Leukocyte counts in bronchoalveolar lavage fluid obtained from normal and Maedi–Visna‐infected sheep

Background: Bronchoalveolar lavage has proven helpful for the diagnosis of certain ovine diseases of the lungs. There is insufficient data concerning the leukocyte profile of bronchoalveolar lavage fluid (BALF) from MaediVisna infected sheep. Objective: The objective of this study was to assess the differential leukocyte profile of BALF associated with Maedi virus infection in sheep and to determine whether cytologic examination of BALF is an effective way to diagnose Maedi or determine the severity of lung lesions. Methods: BALF and serum samples were analyzed from 400 sheep. Sediment smears of bronchoalveolar lavage were stained with Diff‐Quik and examined microscopically to obtain a 200‐cell differential cell count. Serum was tested using a commercial kit for Maedi–Visna virus antibodies. Lung samples obtained at the time of slaughter were weighed and examined histologically. Results: Maedi‐infected sheep (n=267; seropositive with lung lesions) had a significantly higher percentage of lymphocytes and lower percentage of macrophages in BALF than normal sheep (n=133; seronegative and no lung lesions). These differences were significantly more severe in animals with advanced vs moderate lung lesions. Using classification trees, a cut‐off of 13.5% lymphocytes was predictive of Maedi infection and a cut‐off of 24.5% lymphocytes was predictive of advanced lung lesions. Conclusions: Cytologic examination of BALF is useful for the clinical diagnosis of Maedi in sheep and provides important information about the severity of the lung lesions.     

Experimental staphylococcal mastitis in bitches: clinical, bacteriological, cytological, haematological and pathological features

The objectives of the work were to study the features of experimentally induced canine mastitis and to present hypotheses regarding the pathogenesis of the disease. The right caudal abdominal mammary gland of six bitches was inoculated on day 8 after whelping with Staphylococcus intermedius to induce mastitis; adjacent mammary glands were used as controls. Clinical examination, bacteriological and cytological (whiteside test, Giemsa) examination of mammary secretion, as well as haematological tests were performed from 5 days before until 34 days after challenge. Mastectomy was sequentially performed 1, 2, 4, 18, 26 and 34 days after challenge in each of the bitches, in order to carry out a pathological examination of mammary glands. All animals developed clinical mastitis: challenged glands became painful, hot, enlarged and oedematous; secretion was brownish, purulent, with flakes or clots, subsequently becoming yellowish and thick. Staphylococci were isolated from all inoculated glands (up to 22 days). WST was positive in 41/46 samples from inoculated glands and 66/138 samples from control glands; neutrophils predominated during the acute stage. Blood leukocyte counts increased, whilst platelet counts decreased. Gross pathological findings initially included congestion, purulent discharge and subcutaneous oedema; then abscesses, brownish areas and size decrease were seen. Salient histopathological features were initially neutrophilic infiltration, haemorrhages, destruction of mammary epithelial cells and alveoli, and then infiltration by lymphocytes, shrunken alveoli, loss of glandular architecture and fibrous tissue proliferation. We conclude that in bitches, intrammamary inoculation of Staphylococcus intermedius can induce clinical mastitis, followed by subclinical disease. The disorder is characterized by bacterial isolation and leukocyte influx in challenged glands, by leukocyte presence in adjacent mammary glands, by increased blood leukocyte counts and by destruction of mammary parenchyma.     

Field evaluation of the effect of a probiotic-containing Bacillus licheniformis and Bacillus subtilis spores on the health status, performance, and carcass quality of grower and finisher pigs

The aim of the study was to assess the efficacy of BioPlus 2B, a probiotic containing Bacillus licheniformis and B. subtilis spores, on the health status and productivity of pigs, during weaning, growing and finishing stages of growth. On a commercial farrow-to-finish farm, five experimental groups were formed, each of 54 weaned piglets. The pigs of the first group (double controls) received normal feed with no probiotic and the pigs of the second group (untreated controls) received BioPlus 2B only during the weaning stage. The pigs of the third, the fourth and the fifth group received the same as the second group feed but, at the growing and at a part of the finishing stages, supplemented with three different doses of Bioplus 2B, a low, medium and high dose, respectively. The results have shown that, compared with the double controls, BioPlus 2B-treated pigs had a lower morbidity and mortality during the whole trial period, compared with the double controls (range from 9.26 to 14.81% versus 25.93% and from 0.00 to 3.70% versus 11.1%, respectively), as a result of the lower incidence of post-weaning diarrhoea due mainly to Escherichia coli. Weight gain, feed conversion ratio and carcass quality of the BioPlus 2B-treated pigs were significantly improved compared with the double controls, whilst the beneficial effects of the probiotic were more pronounced when the medium and high doses were used.     

Field evaluation of the efficacy of a probiotic containing Bacillus licheniformis and Bacillus subtilis spores, on the health status and performance of sows and their litters

The aim of this study was to assess the efficacy of BioPlus 2B, a probiotic containing Bacillus licheniformis and Bacillus subtilis spores, on the health status and productivity of sows and their litters. A total of 109 gilts and sows were allocated into two experimental groups, as follows: untreated controls (UC) and BioPlus 2B (same feeding as the UC group plus BioPlus 2B) at a dose of 400 g/ton of feed (equal to 1.28 x 10(6) viable spores/g of feed). Treatment started from the day of allocation (14 days prior to the expected farrowing) up to the weaning day. Homogeneity of the groups was satisfied with regard to the parity. From the results it was evident that BioPlus 2B supplementation of the feed improved gilt/sow performance as shown by: (i) the increase of sow feed consumption during the first 14 days postpartum and (ii) the decrease of sow weight loss during the suckling period. Certain blood and milk parameters were significantly improved, as shown by higher serum cholesterol and total lipids concentrations and higher milk fat and protein content at mid-suckling period. As a consequence, a positive effect was also noticed as regard litter health and performance characteristics in terms of: (i) decrease in piglet diarrhoea score, (ii) decrease in pre-weaning mortality thus leading to increase in the number of weaned piglets per litter and (iii) increase in piglet body weight at weaning. Moreover, BioPlus 2B tended to improve the health status and fertility of sows demonstrating: (i) tendency to a lower proportion of sows with Mastitis-Metritus-Agalactia (MMA) problems and (ii) lower proportion of sows returning to oestrus.     

Parasitism of <Emphasis Type="Italic">Psytallia concolor</Emphasis> (Hymenoptera: Braconidae) on <Emphasis Type="Italic">Bactrocera oleae</Emphasis> (Diptera: Tephritidae) infesting different olive varieties

Psytallia concolor (Szépligeti) is a koinobiont endoparasitoid of many Tephritidae larvae, including Bactrocera oleae (Rossi), and has been used in Mediterranean areas for biological control of olive fruit fly by inundative release. The present study evaluates the influence of olive fruit variety (Amfissis, Arbequina, Branquita de Elvas, Carolea, Kalamon, Koroneiki, Leccino, Manzanilla, Mastoidis, Moroccan Picholine and Picholine) on P. concolor parasitism efficiency and performance in the field during two successive years. The results showed that the percentage of parasitism was significantly higher (>30%) in Mastoidis and Koroneiki (light-weight varieties <1.5 g) than Leccino which has a medium fruit weight, followed by Amfissis, Moroccan Picholine, Picholine and Branquita de Elvas. Only Manzanilla among large weight varieties, exhibited high percentage of parasitization (42.72%) during 2013. The mean weight of the pupae (>4.21 mg) as well as the length of the developed adult parasitoids (>3.5 cm) in Mastoidis and Manzanilla were significantly higher than these individuals developed from other varieties such as Koroneiki and Kalamon. Finally, the optimal host fruit for P. concolor development seems to be Mastoidis variety with great biological parameters and percentage of parasitism.     

Efficacy of an inactivated aqueous vaccine for the control of enzootic pneumonia in pigs infected with Mycoplasma hyopneumoniae

The efficacy of an inactivated aqueous vaccine against Mycoplasma hyopneumoniae was evaluated at two M hyopneumoniae-infected farrow-to-finish commercial farms (A and B) in Greece. In a prospective, randomised double-blind study, two groups on each farm received intramuscular doses of either the vaccine or the adjuvant when they were one and four weeks of age. The pigs were observed daily for clinical signs of disease; morbidity and mortality were recorded; and bodyweight was recorded at intervals. At slaughter, the lungs of the animals were examined and the chest cavities were examined for signs of pleuritis. No adverse reactions to the treatments were observed in any of the pigs. On farm A the vaccinated pigs were on average 6 kg heavier at slaughter, and on farm B they were on average 4 kg heavier; on both farms the average daily gain of the pigs was greater than that of the unvaccinated pigs. The prevalence and severity of enzootic pneumonia in the affected lungs were significantly lower in the vaccinated than in the unvaccinated pigs.     

Investigation of the coagulation mechanism of the suspended particulate matter in coastal waters

The granulometry of the suspended matter in various coastal waters collected around the Patras city in Greece, together with the average particle diameters, have been determined during 12 mo by means of a simple, quick, inexpensive and relatively accurate photosedimentometer. The particle size distributions were found to be self-preserving and independent of time, hydrologic regime, nature and amount of particulate materials and particle mobility. The experimental results show that the Brownian diffusion is the factor dominant in the flocculation processes in coastal waters. The flocculation processes of the suspended particles taking place when river water meets sea water were also investigated.     

Exploitation of heterosis through recurrent selection scheme applied in segregating generations of a tomato breeding program

This paper presents the efficiency of recurrent selection in the segregating generations of recycled lines, obtained via mass selection, in two tomato commercial single-cross hybrids, and the assessment of advanced lines in two farming systems at two different locations. In particular, in the F₃ and F₄ mass selection lines of the hybrids Iron and Sahara, half-sib (HS) selection was applied by crossing within the F₃ and F₄ plants. Two experiments were conducted, the first for evaluating the F₄ mass lines with the HS lines obtained by crossing in the F₃ generation, and the second for evaluating the F₅ mass lines with the HS lines obtained by crossing in the F₄ generation, and the second generation HS lines, which were selected from the first experiment. F₁ and F₄ generations were used as controls, respectively. The HS lines of cv. Sahara overyielded 18–56% the F₄ mass line, while Iron's HS lines presented greater uniformity in yield components and also outperformed qualitatively. The effectiveness of mass selection showed positive realized heritability only for fruit number of cv. Iron. In this study, where evaluation and selection was practiced in the absence of competition, the expected response in heterosis via HS depended on σ²_g. The differences of σ²_g of F₁ from mass and HS lines were positive for both hybrids, while when the control was the F₄ generation, mass lines showed a lower performance and some HS lines showed a higher performance. This means that HS lines have favorable alleles and heterosis. In this sense, Sahara's and Iron's HS lines increased 50.2 and 5.3% the charge of favorable alleles, respectively, compared to the corresponding control. The selected advanced lines were assessed in two farming systems at two different locations; the organic one, where two HS-lines, one from each hybrid, outyielded significantly the control; and the conventional one, where all lines performed equally to the control. The results assume the evidence that stable hybrids incorporate individual buffering into inbred line cultivars.     

Validation of a competitive ELISA for diagnosis of Brucella melitensis infection in sheep and goats

A competitive enzyme-linked immunosorbent assay (cELISA) was validated for the serodiagnosis of Brucella melitensis infection in small ruminants using 2108 positive and 2154 negative reference sera from sheep and goats. The optimum cut-off values, offering the highest diagnostic sensitivity (DSn) and diagnostic specificity (DSp), determined by receiver operating characteristic analysis, were at 23.6%, 21.8% and 25.0% inhibition of the conjugate control for sheep, goats and both species, respectively. The DSns of the cELISA for sheep, goats and both species at these cut-off values were 89.2% (95% confidence interval 87.1-91.1%), 74.0% (95% CI 71.4-76.5%) and 77.9% (95% CI 76.1-79.7%), whereas DSps were 96.4% (95% CI 95.2-97.4%), 92.9% (95% CI 91.1-94.3%) and 97.2% (95% CI 96.4-97.8%), respectively. Compared to cELISA, indirect ELISA and fluorescence polarisation assay have higher DSns and DSps. However, the results obtained with the cELISA were in good agreement with those of the complement fixation test (CFT) under field conditions using 5735 sheep and goat sera. The cELISA can be used as an alternative to the CFT for diagnosing B. melitensis infection in small ruminants.