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,...     

Identification of PCR markers linked to different Or genes in sunflower

Broomrape is a parasitic plant that significantly decreases yield of sunflower. Breeding for resistance has proved to be the most efficient method for suppressing broomrape infestation in the field; however, new races of parasite constantly emerge, and new resistance genes need to be discovered and introduced into cultivated sunflower lines. The aim of this work was to test SSR markers from linkage group 3 (LG3) to investigate whether they could be used for identification of a particular Or gene. Twenty sunflower inbred lines were used, and polymorphism between the lines with various resistance genes and genetic background was investigated. The used markers revealed DNA polymorphism between the investigated lines. Strong association of markers from LG3 with Or₆, as well as Or₄ and Or₂ genes, was found. Identified markers could be used for introduction of these resistance genes into commercial sunflower lines and for establishment and identification of differential lines.     

Early shoot and root growth dynamics as indicators for the survival of black poplar cuttings

The relationship between early root and shoot formation at the beginning of the vegetation period and cutting survival on sandy and loamy fluvisol for 14 genotypes of black poplars was analyzed. Considerable cutting mortality was observed only within the first 80 days since planting. Intensive root formation in the first 20 days since the planting and vigorous shoot growth and development in subsequent 20 days was observed in easy-to-root genotypes. Coefficients of correlation revealed close relationship between early root and shoot growth and development and cutting survival of tested genotypes. The obtained results could be used in the breeding process, as well as for the design of cultivar-adjusted nursery and plantation establishment technology. Tested shoot characteristics, were found to be especially interesting since they could be measured rapidly, by non-destructive means.     

New approach to border line evaluations for whole sample of Williams pear (Pyrus communis)

In many processes of heat exchange, as well as in other processes of biomaterial handling, physical properties of fruit such as dimensions, shape, surface area and volume are of crucial importance. The objective of this work was to find a function which approximates pear border line, as precisely as possible, in order to calculate the surface area and volume of a pear by means of integral calculus. Previously described estimation of an average pear border line was based on the sixth order polynomial and proposed algorithm. Two new ways to calculate the Williams pear border line are the focus of this study. The first way includes spline functions as an estimation of a pear border line (i.e. four third order polynomials), while the second one uses regression function obtained by nonlinear regression method. The regression function has two independent variables, length and total length of a pear. The most precise approximation of a pear border line was obtained by nonlinear regression with R² = 97.48. This was more obvious when total pear length was smaller or greater than average total pear length. Border lines of all tested pears were determined by one regression function with large precision. Therefore, it is safe to calculate surface area and volume of a pear based on regression function and total pear length, only. Calculated volumes of the pears were compared with volumes measured by Archimedes’ method. The smallest relative error has been obtained when the volumes were calculated using the regression function as approximation of pear border line.     

Slaughterline records of various postmortem pathological lesions and their influence on carcass and meat quality in slaughtered pigs

The aim of this study was to identify the prevalence of pathological lesions in pigs from small‐scale farms and to determine associations between pathological lesions and hematological parameters, and carcass and meat quality in slaughtered pigs. The study was conducted on 625 pigs (~115 kg) originating from 20 small‐scale farms. Any signs of pneumonia, pleurisy, pericarditis, and liver milk spots were recorded as present or absent. Complete blood count was investigated. The following carcass quality parameters were measured: live, hot and cold carcass weights, cooling loss, dressing percentage, backfat thickness, and meatiness. Meat pH and temperature were measured 45 min postmortem. Of the 625 examined pigs, 41.8% had pneumonia, 23.5% pleurisy, 2.7% pericarditis, and 29.9% liver milk spots. The presence of pathological lesions in slaughtered pigs adversely affected hematological parameters, reduced live, hot and cold carcass weights, and meatiness and had deleterious effects on meat quality (higher pH_45min and higher prevalence of dark, firm and dry meat). In conclusion, this study showed a high prevalence of pathological lesions in slaughtered pigs, indicating serious health problems in smallholder pig production systems. The presence of single and, especially, multiple pathological lesions in slaughtered pigs negatively affected hematological parameters, and carcass and meat quality.     

Genetic diversity of international bovine viral diarrhoea virus (BVDV) isolates: identification of a new BVDV-1 genetic group

In the last decade, several studies were performed to characterise bovine viral diarrhoea virus (BVDV) isolates and define genetic groups by genotyping. Much data is now available from GenBank, predominantly sequences from the 5' untranslated region (5'-UTR). In order to find out whether genetic grouping of isolates from different countries could be harmonised, 22 new isolates from five countries were analysed in combination with published sequences. Eighteen of these isolates were typed as BVDV genotype 1 (BVDV-1), and one isolate from Argentina and three isolates from Brazil were typed as BVDV-2. BVDV-1 isolates were clustered into five previously defined genetic groups: BVDV-1a, b, d, e and f. Two isolates from Finland and one from Egypt formed a group which was tentatively labelled as BVDV-1j, since statistical support was low. By using a fragment of the Npro gene for typing, we found that these isolates fall into the same group as a deer strain, and are statistically significant. Some Swiss BVDV strains taken from GenBank were found in a new genetic group which was designated as BVDV-1k. The BVDV-2 isolates included in this study seemed to fall into two genetic groups.     

The effect of a single prolonged milking interval on inflammatory parameters, milk composition and yield in dairy cows

A technical stop in automatic milking systems may result in a severely prolonged milking interval (PMI) with subsequent impact on milk somatic cell count (SCC). This study investigated the inflammatory reaction, milk composition and yield during SCC peak observed in composite milk after exposing cows to a single PMI of 24h. At the first milking after the PMI, a sharply increased proportion of milk polymorphonuclear leukocytes (PMN) but marginally increased SCC were observed. The peak in SCC was not seen until morning milking day 2 after the PMI, notably, concomitantly with a decreased PMN proportion. An increase in blood lactose, milk bovine serum albumin and serum amyloid A (SAA) and a drop in milk alpha lactalbumin (ALA) were seen concomitantly with the peak in PMN. All parameters mentioned, had returned to base line after day 2. The changes in SCC and SAA had the longest duration. Lactate dehydrogenase in afternoon milk was decreased during the whole study as was also afternoon milk yield. Interleukin-1β could not be detected in milk at any time. SAA and ALA, respectively, may influence chemotaxis and the changed concentrations observed after the PMI might have contributed to the increased migration of PMN to milk.     

Results of bacteriological and cytological examinations of the endometrium of subfertile mares in stud farms in Serbia

Uterine microbiology, antimicrobial susceptibility and endometrial cytology were investigated in a total of 51 mares with fertility problems from 16 different stud farms in Serbia. Uterine cultures were performed after collection with a double guarded uterine swab, and endometrial cytology was evaluated after collection of endometrial cells with a special device (cytology brush). In 21 of 51 mares, at least one bacterial species was isolated from the uterus; the most frequent were Streptococcus equi subsp. zooepidemicus (13 isolates) and E. coli (four isolates). All isolates of Streptococcus equi subsp. zooepidemicus were susceptible to penicillin. Results from endometrial cytology were inconsistent; in 17 animals with positive bacteriological culture, cytology was not altered. It can be concluded that in Serbia, as in many other contries, Streptococcus equi subsp. zooepidemicus is the main cause for equine endometritis. It can be easily diagnosed by uterine culture but endometrial cytology does not always prove the existence of an endometrial infection with this agent.     

Spatial distribution of Dermacentor reticulatus tick in Slovakia in the beginning of the 21st century

A new field survey monitoring the spatial distribution of Dermacentor (D.) reticulatus (Fabricius, 1794) tick in Slovakia was carried out in 2005–2008 in order to record changes in its distribution when compared to former studies. Last surveys on the geographical distribution were conducted in 1950s and 1970s and the presence of D. reticulatus was determined along the rivers in the south-east (Latorica) as well as in the south-west (Morava, Dunaj) Slovakia. In the present survey new areas with D. reticulatus occurrence were detected, providing evidence that this tick species has extended its range in the surroundings of its former habitats but also by at least 200 km further North and by 300 m of elevation into higher altitudes. D. reticulatus is known to transmit Babesia spp. causing babesiosis in cattle and dogs. Expansion of D. reticulatus range is therefore likely to bring a spread of babesiosis, which can be severe or fatal especially for dogs.