Tomasz Schwarz

PHYSIOLOGICAL MECHANISMS OF OVARIAN FOLLICULAR GROWTH IN PIGS - A REVIEW

Follicular growth after antrum formation is determined by follicle-stimulating hormone (FSH). Only two ways are possible for recruited follicles, continuing development or atresia. In gilts, intensive ovarian follicular growth begins between 60 and 100 days of age, and fluctuations of the ovarian morphological status last about 20 days; however, at that time there are no really large follicles. Final follicular development is under luteinising hormone (LH) control; this is why the attainment of puberty is related to an increase in serum oestradiol to a level that causes a preovulatory surge of this gonadotropin. The pool of follicles at the beginning of the oestrous cycle is about 30-40, most of which are small (< 3 mm) and growing. Then, the pool of follicles increases to about 80 in the mid-luteal phase but about 50 of them are small and 30 are medium sized (3-6.9 mm). Some of these follicles are in the growing phase, but some are atretic. Between days 7 and 15 of the oestrous cycle the percentage of atretic follicles fluctuates between 12 and 73%. At that time there are no large (> 7 mm) follicles because of the suppressing effect of progesterone. The number of small follicles declines after luteolysis. From the pool of medium follicles, large follicles are selected under the influence of LH, but about 70% of the medium-sized follicles become atretic. Because of the long-lasting selection process there is a significant heterogeneity in the diameter of large follicles in oestrus. However, the number of follicles correlates with the number of corpora lutea after ovulation. Individual follicular development and the relationship between follicles are still poorly known. The use of ultrasonography may give a closer insight into these phenomena.

Defining the histopathological changes induced by nonablative radiofrequency treatment of faecal incontinence - a blinded assessment in an animal model

Nonablative radiofrequency (RF) sphincter remodelling has been used to treat gastro‐oesophageal reflux disease (GERD) and faecal incontinence (FI). Its mechanism of action is unclear. We aimed to investigate the histomorphological and pathophysiological changes to the internal and external anal sphincter (IAS and EAS) following RF remodelling.

Immunolocalization of Androgen Receptor in the Boar Epididymis: the Effect of GnRH Agonist Deslorelin

Epididymides from nine crossbred male pigs [Polish Landrace x (Duroc x Pietrain)] (n = 3 per each group) were used in this study to show whether there are any differences between androgen receptor (AR) distribution along epididymal duct of a GnRH agonist deslorelin-treated boars when compared to the control tissues. The active agent was administered by way of a subcutaneous controlled-release implant containing 4.7 mg deslorelin at 91 or 147 days of age respectively. Boars from two experimental groups and the control group were slaughtered at 175 day of age. Immunolocalization was performed using a polyclonal rabbit antiserum against the AR. In control boars, strong staining for AR was detected in nuclei of the epithelial (principal and basal) and stromal cells, whereas in boars treated with deslorelin the staining was confined to the principal cell nuclei. In those treated for 84 days, AR-immunostaining was weak or the principal cells were negative for the AR. Irrespective of the time from deslorelin insertion all stromal cells were immunonegative. The results demonstrate for the first time the effect of deslorelin on the distribution of the AR in the three regions of the boar epididymis. It is likely that stromal cells are more sensitive than epithelial cells to the regulation of AR expression by androgen. The morphological and functional alterations along the epididymal duct and lack of spermatozoa within the lumen after deslorelin treatment indicate that a potent GnRH agonist is likely responsible for an impairment of the microenvironment created by epididymal cells for sperm maturation and their storage.

Perception of environment in farm animals - a review.

Abstract Perception of the environment by farm animals is fundamental for expression of behaviour and of their adaptation to different environmental conditions. From a breeding-environmental perspective, perception becomes increasingly important when a production system negatively impacts on animals such that their normal expression of behaviour is compromised. Therefore, research on the perceptual abilities of farm animals is of crucial importance to understand the animalenvironment relationship. This review is focused on research related to sensory perception of farm animals. It should be stressed that the world of animal senses is very difficult to explore, we have limited knowledge of the complexity of the animal’s ability to perceive and process environmental stimuli.

The distribution of corpora lutea and ovarian follicular development in pregnant goats.

The main objective of the study was to determine the number of growing follicles (diameter>or=4 mm) with regards to the distribution of corpora lutea (CL) on the ovaries in pregnant goats. Growing follicles with a diameter greater than 5 mm i.e. large follicles were also recorded and analyzed. Daily ultrasonography (USG) examinations of ovaries were made in six Polish White Goats starting from the day of estrus detection (December/January) until parturition (May/June). An individual profile of follicular growth during the entire pregnancy was recorded for every goat. Three goats with CL present only on one ovary were included into group CL/0, and the three other goats with CL on both ovaries were in CL/CL group. The mean numbers of growing (52.0+/-11.3) and large (21.0+/-7.1) follicles during the entire pregnancy in group CL/0 were significantly (p<or=0.05) higher than those of group CL/CL (growing follicles: 30.0+/-2.8, large follicles: 10.0+/-2.8). The mean numbers of growing (13.7+/-2.1) and large (4.4+/-0.9) follicles on the CL-bearing ovary were significantly (p<or=0.01) lower than those on the CL-free ovary (growing follicles: 41.0+/-7.0, large follicles: 18.0+/-5.0). In conclusion, the distribution of CL in the ovaries affected a number of growing follicles during caprine pregnancy. The majority of growing follicles during this period was observed on the CL-free ovaries.

Assessing the efficiency of using a modern hybrid rye cultivar for pig fattening, with emphasis on production costs and carcass quality

There were two goals of the present experiment, namely (1) to determine and compare the concentrations of basal nutrients and anti-nutrients in the grain of a modern hybrid rye and barley cultivars, and (2) to compare the effectiveness of the rye- and barley-containing diets for pig fattening. Crude protein and starch contents were greater (P < 0.01) in rye (cv. Visello) than in barley (cv. Bryl) but fibre and total lipid concentrations were lower (P < 0.01) in rye grain. Mean concentrations of alkylresorcinols and pentosans, as well as the activity of trypsin inhibitors, were all higher (P < 0.01) in rye grain. In all, 150 PIC gilts were randomly divided into two equinumerous groups; control pigs were fed a diet containing barley as the main cereal ingredient (starter phase (SP), 35% of feed content; grower phase (GP), 40% of feed content; and finisher phase (FP), 65% of feed content), while the experimental group received a diet with rye replacing a proportion of barley (10% during SP, 25% during GP and 50% during FP); the diets for both subsets of animals also contained wheat and soybean meal to obtain a proper level of nutritional value. The average weight gain of the rye-fed gilts (783 ± 183 g/day; mean ± s.d.) was greater (P < 0.05) than that of control animals (747 ± 218 g/day). This difference in weight gain was due mainly to an increase in daily feed intake (2.35 ± 0.21 and 2.15 ± 0.19 kg/day in the experimental and control groups, respectively; P < 0.01) recorded during the grower and finisher phase. Carcasses from both groups exhibited the same lean meat content; however, the percentage of carcasses in the higher classes according to the EUROP quality scale tended to be greater in the experimental group, which resulted in a higher (P < 0.05) carcass value than for barley-fed controls. The present results indicated that a modern rye cv. Visello is a safe and cost-effective feed for growing pigs, and yields significantly better outcomes than commonly used barley-containing diets in terms of carcass quality and price.

An Ultrasonographic Study of Ovarian Antral Follicular Dynamics in Prepubertal Gilts During the Expected Activation of the Hypothalamo-pituitary-ovarian Axis

Abstract Daily transrectal ultrasonography was carried out in eight 4–5-month-old Polish Large White × Polish Landrace gilts for 42 days to monitor the growth of individual ovarian antral follicles ≥2 mm in diameter. In total, 52.4 ± 16.2 and 123.0 ± 6.7 follicles per gilt (mean ± SD) that grew to ≥4 mm were identified during the first and second 21-day study periods, respectively (P<0.01). Four follicular waves (defined as the synchronous growth of a group of follicles from 2–3 mm to ≥4 mm) emerged during the first period, and five waves emerged during the second period. The maximum diameters attained by the largest follicles of waves were 5.7 ± 0.6 and 7.0 ± 0.5 mm (first and second periods, respectively; P<0.01). The present results provide direct evidence for the rhythmic, wave-like pattern of antral follicle recruitment in prepubertal gilts. The number of follicles and maximum diameter they attain increase significantly during the expected activation of the hypothalamo-pituitary-ovarian axis in prepubescent gilts.

Comparison of the effects of pretreatment with Veramix sponge (medroxyprogesterone acetate) or CIDR (natural progesterone) in combination with an injection of estradiol-17β on ovarian activity, endocrine profiles, and embryo yields in cyclic ewes superovulated in the multiple-dose Folltropin-V (porcine FSH) regimen

Follicular wave status at the beginning of exogenous FSH administration is an important contributor to variability in superovulatory responses in ruminants. Studies in ewes have shown a decrease in the number of ovulations when superovulation is initiated in the presence of ostensibly ovulatory-sized ovarian follicles. Hormonal ablation of large antral follicles with the progestin-estradiol (E2-17β) treatment significantly reduces this variability in superovulated anestrous ewes, but the effects of the treatment in cycling ewes have not yet been assessed. Sixteen Rideau Arcott × Polled Dorset ewes (November-December) received either medroxyprogesterone acetate (MAP)-releasing intravaginal sponges (60 mg) or controlled internal drug release (CIDR) devices (containing 300 mg of natural progesterone) for 14 days (Days 0-14), with a single intramuscular injection of 350 μg of E2-17β on Day 6. The superovulatory treatment consisted of six injections of porcine FSH (Folltropin-V) given twice daily, followed by a bolus GnRH injection (50 μg intramuscular) on Day 15. There were no differences (P < 0.05) in the ovulatory responses and embryo yields between the two groups of ewes. In both subsets of animals, the next follicular wave emerged ∼2.5 days after an E2-17β injection (P > 0.05). A decline in maximum follicle size after an E2-17β injection was more abrupt in CIDR- compared with MAP-treated animals, and the ewes pretreated with exogenous progesterone had significantly more 3-mm follicles at the start of the superovulatory treatment. The metabolic clearance rate of exogenous E2-17β appeared to be greater in MAP-treated ewes, but circulating concentrations of porcine FSH failed to increase significantly after each Folltropin-V injection in CIDR-treated animals. The CIDR-treated ewes exceeded (P < 0.05) their MAP-treated counterparts in serum E2-17β concentrations during superovulation. In spite of differences in antral follicle numbers and endocrine profiles between MAP- and CIDR-treated cyclic ewes receiving E2-17β before ovarian superstimulation, there were no differences in superovulatory responses.

Factors affecting maternal behaviour and responsiveness in sows during periparturient and lactation periods

Abstract Maternal responsiveness of sows affects piglet survival rate by influencing the economic results of breeding. The purpose of this article was to present the relations among housing environment for sows during periparturient period and lactation, endocrine changes in sows, and maternal behaviour and welfare, which ultimately all affect the productive results. The following welfare-related factors were discussed in this paper: the type of farrowing environment, including the type of pen, the area for free movement or confinement crates, alternative loose-housing systems, the importance of nest building for further nursing, and fear as a factor which can impair productivity. Streszczenie Troskliwość macierzyńska loch wpływa na przeżywalność prosiąt determinując wyniki ekonomiczne chowu świń. Celem niniejszego opracowania jest przedstawienie interakcji pomiędzy systemem utrzymania loch w okresie okołoporodowym i laktacji, a zmianami hormonalnymi występującymi u macior w tym czasie oraz ich łączne oddziaływanie na zachowanie loch i poziom ich dobrostanu, które w efekcie kształtują uzyskiwane wyniki produkcyjne. Pod uwagę wzięto następujące czynniki warunkujące poziom dobrostanu loch w okresie okołoporodowym: rodzaj kojca porodowego, powierzchnię kojca, w tym wpływ systemów uniemożliwiających losze swobodę poruszania się, jak również systemy otwarte, alternatywne. Omówiono również istotność budowy gniazda dla dalszego przebiegu odchowu prosiąt, jak również strach przed obsługą, który może zniweczyć wysiłki w kierunku uzyskiwania lepszych wyników produkcyjnych w postaci większej liczby prosiąt odchowanych.

The utility of nanowater for ram semen cryopreservation

Nanowater (NW; water declusterized in the low-temperature plasma reactor) has specific physicochemical properties that could increase semen viability after freezing and hence fertility after artificial insemination (AI) procedures. The main goal of this study was to evaluate ram semen quality after freezing in the media containing NW. Ejaculates from 10 rams were divided into two equal parts, diluted in a commercially available semen extender (Triladyl®; MiniTüb GmbH, Tiefenbach, Germany) prepared with deionized water (DW) or NW, and then frozen in liquid nitrogen. Semen samples were examined for sperm motility and morphology using the sperm class analyzer system and light microscopy. Cryo-scanning electron microscopy (cryo-SEM) was employed to determine the size of extracellular water crystals in frozen semen samples. Survival time at room temperature, aspartate aminotransferase (AspAT) and alkaline phosphatase (ALP) concentrations post-thawing as well as conception/lambing rates after laparoscopic intrauterine AI of 120 ewes were also determined. There were no significant differences between DW and NW groups in sperm progressive motility (26.4 ± 12.2 and 30.8 ± 12.4%) or survival time (266.6 ± 61.3 and 270.9 ± 76.7 min) after thawing and no differences in the percentages of spermatozoa with various morphological defects before or after freezing. There were, however, differences (P < 0.05) in AspAT (DW: 187.1 ± 160.4 vs. NW: 152.7 ± 118.3 U/l) and ALP concentrations (DW: 2198.3 ± 1810.5 vs. NW: 1612.1 ± 1144.8 U/l) in semen samples post-thawing. Extracellular water crystals were larger (P < 0.05) in ejaculates frozen in NW-containing media. Ultrasonographic examinations on day 40 post-AI revealed higher (P < 0.05) conception rates in ewes inseminated with NW (78.3%) compared with DW semen (58.3%), and the percentages of ewes that carried lambs to term were 73.3% and 45.0% in NW and DW groups, respectively (P < 0.01). In summary, the use of a semen extender prepared with NW was associated with a substantial improvement in the fertilizing ability of frozen-thawed ram semen and lamb productivity of inseminated ewes.