Influence of zearalenone on reproductive system cell proliferation in gilts

Zearalenone (ZEA) is a macrocyclic lactone, estrogenic, diet-depending and fusaric micotoxin, which is produced on many kinds of cereals and feeds in the favourable conditions of humidity and temperature. The structure of ZEA is similar to the structure of estrogens and it enables binding to the estrogenic receptors. The stimulation of protein synthesis in the cells of the reproductive system, which causes intensification of cell proliferation, is one of the effects of ZEA actions. Oedema and vulva reddening are the clinical, external signs of ZEA intoxication in pigs. The aim of this study was to designate the degree of reproductive cell proliferation after low doses of ZEA were applied per os in sexually immature gilts with simultaneous monitoring of zearalenone and alpha-zearalenol levels in peripheral blood. The following were observed in the gilts examined fluctuations of zearalenone and alpha-zearalenol levels in blood, which were connected with entero-hepatic circulation and also numerous histopathological changes in ovarian follicle structure. These changes were present in the reproductive system of sexually immature gilts with a big contribution of PCNA-positive cells. The studies show that zearalenone application in sexually immature gilts caused ovarian follicle atresia and apoptoso-like changes in granule cells. Intensified cell proliferation, which was expressed with the growth of PCNA index, was observed in uterus and oviduct.     

Involvement of high-density lipoprotein in stimulatory effect of hormones supporting function of the bovine corpus luteum

The hypothesis that epinephrine (noradrenaline, NA) enhances utilisation of high-density lipoproteins (HDL) by bovine luteal cells and that this process involves phospholipase (PL) C and protein kinase (PK) C intracellular pathway was tested. Luteal cells from days 2-4, 5-10 or 11-17 of the oestrous cycle were preincubated for 20 h. Subsequently DMEM/Ham's F-12 medium was replaced by fresh medium and the cells were treated for 6 h as follows: In Experiment I with HDL (5-75 micrograms cholesterol per ml), NA, isoprenaline (ISO) or luteinising hormone (LH). In Experiment II cells were incubated for further 24 h in deficient medium (without FCS) and next treated as in Experiment I. In Experiment III cells were stimulated with NA, ISO or LH alone and together with HDL. In Experiment IV cells were treated with PLC inhibitor (U-73122) or with PKC inhibitor (staurosporine) or stimulator (phorbol 12-myristrate 13-acetate) and with either NA, insulin or LH. Only luteal cells from days 5-10 of the cycle responded on HDL and beta-mimetics (P < 0.05). LH stimulated progesterone secretion from the luteal cells during all stages of the cycle (P < 0.001). Cells incubated in deficient medium and supplemented with HDL secreted as much progesterone as those stimulated by LH in all stages of the cycle. Beta-mimetics were unable to enhance the stimulatory effect of HDL. Blockade of PLC had no influence on progesterone secretion from cells treated with either NA or LH, but this did impair the stimulatory effect of insulin (P < 0.05). Similarly, blockade of PKC by staurosporine impaired (P < 0.05) the effect of insulin only but not that observed after LH or NA treatment. We suggest that: (a) noradrenergic stimulation does not enhance utilisation of cholesterol from HDL for progesterone secretion; (b) the fasting of luteal cells seems to activate enzymes responsible for the progesterone synthesis; (c) effect of NA on progesterone secretion from luteal cells does not involve the PLC-PKC pathway.     

The influence of restraint immobilization stress on the concentration qf bioamines and cortisol in plasma of Pietrain and Duroc pigs

Forty-five Duroc (recognized as not susceptible to stress) and 34 Pietrain (susceptible to stress) pigs were subjected to immobilization stress in a prone position for 5, 15, 30 and 60 min. Plasma concentrations of epinephrine (E), norepinephrine (NE), dopamine (DA) and cortisol (C) were determined in response to restraint stress. The concentrations of E, NE and DA were different between the two strains of pigs (some significant interactions); the highest response was seen after 5 min of stress. The concentration of plasma C increased with duration of stress and there was a significant interaction between strain of animals and the time of stress. Our data substantiate the use of E, NE, DA and C as indicators of stress in swine as early as 5 min after exposure to the stressor. It is also shown that stress-susceptible Pietrain pigs had higher plasma concentrations of E, NE and DA than Duroc pigs.     

Changes in technical efficiency of the broiler production in Poland, 1994–2013

1. The effects of changes in technical efficiency on the increase of broiler production are presented for the period 1994–2013 based on the panel data from seven farms located in southern and central Poland. A total of 766 cycles were analysed.

2. The Cobb–Douglas production function was used to assess the changes of output elasticities as well as technical changes in broiler production, for 5-year sub-periods separately.

3. Technical indices of broiler production significantly improved between years 1994–2013: feed conversion ratio decreased from 2.50 kg/kg to 1.78 kg/kg, mortality rate from 8.8% to 4.0% and daily weight gain increased from 37.1 g/d to 58.7 g/d, respectively.

4. Before accession to the EU, there was a substantial increase of fixed capital connected with modernisation of buildings and equipment. In the period 1994–2013, inputs of fixed capital per kilogram of livestock increased by 72% and at the same time the input of labour decreased by 56%.

5. Technical changes in years 1994–1998 contributed to a rapid production increase at a rate of 4.6% annually and only by up to 0.7% annually during 2009–2013. The slowdown of production rate increase after 2009 was partially caused by decreasing the stocking density.     

Plant P5C reductase as a new target for aminomethylenebisphosphonates

A series of N-substituted derivatives of aminomethylenebisphosphonic acid were evaluated as potential inhibitors of delta1-pyrroline-5-carboxylate reductase (EC 1.5.1.2), the enzyme that catalyzes the last step in proline biosynthesis, partially purified from Arabidopsis thaliana suspension cultured cells. At millimolar concentrations, three compounds out of 26 were found to interfere with the catalytic mechanism. One of them, namely, 3,5-dichloropyridyl-aminomethylenebisphosphonic acid, retained such inhibitory activity in the micromolar range. Kinetic analyses ruled out the possibility that the inhibition could simply rely upon the chelating properties of bisphosphonates and showed mechanisms of a noncompetitive type against NADH and an uncompetitive type against delta1-pyrroline-5-carboxylic acid, with KI values of 199 +/- 6 and 10.3 +/- 1.5 microM, respectively. A computer-aided docking analysis, performed on the basis of the crystal structure of the enzyme from Streptococcus pyogenes, suggested that this phosphonate may interact with amino acid residues near the binding site of delta1-pyrroline-5-carboxylic acid, thus blocking the substrate in a pocket and preventing its interaction with NADH. Because in higher plants the step catalyzed by delta1-pyrroline-5-carboxylate reductase is shared by all pathways leading to proline synthesis, such a compound may represent a lead structure to be exploited for the design of new substances endowed with herbicidal activity.     

Detection of equine X chromosome mosaicism in a mare using an equine X whole chromosome painting probe (WCPP)--a case report

An infertile mare with hypoplastic ovaries was subjected to cytogenetic analysis. Fluorescence in situ hybridisation (FISH) using the equine X whole chromosome painting probe (WCPP) was carried out on a chromosome preparation obtained from blood lymphocyte culture. The number of analysed spreads was high (235) and in the X chromosome aneuploidy in mosaic form was diagnosed. The karyotype formula was 63,X / 64,XX / 65,XXX. The ratio of the three lines was 15%, 82% and 3%, respectively. The application of the FISH technique with WCPP is discussed.     

The examination of biophysical parameters of skin (transepidermal water loss, skin hydration and pH value) in different body regions of normal cats of both sexes

The purpose of this study was to evaluate transepidermal water loss (TEWL), skin hydration and skin pH in normal cats. Twenty shorthaired European cats of both sexes were examined in the study. Measurements were taken from five different sites: the lumbar region, the axillary fossa, the inguinal region, the ventral abdominal region and the left thoracic region. In each of the regions, TEWL, skin hydration and skin pH were measured. The highest TEWL value was observed in the axillary fossa (18.22g/h/m(2)) and the lowest in the lumbar region (10.53g/h/m(2)). The highest skin hydration was found in the inguinal region (18.29CU) and the lowest in the lumbar region (4.62CU). The highest skin pH was observed in the inguinal region (6.64) and the lowest in the lumbar region (6.39). Statistically significant differences in TEWL were observed between the lumbar region and the left side of the thorax region (P=0.016), the axillary fossa (P=0.0004), the ventral region (P=0.005), and the inguinal region (P=0.009). There were significant differences in skin hydration between the lumbar region and the left thorax (P=0.000003), the axillary fossa (P=0.002), the ventral abdomen (P=0.03), and the inguinal region (P=0.0003) as well as between the thorax and the ventral abdomen (P=0.005). TEWL was higher in females (15g/h/m(2)) than in males (4.57g/h/m(2)). Skin hydration was higher in females (13.89CU) than in males (12.28CU). Significant differences were not found between males and females for TEWL and skin hydration. Skin pH was higher in males (6.94) than in females (6.54), which was significant (P=0.004).     

The effect of Lactobacillus acidophilus and Bifidobacterium spp. administration on the morphology of the gastrointestinal tract, liver and pancreas in piglets

The aim of the study was to investigate the influence of administration of probiotic bacteria on morphology of the gastrointestinal tract, liver and pancreas. The experiment was performed on 15 piglets at the age from 3 to 35 days, intragastrically administered with Bifidobacterium breve, B. animalis, and Lactobacillus acidophilus bacteria. In all piglets examined, the development of the gastrointestinal tract, liver and pancreas was observed to progress normally. After microflora administration to the piglets, an increase in the number of fibrocytes and fibroblasts was observed in the mucosa lamina propria of stomach and intestines. An increase was also reported in the number and activation of endocrine cells in the stomach and small intestines. The activity of alkaline and acid phosphatases, as well as succinic (SDH) and lactic (LDH) dehydrogenases, was found to be higher after the administration of probiotics. The administration of bacteria, especially of Lactobacillus acidophilus, caused an increase in the number of lymphocytes and lymphoid cells in lamina propria and intraepithelial lymphocytes in the small intestine. Enhanced proliferation of crypt cells was observed in the crypts of intestinal glands; however, there were no statistically significant differences in the PCNA index between the control and probiotic-administered groups. The performed study showed that the administration of probiotic bacteria has no negative impact on the morphology of the gastrointestinal tract, liver and pancreas and is found beneficial to its functioning and immune processes.     

Identification and characterization of bacteria isolated from crown galls on stone fruits in Poland

Eighty stone fruit nurseries located in different regions of Poland were examined for the presence of crown gall affected plants. The disease was observed in 39 nurseries, and galls were sampled for bacterial isolation. Out of 1213 isolates, 409 were pre‐identified as Agrobacterium/Rhizobium spp. with 23S rDNA‐based multiplex PCR, and out of these, 315 were pathogenic when tested on sunflowers. Sequence analysis of three housekeeping genes (fusA, recA, rpoD) revealed that 366 strains belonged to Rhizobium rhizogenes, 23 to Agrobacterium tumefaciens species complex, and the rest of the strains were allocated to new phylogenetic lineages. Of these, the most numerous was the lineage allocated in the Pararhizobium genus. Positive results obtained from pathogenicity tests were generally in agreement with results obtained by PCR with primers complementary to T‐DNA except for two strains, which were positive for PCR but negative for the pathogenicity test. All detected Ti plasmids were nopaline‐type. Independent of their pathogenicity, 59% of tested strains were not sensitive to agrocin 84 in in vitro tests. Analysis of biochemical and physiological features distinguished 50 groups with different phenotypic profiles, but the tested traits were not consistent for strains classified to one taxon. This finding shows limited value of biochemical tests in identification procedures. The bacteria causing tumours were heterogeneous and strains classified to different taxa were found even in a single tumour.