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The main problem in dairy herds is reproductive disorders, which are influenced by many factors, including temperature. Heat stress reduces the quality of oocytes and their maturation through the influence of, e.g., mitochondrial function. Mitochondria are crucial during oocyte maturation as well as the process of fertilization and embryonic development. Disturbances related to high temperature will be increasingly observed due to global warming. In present studies, we have proven that exposure to high temperatures during the cleaving of embryos statistically significantly (at the level of p < 0.01) reduces the percentage of oocytes that cleaved and developed into blastocysts eight days after insemination. The study showed the highest percentage of embryos that underwent division in the control group (38.3 °C). The value was 88.10 ± 6.20%, while the lowest was obtained in the study group at 41.0 °C (52.32 ± 8.40%). It was also shown that high temperature has a statistically significant (p < 0.01) effect on the percentage of embryos that developed from the one-cell stage to blastocysts. The study showed that exposure to a temperature of 41.0 °C significantly reduced the percentage of embryos that split relative to the control group (38.3 °C; 88.10 ± 6.20%). Moreover, it was noted that the highest tested temperature limits the development of oocytes to the blastocyst stage by 5.00 ± 9.12% compared to controls (33.33 ± 7.10%) and cleaved embryos to blastocysts by 3.52 ± 6.80%; the control was 39.47 ± 5.40%. There was also a highly significant (p < 0.0001) effect of temperature on cytoplasmic ROS levels after 6 and 12 h IVM. The highest level of mitochondrial ROS was found in the group of oocytes after 6 h IVM at 41.0 °C and the lowest was found in the control group. In turn, at 41.0 °C after 12 h of IVM, the mitochondrial ROS level had a 2.00 fluorescent ratio, and the lowest in the group was 38.3 °C (1.08). Moreover, with increasing temperature, a decrease in the expression level of both LC3 and SIRT1 protein markers was observed. It was proved that the autophagy process was impaired as a result of high temperature. Understanding of the cellular and molecular responses of oocytes to elevated temperatures will be helpful in the development of heat resistance strategies in dairy cattle.

Endocrine-disrupting chemicals (EDCs) are common in the environment and in everyday products such as cosmetics, plastic food packaging, and medicines. These substances are toxic in small doses (even in the order of micrograms) and enter the body through the skin, digestive or respiratory system. Numerous studies confirm the negative impact of EDCs on living organisms. They disrupt endocrine functions, contributing to the development of neoplastic and neurological diseases, as well as problems with the circulatory system and reproduction. EDCs affect humans and animals by modulating epigenetic processes that can lead to disturbances in gene expression or failure and even death. They also affect steroid hormones by binding to their receptors as well as interfering with synthesis and secretion of hormones. Prenatal exposure may be related to the impact of EDCs on offspring, resulting in effects of these substances on the ovaries and leading to the reduction of fertility through disturbances in the function of steroid receptors or problems with steroidogenesis and gametogenesis. Current literature indicates the need to continue research on the effects of EDCs on the female reproductive system. The aim of this review was to identify the effects of endocrine-disrupting chemicals on the female reproductive system and their genetic effects based on recent literature.

This review searches for and analyzes existing knowledge on horse tooth anatomy in terms of evolutionary and morphological changes, feeding habits, breeding practices, and welfare. More than 150 articles from relevant databases were analyzed, taking into account the issues of our experimental research on the ultrastructure of Equidae tooth enamel. After our analysis, the knowledge on this subject accumulated up in the past, almost 50 years has been logically arranged into three basic directions: evolutionary-palaeontological, morpho-functional, and dentistic, which is also demonstrated by the latest trends in the study of enamel morphology and in the practice of equine dentistry. The obtained data show that in recent years we have observed a rapid increase in publications and a thematic expansion of the scope of research. It is caused by the need to deepen knowledge in theory and in the practice of feeding species in nature and in captivity as well as the possibility of using new technical resources to improve the excellence of such research. It is a summary of the knowledge of a certain stage of equine tooth enamel studies for this period of time, which serves as the basis for our experimental research (the materials are prepared for publication) and at the same time, defines research perspectives for the next stage of development.

Simple Summary Heavy metal pollution is common in the environment and can come from natural sources such as forest fires and volcanic eruptions, as well as from anthropogenic sources: mines, smelters, or refineries. These elements are toxic to living organisms and internal organs and can accumulate in living organisms. They can negatively affect both female and male fertility. Chronic exposure of cattle to toxic metals can cause embryotoxicity, disturbances in spermatogenesis, and oocyte development. It is important to monitor environmental pollution with toxic metals. Abstract The aim of this review is to comprehensively present disorders of the reproductive system in cattle exposed to contact with toxic metals. Toxic metals are a common environmental pollutant and can come from mines, smelters, fossil fuel combustion, or volcanic eruptions. Metals have the ability to bioaccumulate in living organisms, thus contaminating the food chain and may pose a threat to humans. They accumulate mainly in the liver and kidneys, but also in muscles and fat tissue. Toxic metals such as lead (Pb), arsenic (As), mercury (Hg), and cadmium (Cd) have a negative impact on the fertility of animals; they can lead to abortions, premature calving, or oocyte dysfunction. Moreover, in the male reproductive system, they disrupt spermatogenesis, and cause apoptosis of sperm and oxidative damage. The main source of exposure of livestock to toxic metals is through the consumption of feed or contaminated water. It is important to monitor the level of heavy metals in animal products to prevent human poisoning. Toxic metal biomonitoring can be performed by testing urine, blood, milk, plasma, or hair. Chromium (Cr), arsenic (As), and cadmium (Cd) are excreted in the urine, while lead can be detected by examining the blood of animals, while in milk, arsenic (As), cadmium (Cd), nickel (Ni), and lead (Pb) can be detected. Moreover, toxic metals do not biodegrade in the environment. To purify soil and waters, remediation methods, e.g., biological or chemical, should be used.

The aim of the study was to compare the levels of selected blood parameters of dairy cattle in an area with copper industry (LGOM, area I, n = 21) and the Wroclaw agricultural suburban area (area II, n = 20). The concentration of heavy metals Cd, Cu, Pb and Zn (atomic absorption spectrometry method) and Hg (spectrometric method) was analysed in full blood. However, other parameters were determined in the blood serum: Ca, P (inorganic), Mg and Fe (photometric method), aspartate aminotransferase (AST) – an enzyme test in accordance with the recommendations of the IFCC, lactate dehydrogenase (LDH) – the test optimized according to the guidelines DGKC, gamma-glutamyl transferase (GGT) – kinetic photometric test. Biochemical parameters in blood serum were determined with the use of an automatic biochemical analyser type Pentra 400 and reagents of Horiba ABX (France). Furthermore, the analysis covered: the total antioxidant capacity (TAS) – colorimetric assay based on the ABTS and peroxidase reaction as well as the activity of glutathione reductase (GR) – colorimetric test based on the reduction of glutathione (GSSG) in the presence of NADPH. These parameters were determined with the use of the same analyser and commercial assays kit of Randox company. The Cd concentration in both areas was very low and did not exceed 1.65 µg/l, while the Pb concentration in the LGOM region was 0.021 mg/l and 0.031 mg/l in area II. The level of mercury in area I in both regions was similar (about 0.03 µg/l). The copper content was significantly higher in area I than in region II (1.67 mgl/l and 0.72 mg/l respectively), which indicates the possibility of industry impact on copper accumulation in cows. The Zn concentration was significantly lower in the LGOM region than in area II (2.50 mg/l) in contrast to Cu. The AST activity was significantly lower in area I (66.56 U/l) than in area II (75.49 U/l). Similar findings were reported with GGT activity (lower concentration in area I – 21.42 U/l). The LDH levels in animals were similar in both areas (2015.0 and 1976.2 U/l respectively), as were TAS (1.12 and 1.16 mmol/l) and GR (422.4 and 429.3 U/l). Mean activity of AST and GGT in cows were present in both areas, reaching ranges of the reference values, but the activity of LDH was significantly higher. There are no reference values for TAS and GR. Similar concentrations of Ca, Mg and Fe were noticed in both regions during the study, while the content of P was significantly higher in area I. The mean concentration of detected macroelements were in the reference ranges. The analysis proved that the cooper industry does not negatively affect the content of biochemical parameters in the blood of dairy cows.

African Swine Fever (ASF) is a highly contagious disease that affects the domestic pig and wild boar population. The aim of this study was to describe the introduction and spread of the ASF virus in Western Europe (1960–1995) and in Eastern Europe (2007–2018), with particular emphasis on the current ASF situation in Poland and its challenges and future perspectives. The first ASF outbreak in Europe was reported in Portugal in 1957, with the virus spreading over most of Western Europe over the next 30 years. In Eastern Europe, the virus was first observed in Georgia in 2007, from where the disease spread quickly to other neighboring countries, reaching Poland in 2014. Since then, there have been 3341 confirmed cases in the wild boar population in Poland. Although there have been no confirmed cases of wild boars coming into contact with domestic pigs, the first notified case concerning domestic pigs was reported in July 2014. Since then, there have been a total of 213 confirmed outbreaks of ASF on Polish pig farms. Given the virulence of the ASF virus and the myriad of transmission routes across Europe, the monitoring of this disease must be a priority for Europe.

The aim of this study was to assess the influence of horse, saddle, and rider on saddle fit in racehorses by detecting pressure distribution using infrared thermography. In this study, 22 saddles used on 65 racing horses ridden by 21 riders were used. Data from horses including gender, breed, age, training intensity, and level of performance were collected. Type and mass of the saddle were also obtained, along with information about the rider's body mass and riding skills. Thermographic images of the saddle's panels were captured immediately after untacking the horse at each thermographic examination. On each thermographic image of the saddle panels, six regions of interest (ROIs) were marked, with mean temperature calculated within each ROI to indicate pressure distribution. Saddle fit was evaluated for right/left panel pressure, bridging/rocking pressure, and front/back pressure according to horse's: gender, breed, age, training intensity, level of conditioning, rider's skills, and load (saddle plus rider mass). There were statistically significant relationships (P < .05) between left/right asymmetry and age, training, intensity and load. In front/back pressure, there was a statistically significant relationship (P < .05) for load. No statistically significant relationships were observed between bridging/rocking pressure and the rest of the aforementioned variables. The study indicated that load, horse age, and training intensity influence pressure distribution in racing saddles. Therefore, animal age and load have to be considered in saddle fit. Infrared thermography has been confirmed as a useful tool in the evaluation of saddle fit in racing horses.

Dehorning of cattle is painful, but remains a commonly performed procedure in horned breeds as it reduces injuries from social contact and especially improves safety for stock-persons. Dehorned cattle also require less space during feeding or transport. To date a large proportion of cattle is disbudded or dehorned and in most cases without proper pain relief. Understanding and recognizing the signs and factors causing pain in farm animals is an area that has been continually developing.

This paper presents the physiological activity of the cerebral cortex in sheep in electroencephalographic findings. The study was performed to evaluate and improve understanding of brain monitoring methods in freely moving animals without the use of any anaesthetic methods during the acquisition stage. The aim of the study was to determine the physiological activity of the cerebral cortex in animals in a sheep model (using clinically healthy Polish Merino rams, aged 1 yr.) to determine its clinical EEG protocol. The EEG was registered using an in-lab EEG device as well as ambulatory systems (Holter EEG). The bioelectrical activity of the sheep cerebral cortex was recorded using gold disc and needle electrodes placed on experimentally determined locations on the scalp. The main finding of this study was the rhythmic EEG activity of the sheep brain in wakeful and conscious states (eyes open). The rhythm was bilaterally synchronous and determined a basic pattern in the registration of physiological activity of the cerebral cortex. The acquired rhythm may correspond to the theta rhythm in humans, which is a normal activity controlled by the hippocampus. This background activity comprised intermittent episodic slow waves and synchronous beta waves.

Fifteen sheep where placed in climatic chamber and exposed to a high temperature (30°C). Then, the air movement was induced in order to examine its soothing effect on heat stress. The physiological reactions like respiratory and heart rates, as well as the morphologic, biochemical parameters and cortisol levels in blood were examined. It was found that under heat stress conditions, the respiratory rate increased up to 96.43 breaths/min, heart rate up to 107.79 beats/min, and white blood cells count decreased to 9.12 k/μL. The increased level of potassium, chlorine, and calcium was also observed. The increased air movement resulted in thermal stress soothing. A decrease in respiratory rate, heart rate, and cortisol concentration was observed. The study demonstrated that heat stress leads to serious changes in physiological and blood parameters in sheep but this effect can be minimised by air movement.