Comparison of bacterial organisms and their susceptibility patterns from otic exudate and ear tissue from the vertical ear canal of dogs undergoing a total ear canal ablation

The purpose of this prospective study was to compare bacterial organisms and their susceptibility patterns from otic exudate and ear tissue from the vertical ear canal of six dogs with end-stage otitis undergoing a total ear canal ablation. Twenty-six organisms, 13 from the exudate and 13 from the tissue, were morphologically and biochemically similar, and their susceptibility patterns were compared. There were discrepancies for only 5 antibiotics for 4 organisms from 3 dogs. Culture of otic exudate from the vertical ear canal of dogs with chronic end-stage otitis externa provides an accurate reflection of the bacterial species present and the antimicrobial susceptibility patterns of these infections.     

Microspatial genetic diversity of Dothistroma septosporum

The distribution of genetic diversity in a local population of Dothistroma septosporum was determined on a microspatial geographical scale. The study was conducted in a seed orchard of Pinus nigra divided into four plots, each of 0.84 ha in area. Ninety‐two isolates were obtained from needles with red band needle blight symptoms. Molecular variance, Mantel test and autocorrelation spatial analyses were performed with the use of random amplified microsatellites markers to test the null hypothesis of a random distribution of genotypes. The groups of isolates from individual plots demonstrated small differences as regards intrapopulation variation. The mean contribution of polymorphic loci for isolate groups was almost 77%, genetic diversity 0.270, while the Shannon coefficient was 0.389. The Mantel test demonstrated a significant, positive correlation between Huff's genetic distance and geographical distance. Significant spatial genetic structure was detected with autocorrelation coefficients being significant in the first two distance classes up to about 8–12 m.     

The effect of a seaweed concentrate on the in vitro growth and acclimatization of potato plantlets

Summary The seaweed concentrate ‘Kelpak’ is used commercially in the greenhouse and field to improve plant quality. ‘Kelpak’ was added to the in vitro culture medium of potato cv. ‘BP1’ and also applied as a leaf/soil drench immediately after transplanting. The addition of 0.25% seaweed concentrate to the medium improved plantlet quality and led to better establishment in the greenhouse. No beneficial effect of seaweed concentrate in the tissue culture medium was observed if a second cutting was part of the micropropagation process. Additional application of 0.5% seaweed concentrate in the greenhouse to plantlet cuttings derived from tissue culture was not beneficial.     

The use of image analysis to study developmental variation in micropropagated potato (Solanum tuberosum L.) plants

Summary Potato leaf morphology changes during plant development with the phase shift from vegetative growth to flowering. Image analysis can detect differences in leaf morphology and has been used here to distinguish differences in leaf morphology between potato crops derived from seed tubers and minitubers and between crops derived from different micropropagation protocols. Further, leaf shape parameters can be used to determine the relative maturity of crops. This finding is of economic importance since differences in plant development, for example delayed flowering, are associated with yield parameters. It is hypothesised that image analysis of established microplants can be used as an early evaluation of micropropagation protocols for potato.     

Rice with fish culture in the semi-deep waters of the Mekong Delta, Vietnam: a socio-economical survey

The results of a socio-economical survey of farming systems practising rice culture with introduced fish, rice culture with indigenous fish and rice monoculture in the semi-deep waters of the Mekong Delta, Vietnam, are presented. Rice and fish yields, inputs, and cost-benefits were computed to evaluate the agricultural effects of rice with fish culture. Household size, labour availability and educational level were not significantly different among the three farming systems. Rice-fish farming systems differed mainly from rice monoculture by a higher fertilizer/ water requirement and less pesticide use. The total farm cash and net return did not differ among the farming systems. The main beneficial effects of rice-fish culture are thought to be related to environmental sustainability, system biodiversity, farm diversification and household nutrition.     

Percentage of Ubiquitinated Spermatozoa does not Correlate with Fertilizing Capacity of Thawed Bovine Semen

In the spermatozoa of some species, the ubiquitin–proteasome system detects altered proteins and tags them for elimination by the proteasome. In some species' ejaculates, a high proportion of ubiquitinated spermatozoa (i.e. those having ubiquitin bound to the altered or damaged membrane proteins) has been related to infertility. The aim of this study was to assess whether the percentage of ubiquitinated spermatozoa relates to fertility of dairy bulls and whether ubiquitination increases during protein remodelling that occurs during in vitro spermatic capacitation. Thirty‐two frozen semen straws from four high‐fertility (ReproMax^®) and four normal‐fertility (Normal) Holstein‐Friesian sires were evaluated. Ubiquitinated and capacitated spermatozoa were quantified by sperm ubiquitin tag immunoassay and chlortetracycline stain, respectively. Fertilizing capacity of sires was assessed by in vitro fertilization. No differences were found between Normal and ReproMax^® sires with regard to the observed percentage of ubiquitinated spermatozoa (42.97 ± 3.69% and 49.68 ± 9.27%, respectively; p > 0.05). Additionally, no differences were found in the percentage of ubiquitinated spermatozoa as a consequence of spermatic capacitation in either Normal (42.97 ± 3.69% before capacitation vs 44.67 ± 7.5% after; p > 0.05) or ReproMax^® sires (49.68 ± 9.27% before vs 45.05 ± 7.51% after; p > 0.05). The percentage of ubiquitinated spermatozoa in a thawed sperm samples did not correlate with its in vitro fertilizing capacity; thus, this assay does not prove useful to detect in vivo fertility differences between sires. Additionally, protein degradation occurring during remodelling of the spermatozoon plasma membrane during the capacitation process does not seem to involve the ubiquitin–proteasome system.     

Prophylactic efficacy of four antibacterial shampoos against Staphylococcus intermedius in dogs

Prophylactic efficacy of 4 antibacterial shampoos against Staphylococcus intermedius in dogs was determined by use of a controlled quantitative technique. Ten adult Beagles were used in the study. The antibacterial agents in the shampoos were 3.0% benzoyl peroxide, 0.5% chlorhexidine acetate, 1.0% available iodine as a polyalkyleneglycol-iodine complex, and a combination of 0.5% triclosan, 2.0% sulfur, and 2.0% salicylic acid. Treated and control sites were challenge exposed with 5.30 +/- 0.10 (log10) S intermedius colony-forming units (CFU)/cm2 of skin and occluded for 5 hours. At the end of the test period, remaining bacteria were removed with a detergent cup-scrub technique and the total number of S intermedius CFU/cm2 skin was calculated for each treated and control site. Nontreated bacteria-challenged control sites yielded 5.62 +/- 0.65 S intermedius CFU/cm2 of skin. Staphylococcus intermedius recovery (CFU/cm2) from the treated sites was 0.94 +/- 0.76 for benzoyl peroxide, 1.96 +/- 1.33 for chlorhexidine acetate, 3.11 +/- 0.48 for organic iodine, and 4.69 +/- 0.23 for triclosan-sulfur-salicylic acid. Each S intermedius recovery value from the 4 treated sites was significantly (P less than 0.05) lower than that from the nontreated S intermedius challenge-exposed control site. Bacteria recovery values were also significantly (P less than 0.05) different among the 4 shampoo-treated sites. We concluded that all shampoos had significant (P less than 0.05) prophylactic activity against S intermedius over 5 hours. The shampoo containing benzoyl peroxide was determined to have the greatest efficacy among the products tested.     

Udder health implications of premature bovine mammary regression. I. Clinical, subclinical and reducing-sugar changes in milk during 168 hours of suspended milking in mid-lactation

The investigation involved 4 mastitis-free cows, exposed to 168 h of suspended milking to induce prolonged milk stasis and premature mammary regression during mid-lactation. After 48 h the milk stasis elicited mastitis-like changes in the clinical, somatic cell count (SCC), bovine serum albumin (BSA) and beta-N-acetyl-D-glucosaminidase (NAG) characteristics of the udder secretions. Such changes in secretions from non-mastitic regressive mammary glands raise doubts about the present knowledge, definition, and diagnosis of so-called non-specific or aseptic mastitis. Determinations of fluctuating lacteal concentrations of lactose, galactose, mannose and glucose suggest that the secretory epithelium altered its metabolism and integrity in response to the intramammary perturbation by following a certain pattern of regressive adjustments which: (i) were apparently triggered during the initial 24 h of perturbation by disturbed Na-K-ATPase activities, followed by a cascade of changes in ion regulation, carbohydrate metabolism and increased formation of lactic acid as a metabolic end-product; (ii) advanced in a stepwise fashion during 0-24, 24-72 and 72-168 h of perturbation from recognition response to alarm reactions and manifestation of regression respectively; (iii) showed that markedly decreased carbohydrate levels preceded major increases of the SCC, BSA and NAG values; (iv) indicated that after 72 h of milk stasis leucocytic infiltrations sharply increased the SCC to more than 500,000 per ml and accelerated the manifestation of regression. The results of this study imply that extensive premature regression of healthy, and especially, pre-irritated udders could have significant implications for the development of different types of bovine mastitis during lactation and should be further investigated.