Volume 13 (2013): Issue 2 (March 2013)

In this review paper we focused on the metabolism of arachidonic acid (AA), an n-6 fatty acid. It can be metabolized to many compounds having a broad effect in the body. Their homeostasis and human health depend on the ratio of dietary n-6 to n-3 fatty acids. These compounds, taken together with the products of animal origin and vegetables should be better balanced in the human diet. This can be achieved by reducing arachidonic acid and its precursors through a diet that modifies the content of AA in animal products such as eggs, milk and meat

The hypothalamus synthesizes molecules involved in the regulation of feeding behaviour. Nesfatin- 1 is a recently discovered substance expressed in both the brain and peripheral tissues and exerts a strong anorectic action. Nesfatin-1-immunoreactive cell bodies are distributed in arcuate (ARC), paraventricular (PVN) and supraoptic (SON) nuclei, where the peptide has been found to be co-expressed with pro-opiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART), oxytocin (OX) and vasopressin (VP). More detailed studies have shown a wide distribution of nesfatin-1-positive neurons in several brain areas, such as the forebrain, hindbrain, brainstem and spinal cord. Moreover, nesfatin-1 has been also expressed in peripheral tissues, colocalizing with ghrelin in the gastric mucosa and insulin in β-cells of the endocrine pancreas and adipose tissue. Functional studies have revealed that exogenous nesfatin-1 administered into the brain ventricles, subcutaneously or intraperitoneally, was able to decrease both food intake in the dark phase as well as body weight gain in a dose-dependent manner. In addition, recent findings suggest the involvement of nesfatin-1 in the control of insulin secretion as well as immune and stress-related responses. However, since there is still a deficiency of data concerning the nesfatin-1 receptor, the possible implementation of nesfatin-1 analogs during human metabolic disorders requires further study.

In pigs, creatine is synthesized mainly in the liver, kidneys and pancreas from amino acids such as glycine, arginine and methionine. It is located mainly in skeletal muscle (approximately 95-98%) in the form of phosphocreatine. It is a source of energy for muscles, thus delaying the postmortem metabolism of glycogen and lactate formation and a decrease in pH during conversion of muscle to meat. Use of supplemental creatine monohydrate in pig feed may contribute to the improvement of pork quality parameters such as pH, colour, water holding capacity and drip loss. These parameters are also improved in pigs carrying the RN- and RYR1T gene. Creatine contained in meat can also be a precursor of heterocyclic aromatic amines mutagenic to humans, formed during thermal processing of meat.

The paper describes a review of alternative methods of horse parasite control. Horses serve as hosts for a wide array of parasites, among which strongylid nematodes (Strongylidae) constitute considerable pathogens. Due to the short and monoxenous life cycle of these parasites and also the resistance to benzimidazole and other drugs, the control strategies are often ineffective. Thus, the treatment of strongylids constitutes a priority aiming at the improvement of animal welfare, with special attention paid to the stable and pasture organization. The treatment carried out in the stable should consider the frequent exchange of horse bedding at regular time intervals, periodic disinfection of stalls and maximum limitation of contact of feed and water with the stable substratum. An application of feed supplements, i.e. plants or plant extracts, which act as natural dewormers, also constitutes an important factor in the control of parasitic infections. Among the treatments applied to the pasture, the regular removal of waste, quarter pasturing, as well as an alternate pasturing with other animal species, are of special importance. The use of deworming properties of fungi, which constitute a natural component of green growth in pasture, seems to be the next method of nematode control, already confirmed by several studies.

The genotyping efficiency and polymorphism of 7 microsatellite markers (AHT084, COR006, COR017, COR018, COR040, COR055, COR088) was evaluated in order to apply them to parentage testing among a number of warm-blooded, cold-blooded and primitive horse breeds and to illustrate genetic differences between the breeds investigated. The amplification and sequence structure of these STR markers was also verified in other Equidae like zebra, kulan, donkey and Przewalski horse. Microsatellite allelic differentiation was similar to the allele numbers reported, with an extremely wide allelic range observed at AHT084 locus. However, due to genotyping difficulties AHT084 is not a suitable marker for parentage testing. The use of the other 6 STR markers among most of the horse breeds studied allows excluding wrongly assigned parentage with a probability of 0.99. Fragment analysis and sequencing of STR alleles confirmed the presence of investigated tandem repeats in other Equidae species. Clustering of investigated horse breeds on the tree of Fst distance was consistent with their breeding history, clearly separating breeds into 3 horse types mentioned above.

The aim of the study was to find osteopontin gene (OPN) polymorphisms as potential mutations affecting the expression level of genes in the ovaries, uterus and oviduct of sows. The material consisted of 71 F1 sows (Polish Large White × Polish Landrace). In the first stage several polymorphisms in the promoter region, intron 6, exon 6 and 7 of the OPN gene were found. The parameters estimated were the frequency of alleles and genotypes, observed heterozygosity and gene diversity, PIC, and chi2 factors. Chi2 values allow for assessment of genetic equilibrium in the population. Thus, the loci OPNp3-4 and OPNe6-1 were in genetic disequilibrium while locus OPNe6-Knoll showed genetic equilibrium. Also real-time PCR analysis to determine the expression dynamics of the OPN gene in examined tissues was performed in relation to “housekeeping” genes. A comparison was made for relative expression in different tissues and different mutations. The highest expression pattern was observed in the oviduct. Based on the novel polymorphisms a significant correlation between the OPN genotype and OPN expression (mRNA) level in the ovary, oviduct, uterine body and uterine horn was observed. In the second stage, the levels of expression of the OPN gene in individual tissues, traits of reproductive performance and reproductive tract traits of sows were also compared. The expression levels in the uterine body and oviduct were related to the age of mating, cervical length, litter weight at birth, number of active nipples, age at slaughter and body weight at mating.

Analyses were conducted on pedigrees of 845 animals registered at the Hovawart Club in Poland (113 dogs and their ancestors). The degree of inbreeding was calculated for the whole population (0.0026) and separately for male dogs (0.0021) and bitches (0.0031), and the coefficient of mean relationship was calculated for the entire population (0.0064), among male dogs (0.0064), among females (0.0073) and between males and females (0.0061). The inbreeding and relationship coefficients obtained are lower than those estimated for Polish populations of other dog breeds. The calculated effective number of founders (268) and ancestors (233) may indicate rather low genetic diversity. Preferences of breeders concerning coat colour were discussed. Black and tan coat dogs dominated at first, followed by blond ones, and over the last five of the analysed years black coat dogs emerged.

The first aim of the present study was to evaluate whether the trainer factor and the sex of the horse affect the heart rate (HR) of the trainer-horse pair. The second aim was to estimate the level of the trainer-horse pair’s emotions and to find the relationship of the HR between the trainer and the horse during the preliminary, natural-method training. The animals used in the study were 40 three-year-old purebred Arabian horses trained by two trainers from the Silversand Horsemanship School. Each trainer worked with 20 randomly selected horses, equally grouped by sex. The study was carried out during the first day of the training cycle. The aim was to have a horse accept a rider. The following items were subject to analysis: deconcentration, concentration, desensitizing, putting on the lungeing surcingle, and saddling. The emotional status of the horses and the trainers was evaluated based on HR variations which were measured by applying Polar S810 telemetric devices. The device produced continuous measurements with readings every 60 seconds. Two-factor analysis of variance and Pearson correlations were determined with the use of SAS software. Significance of differences between mean values was verified using Tukey’s test. The results obtained revealed that the sex of the trained horses was not an important factor in the evaluation of trainer’s emotions, despite the fact that fillies were characterized as having a more uniform HR. The trainer is very responsible for the emotions of a trained horse, especially at the beginning of training and during saddling. From a trainer’s point of view, it is important to complete the horse concentration task as quickly as possible. The lack of an emotional relationship in the trainer-horse pair during some training elements, suggests that it is not only the trainer’s experience, but mainly the trainer’s personality that determines the probable success in naturalmethod work.

Somatic cell cloning efficiency is determined by many factors. One of the most important factors is the structure-functional quality of nuclear donor cells. Morphologic criteria that have been used to date for qualitative evaluation of somatic cells may be insufficient for practical application in the cloning. Biochemical and biophysical changes that are one of the earliest symptoms in the transduction of apoptotic signal may be not reflected in the morphologic changes of somatic cells. For this reason, adult cutaneous or foetal fibroblast cells that, in our experiments, provided the source of genomic DNA for the cloning procedure had been previously analysed for biochemical and biophysical proapoptotic alterations with the use of live-DNA (YO-PRO-1) and plasma membrane (Annexin V-eGFP) fluorescent markers. In Groups IA and IB, the generation of nucleartransferred (NT) embryos using non-apoptotic/non-necrotic contact-inhibited or serum-starved adult cutaneous fibroblast cells yielded the morula and blastocyst formation rates of 125/231 (54.1%) and 68/231 (29.4%) or 99/237 (41.8%) and 43/237 (18.1%), respectively. In Groups IIA and IIB, the frequencies of embryos reconstituted with non-apoptotic/non-necrotic contact-inhibited or serum-starved foetal fibroblast cell nuclei that reached the morula and blastocyst stages were 171/245 (69.8%) and 97/245 (39.6%) or 132/227 (58.1%) and 63/227 (27.8%), respectively. In conclusion, contact inhibition of migration and proliferative activity among the subpopulations of adult dermal fibroblast cells and foetal fibroblast cells resulted in considerably higher morula and blastocyst formation rates of in vitro cultured cloned pig embryos compared to serum starvation of either type of fibroblast cell line. Moreover, irrespective of the methods applied to artificially synchronize the mitotic cycle of nuclear donor cells at the G0/G1 phases, developmental abilities to reach the morula/blastocyst stages were significantly higher for porcine NT embryos that had been reconstructed with non-apoptotic/non-necrotic foetal fibroblast cells than those for NT embryos that had been reconstructed with non-apoptotic/non-necrotic adult dermal fibroblast cells. To our knowledge, the generation of cloned pig embryos using abattoir-derived oocytes receiving cell nuclei descended from contact-inhibited or serum-deprived somatic cells undergoing comprehensive vital diagnostics for the absence of biochemical and biophysical proapoptotic alterations within their plasmalemmas has not been reported so far.

Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans. Because of this characteristic influence, the aim of this investigation was to examine the effect of genistein and daidzein on testicular weight and testosterone secretion in ISA Brown roosters. Genistein and daidzein as non-steroid phytoestrogens were added in large amounts to the feed of roosters. Soy isoflavones were added to rooster diets in amounts of 0, 300, 600, 1200 and 1800 mg/kg of feed. At the end of the 37th week no significant differences were found between the groups in testicular weight (P>0.05) and testosterone secretion (P>0.05) measured in the blood of birds. Blood testosterone concentration was significantly higher in younger (20-week-old) roosters than in 37-weekold roosters (P<0.01). Genistein and daidzein present in the feed did not influence the weight of testes and no significant differences were found. Further studies are required to investigate the effect of isoflavones on other androgenic characteristics.

A total of 300 growing-finishing pigs (30-110 kg BW), the offspring of Naima sows and Duroc boars, were allocated to three dietary treatments (five pens per treatment, 10 males and 10 females per pen). The growth performance of pigs was determined, and the apparent digestibility of nutrients and energy in animals fed grower diets was calculated by the simple balance method. Complete diets with a high content of triticale (70%-73%) and barley (6.8%-12%) were supplemented with endo-1,4-beta-xylanase (6200 EPU per g). The minimum xylanase activity per kg feed was 1050 and 1500 EPU. Xylanase, at activity levels of 1050 and 1500 EPU kg-1 complete diet, significantly (P≤0.05) increased the apparent digestibility of total protein and highly significantly (P≤0.01) that of crude fat. No significant differences in the digestibility of N-free extractives and energy were found between groups. The increased activity of xylanase (1500 EPU kg^-1 feed) contributed to an increase in the digestibility of dry matter, crude fibre (P≤0.05) and organic matter (P≤0.01), compared with the control group. Higher (P≤0.01) daily gains and average final body weights were noted in pigs fed diets supplemented with the mono-enzyme preparation. The feed conversion ratio (FCR) tended to improve in pigs receiving xylanase-supplemented diets, but the observed differences were statistically non-significant.

The effect of corn distillers dried grains with solubles (DDGS), used in grower-finisher diets with or without supplemental enzymes, on growth performance and carcass and meat quality was determined in an experiment with 48 pigs. Group I (control) received a standard grain-soybean meal mixture without DDGS and without enzymes; Group II was fed a mixture containing 15% (grower) or 20% (finisher) of corn DDGS but without the enzymes; Group III received a mixture containing 15% (grower) or 20% (finisher) of corn DDGS with NSP-hydrolyzing enzymes (200 g t-1). The feed mixtures were isonitrogenous and isoenergetic. All pigs were fattened from 30 to 112 kg. At the end of the experiment all pigs were slaughtered, right carcass sides were evaluated and samples of longissimus muscle were taken for analysis. Inclusion of corn DDGS did not significantly affect pig fattening results and meat quality. The addition of NSP-hydrolyzing enzymes to feed mixtures containing corn DDGS tended to positively influence pig performance. The carcasses of pigs receiving the diet with corn DDGS and NSP-hydrolyzing enzymes were characterized by thinner backfat and greater weight of the primal cuts.

The objective of the study was to test the hypothesis that eggs from native breed laying hens fed a diet containing increased amounts of local feed materials are not inferior in quality to eggs from laying hens receiving a standard diet but raised without outdoor access. The study involved Greenleg Partridge (Z-11) and Rhode Island Red hens (R-11). Within each breed, the control group (C) consisted of 60 hens kept on litter without outdoor access, stocked at 5 birds/m2 and fed a diet containing 65.3% of local feed materials. The experimental group (E) contained 60 layers maintained on litter with access to an outdoor area (11 m2 per bird) and fed a diet containing 77.1% of local feed materials. Eggs from hens of both breeds, which received diets containing increased proportions of local feed materials had lower weight but higher yolk percentage. The quality of eggshells from hens fed the diet with increased amounts of local materials was similar to that of eggshells from confined hens. Egg yolk lipids from experimental groups were characterized by a more beneficial n-6/n-3 acid ratio and elevated vitamin A levels. These eggs had better sensory scores for colour, flavour and aroma, which suggests that it is appropriate to raise native breeds of chickens with outdoor access and local feed materials can be used in extensive husbandry systems.

The aim of the study was to determine the degree to which different whole milk feeding systems according to ecological standards affect the results of rearing, some blood biochemical and haematological parameters, and health status of Polish Holstein-Friesian calves. The experiment was conducted from birth to 150 days of age with 32 calves (16 heifer and 16 bull calves), assigned to four analogous groups (8 animals: 4 ♀ and 4 ♂ per group). In group I, calves suckled colostrum (ad

libitum) and mother’s milk from 5 to 90 days of age (twice daily for 30 minutes); in group II, they suckled colostrum (ad libitum), mother’s milk from 5 to 42 days of age (twice daily for 30 minutes), and received milk from nipple buckets (6 l twice daily) from 43 to 90 days of age; in groups III and IV calves received from nipple buckets a limited amount of colostrum (4.5-6 l/day) and milk (on average 5.82 and 4.82 l/day, respectively). Feeding limited whole milk from nipple buckets to the calves did not cause significant differences in haematological blood indices, serum concentrations of glucose and IgG, and health status of calves compared to those suckling their mothers. Calves which remained with their mothers during colostrum feeding were characterized by a significantly lower concentration of serum cortisol at 2 days of age compared to calves that received colostrum from nipple buckets. Compared to the calves suckling their mothers (group I), the use of economical milk feeding system (III and IV groups) reduced rearing costs and increased the amount of milk intended for sale by 700-760 l/cow.

The aim of the study was to determine iron status in chosen organs of the European bison free ranging in Białowieża Primeval Forest. The material for analyses was obtained from animals eliminated during annual selection. Segments of liver, kidney, muscle, rib, and hoof were collected. Animals were divided depending on gender (males and females) and age (calves up to 1 year and animals older than 2 years). Mean iron concentration in liver was 263.59 mg ∙ kg^-1 fresh tissue. The iron content was significantly higher in the group of animals older than 2 years (P≤0.05). The average content of iron in kidneys amounted to 156.70 mg ∙ kg-1 fresh tissue. The average iron content in muscles amounted to 79.95 mg ∙ kg^-1 fresh tissue. Similarly to the liver samples a statistically significant difference (P≤0.05) was demonstrated depending on age. The average iron content in ribs and in the horn of the hoof wall of all European bison amounted to 38.90 mg ∙ kg^-1 fresh tissue and 47.87 mg ∙ kg^-1 dry matter, respectively. No statistically significant differences in the iron content were observed depending on gender.

This study presents an analysis of the yeast-like fungi population in the healthy horses’ living environment. The study material was sampled from various elements and equipment of a stable. We compared the yeast-like fungi population from the breeding environment of five groups of horses (English Thoroughbred horses, Arabian horses, Polish Half-Bred horses, cold-blooded horses, and Hucul horses and Highland ponies). The samples were collected in the summer and winter period. The laboratory examination involved 260 samples and resulted in identification of yeast-like fungi belonging to 13 species. Over 50% of the samples collected from the horse environment in wintertime and fewer than 18% of the summer samples displayed fungal growth. The largest amounts of yeast fungi were isolated from samples collected from water and feed troughs. The laboratory analysis demonstrated qualitative diversity of the yeast-like fungi population depending on the breeding environment of the individual horse groups. Quantitative differences of isolates were additionally related to the season of the year.

The aim of this study was to compare major biochemical properties of nutria meat with relevant composition and texture data of rabbit carcasses. The meat from nutria m. semimembranosus (MS; thigh muscle) contained 29.54% dry matter (DM), 20.05% total protein (TP), 7.83% total fat (TF) and 1.23% total ash (TA). The ratio of polyunsaturated fatty acids (PUFA) to saturated fatty acids (SFA) was lower in nutria than in rabbit meat (0.55-0.58 and 0.93-0.94, respectively). The n-6/n-3 PUFA ratio was 15.3 (MS) and 11.22 (m. longissimus dorsi, MLD; loin) in nutria meat and 7.55 and 8.08 respectively in rabbit meat, which appeared more beneficial for the consumer. Among the most important texture parameters, hardness ranged from 66 for MS to 73 N for MLD, and overall chewiness was 23 N. The collagen content was between 0.68 and 0.72%. The results show that in comparison with rabbit meat, nutria meat has valuable properties and is recommended for the human diet.

The purpose of this study was to analyse the colour of the breast muscles of Japanese Pharaoh quail on the first day after slaughter and again after further six days of cold storage, in relation to their muscle pH. The material for the study consisted of 40 breast muscles taken from the carcasses of six-week-old Japanese Pharaoh quail. Based on pH results, the muscles were divided into three groups: I (pH = 5.51-5.70), II (pH = 5.71-5.90) and III (pH = 5.91-6.10). After this the muscles were stored for a further 6 days at 4°C. It was found that the pH of freshly dissected quail breast muscle is a good indicator of the colour stability of muscles cold-stored at 4°C for six days. The lowest degree of colour stability was observed in the pH range 5.51-5.70. In the sensory evaluation muscles displaying this degree of colour instability were considered unacceptable or barely acceptable. In contrast, muscles in the pH ranges 5.71-5.90 and 5.91-6.10 displayed a high degree of colour stability and were considered acceptable in the sensory evaluation. The colour changes that occurred during storage of the muscles were due to changes in the values of all of the colour parameters (L*, a*, b*, C* and hº); however, the greatest changes were found in the case of redness (a*) and the hue angle (hº). The changes were caused both by alterations in the amount of pigment reached by light, and by changes in the relative amounts of the chemical forms of myoglobin.