Integrative approach of histopathology and histomorphometry of common carp (Cyprinus carpio L.) organs as a marker of general fish health state in pond culture

The semi‐intensive system of common carp monoculture in earthen ponds is currently the most practiced fish rearing system in several countries in Eastern Europe. This system is based on the addition of supplemented feed to ponds to achieve faster growth. In this study, the general state of the fish health was monitored when three different types of feeds were used: grain cereals (CF), commercial pelleted feed and extruded feed. The markers used were: (i) the histopathological index (HP) of the main organs: gills, liver and kidney; and (ii) the histomorphometric parameters of the hepatocytes and enterocytes to assess the state of the digestive system in fish fed different types of supplemented feed. At the end of the experiment, the fish were in good health, since irreversible lesions were not noticed to a greater extent in any of the fish organs. There were also no other severe lesions present. However, the results showed differences in the HP indices of the liver and gills, as well as the total HP index, indicating a better health status of the fish in the CF group. The histomorphometric results showed larger cytoplasmic areas of hepatocytes in fish fed CF, which is attributed to glycogen accumulation and higher numbers of goblet cells in the distal intestines of fish fed compound feeds. This can be attributed to slight inflammation.     

Voles and weasels in the boreal Fennoscandian small mammal community: what happens if the least weasel disappears due to climate change?

Climate change, habitat loss and fragmentation are major threats for populations and a challenge for individual behavior, interactions and survival. Predator–prey interactions are modified by climate processes. In the northern latitudes, strong seasonality is changing and the main predicted feature is shortening and instability of winter. Vole populations in the boreal Fennoscandia exhibit multiannual cycles. High amplitude peak numbers of voles and dramatic population lows alternate in 3–5‐year cycles shortening from North to South. One key factor, or driver, promoting the population crash and causing extreme extended lows, is suggested to be predation by the least weasel. We review the arms race between prey voles and weasels through the multiannual density fluctuation, affected by climate change, and especially the changes in the duration and stability of snow cover. For ground‐dwelling small mammals, snow provides thermoregulation and shelter for nest sites, and helps them hide from predators. Predicted increases in the instability of winter forms a major challenge for species with coat color change between brown summer camouflage and white winter coat. One of these is the least weasel, Mustela nivalis nivalis. Increased vulnerability of wrong‐colored weasels to predation affects vole populations and may have dramatic effects on vole dynamics. It may have cascading effects on other small rodent–predator interactions and even on plant–animal interactions and forest dynamics.     

Analysis of genetic diversity among Macrophomina phaseolina (Tassi) Goid. isolates from Euro-Asian countries

Journal of Plant Diseases and Protection - The study assessed the genetic variability among Macrophomina phaseolina (Tassi) Goid. isolates originating from six different countries (Turkey,...     

Comparison of a commercial ELISA with the modified agglutination test for the detection of Toxoplasma gondii infection in naturally exposed sheep

Surprisingly few commercial ELISAs are available for the detection of Toxoplasma gondii infection in animals, and none for use in sheep have been evaluated. We thus compared the Bommeli Diagnostics ELISA Toxotest for the detection of T. gondii antibodies in ruminants with the reference modified agglutination test (MAT) in a series of 180 sheep sera. ELISA results were analysed at two cut-off levels (30%, comprising both weakly positive and positive results, and 100%, comprising only positive results), and compared with MAT at three cut-off levels (titre of 1 : 25, 1 : 50 and 1 : 100). The results showed a moderate agreement of ELISA at both cut-offs (kappa = 0.46 and 0.51) with MAT at a cut-off titre of 1 : 100. However, the specificity and positive predictive value were above 95% only at an ELISA cut-off of 100%, indicating its potential as a diagnostic test, particularly in areas with a high prevalence of infection. On the other hand, lower sensitivity and negative predictive value limit its value as a screening test. Thus, the ELISA Toxotest may be used for quick diagnosis of T. gondii infection in sheep in the field, i.e. for the differential diagnosis of ovine abortion storms.     

Distribution and Genotypic Characterization of Campylobacter jejuni Isolated from Poultry in Split and Dalmatia County,Croatia

Consumption of poultry contaminated with Campylobacter jejuni has been recognized worldwide as the leading cause of campylobacteriosis. Therefore, the aim of our study was to investigate the prevalence and genotype diversity of Campylobacter jejuni in poultry meat intended for consumption in Split and Dalmatia County, which is the second biggest County in Croatia. Furthermore, we also wanted to discover possibly stable clones of C. jejuni appearing in different samples and periods of time, which would indicate their ability to persist in or adapt to poultry. In the period from March 2008 until June 2010, 834 samples of poultry from various sources were examined using a surface swab technique. Isolation of C. jejuni was performed by Preston broth and Karmali agar. Identification of the isolates was carried out using biochemical tests. C. jejuni was found in 84 of 574 chicken samples (14.6%) and in nine of 260 samples of turkey (3.5%). Pulse‐field gel electrophoresis (PFGE) was used to analyse 61 obtained isolates using SmaI and KpnI. Of 22 different macrorestriction profiles (MRP) that were found, five were detected in poultry from both different locations and periods of time. Samples from 11 locations were found to be contaminated with more than two different genotypes of C. jejuni. Interestingly, the same MRP were found both in poultry declared to be of domestic origin and in the poultry imported from abroad. The prevalence of C. jejuni in poultry samples was in accordance with previously reported results. Genotypic analysis indicated that the population of C. jejuni in Split and Dalmatia County was diverse and that multiple strains of C. jejuni could be found in the same poultry samples. Furthermore, the same genotypes were identified from the samples obtained from different locations and periods of time, which could support the theory of a global existence of certain MRP that are able to persist in or adapt to poultry.     

Fructose 1,6-biphosphate aldolase in the sera of Simmental young bulls Connection with the fattening capacity, muscle quantity and protein content

SUMMARY: The activity of enzyme aldolase (ALD) was determined in the sera of Simmental young bulls, with the purpose to see whether there exists a relationship between the enzyme activity and fattening capacity and whether the ALD could be an indicator of the muscle quantity and protein content. Early ALD activity was correlated with slaughter weight and ADG in the last fattening month. The regression analysis suggests that young bulls with higher serum ALD acitivity at the start of the experiment had more total muscles and less bone in the analysed rib part. On the basis of ALD activity in the first fattening month it was possible to estimate protein and fat content in the MLD. ZUSAMMENFASSUNG: Fructose-1,6-biphosphat Aldolase beim Serum Simmentaler Jungbullen. Beziehung zwischen Mastf?higkeit, Muskelmenge und Proteingehalt Aldolase (ALD) Enzymt?tigkeit im Serum von Simmentaler Jungbullen wurden in Hinblick auf eine Beziehung mit Mastf?higkeit, Muskelmenge und Proteingehalt untersucht. Es zeigt sich eine Korrelation zwischen früher ALD Aktivit?t und Schlachtgewicht und Tageszuwachs im Endmastmonat. Regressionsanalyse ergab, da? Jungbullen mit h?herer ALD Aktivit?t bei Mastbeginn mehr Muskelanteil im m. longissimus dorsi und weniger Knochen besitzen. ALD Aktivit?t im ersten Mastmonat erlaubt Sch?tzung des Protein- und Fettgehalts im m. long, dorsi. RESUMEN: Fructosa 1,6-bifosfato aldolasa en el suero de los terneros simentales. Relatión con sus capacidades de ser cebados, su cantidad de músculos y el contenido de proteínas Con el fin de establecer la relación entre la actividad de enzimas y las capacidades durante el proceso de la ceba, asf como para precisar si el ALD puede servir como indicador de la cantidad de músculos y el contenido de proteinas, intentaba determinarse la actividad de los enzimas de aldolasa (ALD) en el suero de los terneros simentales. A base de la actividad indicial del ALD, es posible estimar el peso final de matadero y la crecencia diaria media durante el último mes de la ceba. Tras una análisis regresiva se ha probado que los terneros con una actividad mayor del ALD en el suero a principios del proceso de su ceba tienen más músculos en total en la parte de costillas y m. longissimus dorsi mientras que tienen menos huesos. A base de la actividad del ALD durante el primer mes de la ceba es posible estimar el contenido de proteinas y grasa en m. long, dorsi. RéSUMé: Fructose 1.6-biphosphate aldolase dans le sérum des taurillons de Simmental. Le rapport entre l'aptitude à l'angraissement, la proportion des muscles et la teneur en protéines On a déterminé l'activité de l'enzyme aldolase (ALD) dans le sérum des taurillons de Simmental afin de vérifier s'il existait un rapport entre l'activité des enzymes et l'aptitude à l'engraissement et si l'ALD pouvait être indicatrice de la proportion de muscles et de la teneur en protéines. A la base de l'activité initiale de l'ALD, il est possible d'évaluer le poids de la carcasse et le gain quotidien moyen au cours du dernier mois d'engrais. Par analyse régressive, il a été établi que les taurillons à l'activité supérieure de l'ALD dans le sérum avaient au début de l'engrais plus de muscles au total dans la région costale et le m. longissimus dorsi et moins d'os. A la base de l'activité de l'ALD au cours du premier mois d'engrais il est possible d'évaluer la teneur en protéines et en graisse dans le muscle longissimus dorsi.     

Multilocus PCR assay reveals high diversity of vegetative compatibility types in populations of Cryphonectria parasitica in Croatia

The ascomycete fungus Cryphonectria parasitica, causal agent of chestnut blight, is probably one of the best known invasive fungal pathogens in forests of Europe and North America. Mycovirus that reduces virulence of C. parasitica can be used as a biocontrol agent of the chestnut blight. However, anastomosis‐mediated virus transmission is limited by a vegetative (in)compatibility (vc) system involving at least six known diallelic vic genetic loci. This study looked at vegetative compatibility (vc) diversity in two populations of C. parasitica in Croatia. For that purpose, a PCR assay was validated and implemented using already known/published and newly designed primers for amplification of six known vic loci. The vc genotypes determined by PCR for 158 C. parasitica isolates investigated in this study were in complete agreement with the vc genotypes determined by pairwise co‐culturing of the same isolates, revealing the specificity and accuracy of the PCR‐based molecular vic genotyping assay. Twenty‐six unique vc genotypes were found among 158 isolates, and 19 vc types per population, which makes Croatian C. parasitica populations among the most diverse in Europe regarding the number of vc types and genetic diversity. Low values of multilocus linkage disequilibrium suggest sexual reproduction as a major contributor to high C. parasitica genetic diversity in studied populations.     

Plasma parathyroid hormone-related peptide and bone metabolism in periparturient dairy cows

The first weeks of lactation in dairy cows are characterised by elevated bone resorption. The connection between lactation and bone metabolism is still much discussed. In this work, changes in the concentration of plasma parathyroid hormone-related peptide (PTHrP) and markers of bone metabolism were studied in Holstein cows and heifers in the dry period and early lactation to determine the role of PTHrP in the relationship between the rate of bone remodelling and the onset of lactation in dairy cows. Blood samples were taken 14 days before calving ('D-14', n = 23) and then on day 10 ('D+10', n = 21) and day 30 after calving ('D+30', n = 23). Using enzyme immunoassay (EIA), the concentrations of PTHrP, parathyroid hormone (PTH), carboxyterminal cross-linked telopeptide of type I collagen (CTX) and oestradiol and the activity of bone specific alkaline phosphatase (BSALP) were determined. The results showed a statistically significant increase in plasma PTHrP (p < 0.005) and CTX (p < 0.0001) in cows on 'D+10' as compared to 'D-14' and CTX on 'D+30' as compared to 'D-14' (p < 0.0001). Significant negative correlations were found between the concentrations of PTHrP and oestradiol (r = -0.29, p < 0.05) and those of CTX and oestradiol (r = -0.54, p < 0.0001). In nonpregnant heifers (n = 6), the concentration of CTX and the activity of BSALP were significantly higher (p < 0.0001) than in dry cows. The observed increments of PTHrP and bone resorption after parturition reveal adaptations of bone metabolism to lactation in dairy cows.     

Sublethal effects of a synthetic pyrethroid,deltamethrin, on the glycemia,the lipemia,and the gut alkaline phosphatases of honeybees

A sublethal dose (0.1 pmol per honeybee, i.e., approx. 0.9 pmol/g body wt) of the synthetic pyrethroid, deltamethrin, was injected intrathoracically into the hemocoel of emerging bees and the biochemical effects were determined over a period of 3 hr. The variations in hemolymph concentrations of trehalose, glucose, phospholipid, steroid, and diacylglycerol were limited, but large variations were observed for other lipids. Mono- and triacylglycerols increased dramatically 1.5 hr after injections; then a peak of free fatty acid appeared at the same time (3 hr) as the monoacylglycerols reached their maximum and the triacylglycerols started to decrease. Atypical forms of triacylglycerols accumulated from 1.5 hr to a maximum level 2 hr after injection. Then, after 3 hr, the concentrations of regular fatty acids, monoacylglycerols, and atypical triacylglycerols returned to normal while longer-chain fatty acids and different forms of ceride simultaneously appeared. The gut alkaline phosphatase parameters (V_M, K, and Hill coefficient) also showed large variations 1.5 and 2 hr after injection, indicating an initial inhibition phase followed by superimposed induction and inhibition mechanisms. These data are discussed according to the hemolymph-lipid transport scheme from the biosynthetic to the utilization sites. Hormone release associated to mitochondrial alteration could be responsible for the observed effects.