Effects of freezing-thawing on DNA integrity of boar spermatozoa assessed by the neutral comet assay.

A modified version of the neutral comet assay was employed to evaluate the effect of the freezing-thawing process on boar-sperm DNA integrity. The sperm-rich fractions were collected from four mature boars and frozen into aluminium tubes and straws after extension in lactose-hen egg yolk-glycerol extender (lactose-HEY-G) or an extender containing lactose, lyophilized lipoprotein fractions extracted from ostrich egg yolk and glycerol (lactose-LPFo-G). The semen samples were also frozen in a standard boar semen extender (Kortowo-3), without the addition of cryoprotective substances.

Effect of chosen lactic acid bacteria strains on Staphylococcus aureus in vitro as well as in meat and raw sausages.

The present study was aimed at determining the influence of 15 strains of lactic acid bacteria on the growth of 2 Staphylococcus aureus strains in vitro as well as in meat and raw sausages. The investigations were performed within the framework of three alternate stages which differed in respect to the products studied, the number of Lactobacillus sp. strains and, partly, methodological approach.

Effects of dietary supplementation with polyunsaturated fatty acids and antioxidants on biochemical characteristics of boar semen.

The aim of this study was to investigate the effect of providing a supplement containing polyunsaturated fatty acids and antioxidants (PROSPERM) on the biochemical characteristics of boar semen. Two sexually mature boars were fed a standard diet with PROSPERM (250 g daily) for a 24-week period. Ejaculates collected prior to supplementation were used as the control.

Cytogenetic characterization of the Zebra Mussel Dreissena polymorpha (Pallas) from Miedwie Lake, Poland.

Cytogenetic characterization of D. polymorpha was carried out using banding techniques such as C-banding, fluorochrome CMA3 and silver nitrate treatment. The diploid chromosome number of both investigated D.

The use of comet assay to assess DNA integrity of boar spermatozoa following liquid preservation at 5 degrees C and 16 degrees C.

The comet assay, under neutral conditions, allows the assessment of DNA integrity influenced by sperm ageing, which is manifested in DNA double-strand breaks. Here, we attempted to use a modified neutral comet assay test (single-cell gel electrophoresis), to our knowledge for the first time, to assess DNA integrity of boar spermatozoa during liquid storage for 96 h at 5 degrees C and 16 degrees C. In this comet assay protocol we used 2% beta-mercaptoethanol prior to the lysis procedure, to aid in removing nuclear proteins.

Luteotrophic action of prolactin during the early luteal phase in pigs: the involvement of protein kinases and phosphatases.

Prolactin (PRL) involvement in the regulation of luteal steroidogenesis in pigs during the early luteal phase and pregnancy is well documented. The intracellular mechanism of PRL action in steroidogenic cells, however, is not fully recognized yet. In the current study, we have tested the hypothesis that protein kinase C (PKC) and tyrosine kinases (PTK) as well as serine-threonine (PP) and tyrosine phosphatases (PTP) are involved in PRL signaling in luteal cells originated from the early corpora lutea (CL) of cyclic sows.

Are hypothalamic neurons transsynaptically connected to porcine adipose tissue?

Specific anatomical sites and pathways responsible for mediating metabolic and neuroendocrine effects of leptin are still poorly understood. Therefore, we examined distribution of leptin receptor-containing neurons transsynaptically connected with the porcine fat tissue by means of combined viral transneuronal tracing and immunohistochemical staining method. Pseudorabies virus (PRV) was injected into the perirenal fat tissue in pigs, and after survival periods of 3, 5, 7, 9, and 11 days, hypothalami were processed immunohistochemically with primary antisera against PRV and leptin receptor (OBR).

The influence of inflammation on the expression of neuropeptides in the ileum-projecting primary sensory neurones in the pig.

In the present study the ELISA test was used to investigate the influence of chemically-induced ileitis on the dorsal root ganglia (DRG) neurons in the pig. The preliminary retrograde fluorescent tracing study revealed that ileum-projecting sensory neurones (IPN) are located in the thoracic ganglia (Th; Th8-Th13). The ileum wall in experimental (E) pigs was subjected to multiple injection with 4% paraformaldehyde to induce inflammation, while in the control (C) animals the organ was injected with 0.

Distribution of spinal sensory neurons supplying the adrenal gland in the pig.

The present study was aimed at disclosing which spinal ganglia contribute to the innervation of the adrenal gland in the pig with special regard to the morphology and intraganglionic distribution of the primary sensory neurons within these ganglia. To this end, the animals were injected with a retrograde fluorescent neuronal tracer Fast Blue into the left adrenal gland during laparotomy. After a survival period of three weeks, labelled spinal sensory neurons were found in the ipsilateral dorsal root ganglia (approximately 99% of all retrogradely marked neurons).

Distribution of neurons containing leptin receptors in the hypothalamus of the pig.

Leptin, secreted by white adipocytes, has profound feeding, metabolic, and neuroendocrine effects. Leptin acts on the brain, but specific anatomical sites and pathways responsible for mediating these effects are still unclear. We have systematically examined the distribution of leptin receptor containing neurons in the porcine hypothalamus by means of immunohistochemical staining methods.

Effects of ivermectin and albendazole against Anisakis simplex in vitro and in guinea pigs.

The activity of ivermectin and albendazole against larval Anisakis simplex was tested in vitro and in experimentally infected guinea pigs. Before drug exposure the medium for half of the larvae was adjusted to pH 2.0 with 1 N HCl, whereas the other half was held at pH 7.

Leptin receptors, NPY, and tyrosine hydroxylase in autonomic neurons supplying fat depots in a pig.

The goal of this study was to determine the immunohistochemical characteristics of peripheral adrenergic OBR-immunoreactive (OBR-IR) neurons innervating adipose tissue in a pig. The retrograde tracer, Fast Blue (FB), was injected into either the subcutaneous, perirenal, or mesentery fat tissue depots of three male and three female pigs each with approximately 50 kg body weight. Sections containing FB(+) neurons were stained for OBR, tyrosine hydroxylase (TH) or neuropeptide Y (NPY) using a double labeling immunofluorescence method.

Androgenesis in rainbow trout using cryopreserved spermatozoa: the effect of processing and biological factors.

In addition to producing homozygous lines for biomedical and genomic research and monosex stocks for commercial purposes, androgenesis is the biotechnology considered most promising and reliable for recovering complete nuclear genome information from cryopreserved fish cells. That is because procedures of cryopreserving spermatozoa, contrary to procedures for oocytes or entire eggs, are being well developed. Application of androgenesis in genome banking programs addresses the needs of both the aquaculture industry (safeguard for valuable strains and lines) and natural resource conservation (in vitro protection of endangered species or populations).

Relationship between motility and membrane integrity of boar spermatozoa in media varying in osmolality.

A study was conducted to evaluate the relationship between boar sperm motility and membrane integrity following exposure to media with 150-1120 mOsm. Total sperm motility was defined as the percentage of spermatozoa that had any form of motility was subjectively assessed under a light microscope. Sperm cell damage was expressed as a loss of membrane integrity as measured by a combination of fluorescent stains, carboxyfluorescein diacetate (CFDA) and propidium iodide (PI), and Hoechst 33258 (H33258).

Effect of extender composition and equilibration time on fertilization ability and enzymatic activity of rainbow trout cryopreserved spermatozoa.

The effects of extender composition and equilibration time on fertilizing ability of cryopreserved spermatozoa from rainbow trout, Oncorhynchus mykiss, were investigated. In addition, enzyme activity in supernatants from thawed sperm was assessed. The use of the two extenders: Erdahl & Graham's + 10% DMA (dimethyl acetamide) + 10% egg yolk and 0.

Effect of depletion tests (DT) on the composition of boar semen.

We conducted two depletion tests during the summer (DT 1) and winter (DT 2) to study their effect on selected biochemical parameters of boar semen. We subjected three boars to DT for 10 consecutive days. The first 3 days (Period 1) of ejaculate collections represented the reserves of the extragonadal spermatozoa and accessory sex gland secretions, whereas the other seven days (Period 2) represented the daily spermatozoa output and the secretory capacity of the accessory sex glands.