The Effect of Season and Meteorological Conditions on Parasite Infection in Farm-Maintained Mouflons (Ovis aries Musimon).

Due to their limited environment, farm animals are at greater risk of parasitic infection than free-living animals, which also have greater natural resistance to parasitic diseases. The aim of the present study was to determine the influence of season and meteorological conditions (temperature and humidity) on the species composition and dynamics of parasitic infections in farmed mouflons. The study was conducted in a herd of mouflon (n = 40) in an extensive system: the animals remained on pasture all year round. The herd was dewormed twice per year with albendazole. Fecal samples were collected at monthly intervals over three years and tested. The prevalence of infection was defined based on coproscopic methods. For most of the studied protozoans (except for E. parva), a greater prevalence was recorded in spring and summer (i.w. from May to September). Regarding nematodes, Capillaria spp., Nematodirus sp., and the Trichostrongylidae demonstrated a much greater prevalence in winter (i.e., in January and December). Temperature and precipitation were found to be positively correlated with intensity of infection by protozoans. However, maximum air temperature was negatively correlated with infection intensity by some nematodes. The deworming practice used in the herd (selection of substance, date, and method of dosing) did not effectively protect the mouflons against parasitoses. Changes in the microclimate resulted in high extent and intensity of mouflon infection with gastrointestinal parasites. Understanding the dynamics of parasitic infections in mouflons during the year allows the development of an appropriate preventive programme.

Bacterial Contamination of Boar Semen and its Relationship to Sperm Quality Preserved in Commercial Extender Containing Gentamicin Sulfate.

This study was designed to determine the degree and type of bacterial contamination in boar semen (79 ejaculates from Large White and Landrace boars) and its consequences for sperm quality during storage (27 extended semen samples, 16°C for five days) under practical conditions of artificial insemination (AI). The results revealed the presence of aerobic bacteria in 99% of the ejaculates (from 80 to 370 ×106 colony-forming units/mL). Most of the ejaculates contained two or three bacterial contaminants, while the Staphylococcus, Streptococcus, and Pseudomonas bacterial genera were most frequently isolated. Also detected were Enterobacter spp., Bacillus spp., Proteus spp., Escherichia coli, P. fluorescens, and P. aeruginosa. In general, the growth of certain bacterial types isolated prior to semen processing (Enterobacter spp., E. coli, P. fluorescens, and P. aeruginosa) was not discovered on different days of storage, but fluctuations (with a tendency towards increases) were found in the frequencies of Bacillus spp., Pseudomonas spp., and Staphylococcus spp. isolates up to the end of storage. Semen preserved for five days exhibited decreases in sperm motility and increases in the average number of total aerobic bacteria; this was associated with sperm agglutination, plasma membrane disruption, and acrosome damage. We inferred that, due to the different degrees and types of bacterial contaminants in the boar ejaculates, the inhibitory activity of some antimicrobial agents used in swine extenders (such as gentamicin sulfate) may be limited. Because such agents can contribute to the overgrowth of certain aerobic bacteria and a reduction in the quality of stored semen, procedures with high standards of hygiene and microbiological control should be used when processing boar semen.

Circannual changes in serum concentrations of thyroxine, calcitonin and parathormone in immature and mature red deer females (Cervus elaphus).

The aim of this study was to determine circannual changes in the serum concentrations of thyroxine, calcitonin and parathormone in mature and immature red deer females. Blood samples from 8 hinds were collected monthly for 26 months. Secretions of thyroxine and calcitonin showed circannual rhythms with significantly higher levels in the immature hinds compared to the mature animals (p<0.05). For thyroxine, the concentration was higher in the winter/spring period than in summer/autumn (p<0.05), while for calcitonin the concentration profile was the opposite (p<0.05). The concentration of parathormone was significantly higher in summer/autumn that in the other months of the experiment (p<0.01). These results may indicate that the hormones investigated may be involved in the regulation of seasonal reproductive activity and in processes contributing to entering puberty in red deer females.

Analysis of Annual Changes in the Concentrations of Selected Macro- and Microelements, Thyroxine, and Testosterone in the Serum of Red Deer (Cervus elaphus) Stags.

The aim of the study was to analyze seasonal changes in the concentrations of calcium, phosphorus, magnesium, and selenium as well as thyroxine and testosterone in adult red deer stags. The highest testosterone concentrations (mean 6.29±4.36 ng/ml) were observed from the end of August to November, confirming an increase in testicular secretory activity during the mating season. The changes in thyroxine concentration show circannual rhythms, most likely related to changes in the air temperature. The highest mean level of thyroxine was observed in spring (55.69±10.99 ng/ml). The concentration of selenium also reached the highest level during this season (0.107±0.027 µg/ml). In the case of the studied macroelements, the concentrations were stable from spring to summer but then decreased to the lowest mean values in autumn in both years of the experiment (Ca, 61.17±10.60; P, 47.08±9.59; Mg, 15.96±2.39 µg/ml). The dynamics of thyroxine secretion does not seem to affect directly the metabolism of calcium, phosphorus, and magnesium. In turn, sexual activity, manifested in the increase in secretion of testosterone, may affect changes in the concentration of calcium. Additionally, we cannot exclude a connection between changes in the concentrations of testosterone and selenium.

Serum selenium concentration and glutathione peroxidase activity and selenium content in testes of Polish Konik horses from selenium--deficient area in North-Western Poland.

The aim of this study was to determine serum selenium concentrations in Polish Konik horses residing in the Odra Delta Nature Park (Poland) and to evaluate the activity of glutathione peroxidase and Se content in testes of this horse breed. In over 95% of cases, serum Se concentration was below the optimal range, and none of the horses examined was deficient in this trace element. The lack of Se deficiency in the animals examined suggests however, that the Polish Konik horses have a natural ability to the optimal use of nutrients available in their life area. Testicular content of Se and GSHPx activity in the colts was higher than those found in stallions, and a positive relationship between these antioxidants was demonstrated. The differences in Se contents and GSHPx activities in testes between colts and stallions suggest that selenoenzymes play important roles during the puberty of male horses.

A study on the occurrence of polyovular follicles in porcine ovaries with particular reference to intrafollicular hormone concentrations, quality of oocytes and their in vitro fertilization.

The aim of this study was to identify the occurrence of polyovular follicles in porcine ovaries. We investigated the presence of such follicles in relation to age, and compared the intrafollicular concentrations of steroid hormones between poly- and uniovular follicles. Then we measured the size, viability and the in vitro fertilizing ability of the oocytes from polyovular follicles. Histological examinations documented the occurrence of polyovular follicles in pigs at various stages of follicular growth. Within antral follicles, the number of polyovular follicles was higher in the ovaries of gilts than in sows (P < 0.01). We noticed differences in the viability and size of oocytes recovered from the same follicles. We noted a higher concentration of oestradiol-17beta and a lower concentration of progesterone in polyovular follicles as compared with uniovular follicles (P < 0.01). The amount of embryos after in vitro-fertilization of oocytes from polyovular follicles was significantly lower than that from uniovular ones. Nevertheless, we found that some oocytes from polyovular follicles also have the capacity to be fertilized in vitro and be developed to the blastocyst stage.

Selenium status and GSH-Px activity in semen and blood of boars at different ages used for artificial insemination.

This study was performed to determine the relationship between selenium (Se) content and Se-dependent glutathione peroxidase (GSH-Px) activity in blood and semen, and semen quality of boars at different age used in an artificial insemination (AI) station. Routine macroscopic and microscopic analyses of semen quality were accompanied by measurement of Se content and GSH-Px activity in blood and semen. The Se concentration in blood plasma, seminal fluid and spermatozoa was measured by fluorometric method, the GSH-Px activity by a method based on NADPH-coupled reaction. A total of 155 ejaculates and 58 blood samples were investigated. The results of this study showed that there was no direct relationship between the Se content and GSH-Px activity in blood plasma and semen, and semen quality of sexual matured boars. The mechanisms controlling Se content and GSH-Px activity in blood and semen seem to be independent. The age of boars as a differentiating factor for Se content and GSH-Px activity in blood and semen is possible. It is concluded that a determination of Se status and/or GSH-Px activity in organism before Se supplementation is indicated.

Ultrastructure of the ram pinealocytes during breeding season in natural short and in artificial long photoperiods.

The study was performed from 20th September to 20th October on eight Polish Longwool rams, variety Pomorska (Pomeranian), aged 33 months, which were divided into two equal groups. The animals of control group were kept in natural photoperiod. The experimental group was maintained during 30 days in controlled lighting conditions (16L: 8D). On the thirtieth day of the experiment the animals were slaughtered between 1000h and 1200h. The pineal glands were prepared for EM. Point count analysis was employed to estimate the relative volumes of pinealocyte organelles. The increase of relative volumes of mitochondria and lipid droplets in comparison to the control was observed in the experimental group. There were also some qualitative changes in organization of granular endoplasmic reticulum and microtubules.