of the cardiac progenitor pool.     

RADIOGRAPHIC CHANGES IN TESTES OF BULLS INFECTED WITH BESNOITIOSIS

Ten beef bulls infected with Besnoitiosis were examined radiographically and pathologically. Eight of these were slaughtered soon after diagnosis; two were left for a six-month observation period. The radiographic findings were focal and branching-tree calcification of the testes. Histopathologic examination proved these calcifications to be necrotic sections of the seminiferous tubules. Radiography of the testes as a means of evaluating the fertility status of the infected bull is recommended.     

The Relationship Between Post‐Thaw Sperm DNA Integrity and Non‐Return Rate Among Norwegian Cross‐Bred Rams

With the aim of investigating the relationship between sperm DNA integrity and non‐return rate (NRR) among Norwegian cross‐bred rams, semen from 15 individuals was examined by flow cytometry. Sperm Chromatin Structure Assay (SCSA) quantifies the proportion of spermatozoa with denatured DNA after in situ acid treatment, and the four parameters % DFI, % HDS, MEAN DFI and SD DFI are all different measures of DNA denaturation and maturation. Field fertility, reported as NRR 25 days after insemination was based on all inseminations from a large‐scale breeding programme and supplied by the Norwegian Association of Sheep and Goat Farmers. From each ram, four straws from four different weeks of the breeding season were analysed, and the associations between 25‐day NRR and the mean of the four SCSA parameters were tested using a logistic regression model. The results revealed no association between fertility and % DFI or % HDS, while SD DFI and MEAN DFI showed a significant negative association with NRR. Further, the SCSA values varied significantly between ejaculates within ram among some of the rams in the study. However, no significant association was seen between these intra‐individual differences in sperm DNA integrity and NRR. In conclusion, this study suggests an association between sperm DNA integrity and NRR for rams. However, further research must be conducted to confirm these findings and determine whether sperm DNA assessments can be applied to predict ram fertility.