Tom 21 (2021): Zeszyt 1 (January 2021)

Probiotics, prebiotics, synbiotics, direct-fed microbials, and herbs may improve the production efficiency in ruminants. The beneficial effect of selected specific microbes on animal health is reflected in protection against pathogens, stimulation of immunological response, increased production capacity, and mitigation of stress effects. Phytobiotic plants used in the nutrition of ruminant animals increase feed palatability. This in turn has a positive effect on feed intake and, consequently, increases production performance. Pectins, terpenes, phenols, saponins, and antibioticlike substances contained in phytobiotics prevent irritation, diarrhea, and increase the activity of digestive enzymes. Thanks to the abundance of biologically active substances such as flavonoids, glycosides, coumarins, carotenoids, polyphenols, etc., phytobiotics exhibit immunostimulatory and antioxidant properties as well. Given such a wide range of effects on health status and production parameters in animals, an attempt was made in this review to compile the current knowledge on the possible application of these natural growth stimulants in ruminant nutrition and to demonstrate their potential benefits and/or risks for breeding these animals.

Lipids (fats and oils) are a concentrated source of energy in poultry diets that improves palatability, feed consistency, provides essential fatty acids and increases the absorption of fat-soluble vitamins. Fresh oil is an expensive energy source and its exposure to air, heat, metallic catalyst during storage and processing may lead to its oxidative deterioration. This review highlights the response of modern poultry to dietary oxidized oil on growth performance, nutrients digestibility, gut health, carcass characteristics, meat quality, blood chemistry and tissue oxidative status. Literature shows that in moderately (peroxide value (PV): 20 to 50 meq kg⁻¹) and highly (PV: 50 to 100 meq kg⁻¹ or above) oxidized oils, lipid peroxidation causes rancid odours and flavours that negatively affect feed palatability, reduces intestinal villus height that decreases the surface area available for nutrients absorption. The oxidation products also damage fat soluble vitamins (A, D, E and K) in blood resulting in an oxidative stress. The use of oxidized oil in poultry diets has no significant effect on dressing percentage, pH and meat colour, whereas carcass weight decreases and drip loss of meat increases. Overall, there is a contradictory data regarding the influence of oxidized oil in poultry feed depending on the PV and inclusion levels. The reviewed literature shows that the use of mildly oxidized (PV < 20 meq kg⁻¹) oil in poultry feed with 4 to 5% inclusion level decreases the feed cost and ultimately cost of poultry production without compromising their growth performance. It can, therefore, partially replace fresh oil as an efficient, cost effective and sustainable energy source in poultry diets.

Aquaporins (AQPs) are a family of integral membrane proteins which form pores in cell membranes and take part in the transport of water, contributing to the maintenance of water and electrolyte balance and are widely distributed in various tissues and organs. The high expression of AQPs has been described in the digestive system, where large-scale absorption and secretion of fluids occurs. AQPs are also present in the nervous system, but the majority of studies have involved the central nervous system. This paper is a review of the literature concerning relatively little-known issues, i.e. the distribution and functions of AQPs in nervous structures supplying the digestive organs.

The discovery of antibiotics is considered one of the most crucial breakthroughs in medicine and veterinary science in the 20th century. From the very beginning, this type of drug was used as a ‘miraculous cure’ for every type of infection. In addition to their therapeutic uses, antibiotics were also used for disease prevention and growth promotion in livestock. Though this application was banned in the European Union in 2006, antibiotics are still used in this way in countries all over the world. The unlimited and unregulated use of antibiotics has increased the speed of antibiotic resistance’s spread in different types of organisms. This phenomenon requires searching for new strategies to deal with hard-to-treat infections. The antimicrobial activity of some plant derivatives and animal products has been known since ancient times. At the beginning of this century, even more substances, such as antimicrobial peptides, were considered very promising candidates for becoming new alternatives to commonly used antimicrobials. However, many preclinical and clinical trials ended without positive results. A variety of strategies to fight microbes exist, but we are a long way from approving them as therapies. This review begins with the discovery of antibiotics, covers the modes of action of select antimicrobials, and ends with a literature review of the newest potential alternative approaches to overcoming the drug resistance phenomenon.

Two mutations affecting the ovulation rate and litter size are segregating in Olkuska sheep population, FecX^O in the BMP15 gene, and the G7 site mutation in GDF9 gene. Homozygous carriers of both mutations are hyperprolific, contrary to the sterility observed in homozygous carriers of most other BMP15 and GDF9 mutations. The objective of this study was to assess frequency and phenotypic effects of both mutations. Blood samples were obtained from 740 individuals, 111 rams and 629 ewes, out of which 91 rams and 561 ewes were successfully genotyped for the BMP15 and GDF9 loci. The reproductive performance included a number of lambs born/born alive and a number of lambs reared until 60 days of age, and for a subset of ewe ovulation rates. The study proved a high frequency of the FecX^O mutation in two flocks that have been selected for many years for increased litter size (0.7–1.0 in breeding ewes and rams respectively), and a moderate frequency in another 19 private flocks (0.4–0.5). The frequency of the GDF9 mutation was low, with only 50 sheep out of 312 genotyped being carriers of the GDF9/G7 mutation, including three homozygous carriers. The FecX^O mutation in the BMP15 had a significant effect on both litter size and the ovulation rate. The single copy in heterozygous carriers increased litter size by 0.255 (0.063), while the effect of two copies in homozygous genotypes was +0.874 (0.081) lambs born. Due to the low frequency of the GDF9 mutation, it can only be preliminarily concluded that litter size has been increased in double carriers of both the BM15 and GDF9 mutation, which may suggest their additive interaction. The positive effect of both mutations supports their direct use in selection programmes.

The FASN enzyme plays a key role in fatty acids synthesis as the main long-chain fatty acid synthesizer. A non-synonymous SNP (single nucleotide polymorphism) (g.17925A>G) located in the thioesterase domain of this enzyme and an effect in fat deposition has been observed, but has not been evaluated in this breed and, moreover, the reason whereby this occurs remains unclear. The objective of this study was to evaluate the effect of this SNP on the activity of FASN enzyme in subcutaneous and intramuscular adipose tissue from Holstein Friesian steers. To achieve this, 196 animals were sampled in a local abattoir, genotyped for the FASN g.17924A>G SNP and characterized for fatty acid profile. Then a sub-sample of 20 animals per genotype were selected to extract the total protein from subcutaneous and intramuscular adipose tissue to estimate the FASN enzyme activity. The FASN activity for each genotyped animal was assessed indirectly by measuring the decrease in the absorbance of NADPH at 340 nm by spectrophotometry in a 24 well plate in the presence of Acetyl-CoA, Malonyl-CoA, and NADPH. To assess the impact of SNP induced amino acid changes in FASN protein structure, in-silico simulations were performed. Our results indicated that FASN g.17924A>G SNP induces a change in the enzyme activity in subcutaneous adipose tissue, which is higher when the AA genotype is present and lower in the presence of the AG genotype. The in-silico analysis of the amino acid substitution shows that there was a structural change in the dimeric form of the protein between genotypes. Moreover, the global energy between subunits is lower and more favorable when the AA genotype is present and higher and less favorable for the AG genotype. It was also found that the fatty acid profile of subcutaneous adipose tissue was affected when the AG genotype was present, decreasing the C16:0 fatty acid levels and increasing the C18:0 fatty acid levels. The FASN g.17924A>G SNP alters the FASN enzyme structure and activity, leading to a variation in the fatty acid composition of subcutaneous adipose tissue in Holstein Friesian steers. Implications: This SNP could be considered as a tool to improve the fat deposition or marbling and the fatty acid profile in cattle.

Native breeds of farm animals, despite their unique characteristics and adaptability to diverse and often adverse environmental conditions, are at risk due to their lower profitability and corresponding declining use. According to FAO data, there are currently around 8800 livestock breeds in the world (http://www.fao.org/dad-is/en/ update: 09.11.2019), of which 17% have been assessed to be endangered. The objective of the study was to develop a model for estimating the risk status of Polish native breeds. The proposed new model is based on 3 factors: demographic, genetic, and socioeconomic. The last factor is composed of 6 elements: geographical concentration, demographic trend over the last 5 years, cultural value of a breed, parentage control, ex situ conservation and anthropogenic factors. Using the factors and elements above, among the examined 30 breeds of cattle, horses, pigs, sheep and goats, 1 was assessed as being critically endangered; 24 were determined to be endangered and in need of conservation; 5 were less endangered, but in need of constant monitoring. Out of 35 populations of poultry 29 were assessed as endangered as they were being kept in only single public collections. Six flocks of ducks were given a critical risk status, due to a very low number of females.

In the present research we produced triploid, mitogynogenetic (doubled haploid; DH) and meiogynogenetic brook trout (Salvelinus fontinalis) to examine efficiency of these technologies and potential susceptibility of chromosome set manipulated individuals for the spinal disorders. Triploidy was induced by shocking (High Hydrostatic Pressure – HHP) of fertilized eggs 30 min. after insemination. In turn, gynogenetic development was induced by activation of eggs with UV-irradiated sperm. Activated eggs were then exposed to HHP shock applied 30 and 420 minutes after insemination to provide meiogynogenotes and gynogenetic DHs, respectively. When compared to non-manipulated diploids, the highest survival rates were observed among triploid brook trout while DHs showed the highest mortality. Malformation rates in the diploid larvae from the control groups did not exceed 7.0% while percentage of malformed triploid individuals equaled 19.1%. Drastically increased number of deformed larvae (> 30%) was observed in both DH and meiogynogenetic individuals. Intensification of kyphosis and scoliosis was clearly demonstrated in the gynogenetic and triploid brook trout. Genetic factors such as increased number of sets of chromosomes in triploids and expression of lethal alleles in the gynogenetic fish plus side effects of HHP shock utilized for retention of the second polar body or inhibition of the first cell cleavage when induced triploid and gynogenetic development have been discussed to affect survival rates and prevalence for the skeletal deformities in the chromosome set manipulated brook trout.

Searching for the associations between the gene polymorphism and the reproductive traits is essential in defining the genetic native breed specificity, which distinguishes them from the other breeds. The aim of our study was to determine the associations between mutations in the PRL, PRLR, PTGS2, FUT1 genes and sexual and periparturient activity in native Pulawska gilts. The analysis included 72 animals which gave birth to the first litter. Evaluation of the productive value of gilts accounted for indicators of sexual and periparturient activity as well as reproductive traits. The biological material for molecular analyses was obtained from the hair roots of the gilts. The genotype was verified by PCR RFLP analysis. The primers and PCR conditions were determined on the basis of available literature data. Statistically significant differences (P≤0.05) were found at the PRL locus: gilts of AA genotypes (Ins/Ins) at the PRL locus were characterised by longest farrowing duration compared to gilts of AB genotype (P≤0.05). The analysis of PRLR gene showed that gilts of TT genotype revealed a tendency for later occurrence of estrus signs (first and second estrus) and for the markedly longest farrowings (P≤0.05). With regard to PTGS2 and FUT1 loci, no significant differences were found in the parameters of sexual and periparturient activity of the gilts. However, gilts of FUT1 GG genotype gave birth to and reared the largest first litters (P≤0.05). The results of the studies expand the knowledge about the genetic structure and productivity of Pulawska gilts.

In this report, we describe the detection of bovine viral diarrhea virus (BVDV) contamination in commercial animal-derived sera and vaccines against animal viral pathogens on the market in Poland. Antibodies against BVDV were detected in 4/45 sera samples (8.9%) using an ELISA test. The presence of BVDV antigen was found using ELISA in 3/45 serum samples (6.6%) and 18/172 vaccine samples (10.5%). An RT -PCR was conducted using primers targeting two genome regions, the five prime untranslated region (5’UTR) and N-terminal protease (N^pro). BVDV RNA was detected in 33/45 (73.3%) of sera, and 11/172 samples (6.4%) of collected vaccines, of which one vaccine did not declare BVDV strain in its composition. A single serum showed the presence of an infectious virus and only one was contaminated with all 3 species of BVDV. The most frequent species in sera was BVDV-3 (75.5%), whereas in vaccines only BVDV-1 was identified. Sequence analysis showed that the tested commercial sera and one vaccine were contaminated by six genotypes of BVDV: -1a, -1b, -1c, -1d, -2a, and -3. Identification of BVDV and its genetic material in animal-derived products is important due to the possibility of pestivirus transmission as well as the chance of falsifying the results of a diagnostic test. It also demonstrates the necessity of rigorous monitoring of the bioproducts used at the laboratory and industry level.

Cystic endometrial hyperplasia-pyometra complex (CEH/P) significantly perturbs the reproductive performance of affected bitches and ovariohysterectomy (OHE) is a commonly applied treatment. Thus the only way to take advantage of the genetic potential of valuable females is application of assisted reproductive techniques (ART) mainly in vitro embryo production (IVP) or in some exceptional cases animal cloning by somatic cell nuclear transfer (SCNT). The aim of our study was to examine a potential effect of the CEH/P status on the quality of oocytes from females subjected to OHE. In total, 828 immature oocytes collected from ovaries of 33 bitches (21 control, 12 CEH/P) were subjected to genetic analyses (mRNA expression of two maternal-effect genes: GDF-9, OCT4 and mitochondrial DNA (mtDNA) content). Oocytes of CEH/P females were characterized by a higher mtDNA content (471 696) than gametes of their healthy counterparts (368 175; P<0.005). Transcripts for the two genes were detected in all samples and the mRNA level was not affected by the CEH/P status. In conclusion, the CEH/P complex does not exert a negative effect on oocyte quality reflected by the two parameters examined in this study.

The aim of this study was to examine the effect of thymosin beta 4 (Tβ4) during in vitro maturation (IVM) of oocytes and subsequent embryonic development after in vitro fertilization as well as to assess the quality of obtained blastocysts. Cumulus-oocyte complexes (COCs) were matured in vitro in 4 different media: 1. control medium; 2. control media supplemented with 50 ng/mL Tβ4; 3. control media supplemented with 0.5 mg/mL Tβ4; and 4. control media supplemented with 1 mg/mL Tβ4. The quality of the developed blastocysts was analysed by the TUNEL method. The number of cleaved eggs was significantly higher (P<0.05) when gametes were matured in the presence of 50 ng/mL Tβ4 than it was using the other types of media. Additionally, the largest number of blastocysts was observed when 0.5 mg Tβ4 was added to the medium (P<0.05). No significant difference was noted in the mean number of apoptotic nuclei per blastocyst or in the mean number of nuclei per blastocyst in any of the analysed groups. In conclusion, Tβ4 supplementation (50 ng/mL) in maturation medium increased the number of cleaved oocytes, and the number of blastocysts obtained increased when 0.5 mg/mL Tβ4 was used. This positive effect was not observed when a higher concentration of Tβ4 (1 mg/mL) was used.

This study evaluated the effects of grape seed extract (GSE) on the growth performance, immune response, and disease resistance of common carp (Cyprinus carpio). Fish were distributed in four groups and fed diets with varying levels of GSE at 0, 10, 20, and 30 g/kg for 56 days. The final length in fish fed with 20 and 30 g GSE/kg diet significantly increased in comparison with the control group (P<0.05). The final weight and weight gain of fish fed with GSE were statistically higher than for the control diet, while the feed conversion ratio was lower in GSE groups than the control. Hematological parameters did not statistically improve with GSE supplemented diets (P>0.05). However, fish fed with 30 g GSE/kg diet displayed a significantly higher WBC count than the other group (P<0.05). The serum total protein and globulin in fish fed with 20 g GSE/kg diet significantly increased compared to the control (P<0.05). A similar pattern was noticed in results for serum and mucus lysozyme activity with a significant increase in fish fed with 20 and 30 g GSE/kg diet compared to the control (P<0.05). Total antibody levels in serum and mucus samples were also increased in fish by dietary GSE with maximum levels by 20 and 30 g GSE/kg diet. Besides, mucus protease activity was higher in fish that received 20 and 30 g GSE/kg diet with maximum level shown in fish fed with 30 g GSE/kg diet compared to the control group (P<0.05). Meanwhile, all groups showed higher mucus antibacterial activity against Aeromonas hydrophila with the highest activity in 30 g GSE/kg diet in comparison with the control group. The cumulative mortality was 36.67% when fish were fed with 30 g GSE/kg diet and challenged with A. hydrophila. However, the mortality rate was 40% and 53.33% in fish fed 20 and 30 g GSE/kg diet, respectively. This study suggests that supplementation of GSE could significantly enhance the growth performance, immune responses, and disease resistance against A. hydrophila in common carp.

The present study aimed at evaluating the influences of pomegranate peel meal on the growth performance, hematology, and blood biochemistry of rainbow trout. Fish were fed 5 varying levels of pomegranate peel meal (0%, 1%, 2 %, 3%, and 4%) for 60 days. The obtained results showed that weight gain was significantly higher in fish fed at the rate of 1% than the other groups, while specific growth rate (SGR) was significantly increased in fish fed 1% and followed by the ration of 2% (P<0.05). SGR of fish fed at the rate of 4% revealed the lowest value among the groups (P<0.05). However, feed conversion ratio displayed the lowest values in fish fed at the rate of 1% or 2%, while the highest value was observed in fish fed at the rate of 4% (P<0.05). The survival rate was increased by the rate of 1% in relation to the control without differences with the other groups (P<0.05). Red blood cells were significantly higher in fish fed at the rate of 0%, 1%, and 2% than fish fed at the rate of 3% and 4%. Hematocrit and hemoglobin levels were increased by feeding pomegranate meal at the rate of 1% compared to the other groups, while fish fed the control diet displayed higher Hb and HCT levels than fish fed at the rate of 2%, 3%, and 4% (P<0.05). White blood cells displayed significant differences among the groups and increased by increasing the level of pomegranate meal in the diet. The blood total protein was decreased in fish fed 2%, 3%, and 4% compared to fish fed at the rate of 0% and 1% of pomegranate meal. The glucose value displayed the highest level in fish fed at the rate of 3% of pomegranate meal compared to the other groups. The triglycerides were reduced by pomegranate meal at the rate of 2% than 3% and 4% without differences with the control and 1%. The blood total cholesterol was reduced in fish fed at the rate of 1% of pomegranate meal compared to the other groups (P<0.05). The blood IgM and complement components (C3 and C4) were increased by increasing the supplementation level of pomegranate meal with the highest value in fish fed at the rate of 3% (P<0.05). In conclusion, dietary pomegranate meal at the rate of 1% is recommended for enhancing the growth rate and health status of rainbow trout.

The aim of the study was to determine the effect of these substitutions on body weight and slaughtering performance, post-mortem changes, sensory characteristics and chemical composition of selected muscle groups of male and female pheasants. The tests were carried out on pheasants during 5–16 weeks of rearing in enclosed aviaries. Four groups of 8 females and 8 males were formed, and the experimental factor was the supplementation of calcium, iron, zinc and copper salts with glycinates of these elements. The control group received a feed blend containing 100% of the mineral requirement as salts. In the E-25 group, 25% of the salts were replaced by glycinates, in the E-50 group 50% of the salts were replaced, and in the E-75 group only glycinates comprising 75% of the total mineral content were used and no salts were included, with vitamin D₃ replaced by calcitriol. For the duration of the study, feeding was at will and the birds had free access to water. In addition, pheasants were weighed at the age of 4, 8, 12 and 16 weeks. Daily feed intake was monitored. At the end of the experiment, when all the pheasants were 16 weeks old, they were weighed and decapitated. The breast, thighs and drumsticks and the heart, liver and gizzard were removed from the chilled carcasses. Supplementation of calcium, iron, zinc and copper salts with 50% glycinates in feed mixtures for pheasants over a period of 5–16 weeks resulted in a slight improvement in the slaughter weight of birds and a significant increase in crude ash, calcium and zinc, while at 75% supplementation and when calcitriol was used instead of vitamin D₃, increased phosphorus levels were found in the pheasant muscles analysed. Males had higher body weight, body weight gain, carcass, liver and gizzard weights, and their muscles had more magnesium and potassium and less calcium, sodium and iron than females.

The aim of the study was to determine the effects of inorganic (ferrous sulfate [FeSO₄] and FeSO₄ + phytase [FeSO₄+F]) and organic forms of iron (ferrous glycine chelate [FeGly], Fe-Gly + phytase [Fe-Gly+F]) on the concentrations of C-reactive protein (CRP), serum amyloid A (SA), alpha- 1-acid glycoprotein (α-AGP), haptoglobin (Hp), transferrin (TRF) and iron in the blood and liver tissue of poultry. Ross 308 roosters were used in this study. The acute-phase protein (AP) levels in the chicken serum and liver tissues were assayed using the double-antibody sandwich ELISA kits for chickens. The iron levels in serum and liver samples were measured using flame atomic absorption spectrophotometry. The results showed that the serum and hepatic iron concentration in the chickens receiving Fe-Gly and Fe-Gly-F were significantly higher than those in the control group and in the chickens receiving iron in the form of sulphates. Further, serum CRP and SA concentrations were lower in the chickens from the supplemented groups than in those from the control. The hepatic CRP concentration was higher in the supplemented groups than in the control group. The serum and hepatic TRF concentration were highest in the chickens receiving FeSO₄ and FeSO₄-F. The hepatic Hp concentration was higher in the chickens receiving organic forms of iron than in the control chickens, whereas the serum Hp concentrations were similar across the groups. The highest α-1-AGP concentration was found in the livers of the chickens receiving Fe- Gly and Fe-Gly-F. Taken together, these findings suggest that iron had the most beneficial effects for poultry in terms of health, performance and immunity when added to the feed in the form of glycine chelate.

In this study, the objective was to evaluate the effect of the age of Hy-line Brown hens – 44 and 60 weeks of age (26 and 42 weeks of laying) and housing system (enriched cages and litter) on the quality of eggs. According to our results, eggs with a better quality of albumen were obtained from younger hens than from older hens. Moreover, older hens produced eggs with inferior quality related to shell parameters, such as greater elastic deformation, poorer breaking strength, and thinner shells. However, hens kept in a litter housing system laid eggs with superior shell quality characteristics of less flexible and greater breaking strength, even though the thickness, weight, and percentage were similar in both housing systems. In addition, a higher amount and activity of lysozyme were obtained from eggs laid by hens kept in the litter housing system than those obtained from hens kept in cages. The maintenance system and age of birds also had a significant (P≤0.05) effect on the basic chemical composition of eggs, as well as on the proportion of individual elements and fatty acid profile. Taking these results into account, we can conclude that the more valuable characteristics from the morphological and nutritional point of view were observed in eggs obtained from younger Hy-line hens kept in the litter housing system.

In this study, we investigated the effect of modification of 12 d storage conditions of quail eggs from two flocks: at 17–20 weeks of life (A) and 36–39 weeks of life (B) on the incubation time, hatch window (HW), hatching results and chicks quality. The eggs were divided into experimental groups: COI = no pre-incubation (PI); SPIDES = were treated with 4 h PI, delivered at 4, 6, 8 and 10 d of storage; EG SPIDES = were treated with variable time of PI according to the scheme 5 d – 2 h, 7 d – 3 h, 9 d – 5 h and 11 d – 6 h. In addition, in each group, half of the eggs were turned (T) every 12 h, which is indicated as COI T, SPIDES T and EG SPIDES T. Pre-incubation was conducted at 37.8°C and 50–55% RH. It has been demonstrated that both storage profiles contribute to shortened incubation time, yet the HW is deteriorated if T is not applied. The benefits resulting from the EG SPIDES profile is an increase of 2.3 points in the “average score of all chicks” index compared to the COI group. In summary, the use of PI and T, and in particular the EG SPIDES profile with the concomitant use of T during long storage of quail eggs is recommended to obtain a considerable improvement of hatching results and chick quality.

In order to characterize the volatile compounds composition of lamb meat, 3 groups of baked leg muscle samples from two Polish native sheep breeds: Świniarka aged 9 months (S9), Wrzosówka aged 9 months (W9), and Wrzosówka aged 7 months (W7), were analyzed by HS-SPME-GC/MS, followed by multivariate statistics comprising the F-ratio method for variables pre-selection, and PCA-LDA analysis. Ninety seven volatile compounds were determined, out of which 74 were identified. The largest classes of volatile compounds were aldehydes and furans followed by alcohols, hydrocarbons, ketones, and sulfur and nitrogen compounds. Statistically significant differences between the S9, W9, and W7 groups were observed for 11 volatiles, i.e.: pentanal; hexanal; 1,3-octadiene; benzaldehyde; 3-ethyl-2-methyl-1,3-hexadiene; 3-octen-2-one; 2-octenal; 2-hexylfuran; tetradecanal; pentadecanal; hexadecanal. The HS-SPME-GC/MS method coupled with chemometrics, based on the relative intensity spectral data of these volatiles, proved to be an effective tool for the discrimination of lambs according to breed and age. The classification accuracy value for the S9, W9, and W7 groups was 100%.

The research was performed on 136 male lambs, at an average slaughter weight of 32 to 42 kg, of the following Polish native breeds: Uhruska (UHR), Pomeranian (Pomorska, POM), Blackheaded (Czarnogłówka, CZGŁ), Podhale Zackel (Cakiel Podhalański, CKP), Wrzosówka (WRZOS), Świniarka (SWIN), Wielkopolska (WLP) and Polish Merino old type (MST). The longissimus lumborum muscle was tested to establish its basic chemical composition, physical and chemical traits as well as sensory traits. The meat quality of tested breeds was high, especially in terms of sensory traits. However, high variability of studied traits was observed depending on the breed, e.g. the average pH₂₄ ranged between 5.58 (WLP) and 5.77 (WRZOS), intramuscular fat content ranged between 1.98% (CZGŁ) and 4.12% (WLP), meat tenderness varied from 4.2 points (POM) to 4.64 points (UHR). Somewhat dark meat colour was observed in all breeds which is worth noticing (L* from 34.86 to 38.50). According to the general estimation of tested quality traits the following breeds were on the top of the ranking: SWIN, UHR, WLP and WRZOS. Further down in the ranking the following breeds were placed: POM, MST and CKP.

The aim of this study was to investigate the variation of gross composition, somatic cell count, urea content, and fatty acids (FA) composition of bulk milk from single-breed and multi-breed farms in alpine area, keeping either Brown Swiss (BS), Holstein Friesian (HF), Simmental (SI), or their combinations. Gross milk composition, urea content, and FA composition were predicted using mid-infrared spectroscopy. Observations were grouped in 7 combinations consisting of 3 singlebreed and 4 multi-breed types of herd. A mixed linear model was used for data analysis, accounting for the fixed effects of herd composition (7 combinations), month of sampling, year of sampling, and the interactions between herd composition and month of sampling, and between herd composition and year of sampling. Farm was included as random effect. Results highlighted that about two thirds of South Tyrolean farms were single-breed and herds with more than 20 lactating cows changed herd structure over time, switching from multi- to single-breed. Single-breed BS farms produced milk with greater fat, protein, casein, lactose, and FA content than single-breed HF and SI farms. Further, multi-breed herds including BS cows produced milk with greater fat, protein, casein, and polyunsaturated FA content than multi-breed HF+SI herds. Overall, single-breed SI farms produced milk with lower somatic cell count than other herd combinations. Despite the number of BS cows in South Tyrol has decreased in favor of SI in the last years, this breed is still the most interesting for alpine dairy farming to achieve optimal milk quality in both single- and multi-breed scenarios. The tendency to move to SI is mainly related to good milk performance of SI cows coupled with their robustness, high carcass value, high market value of calves, and adaptability to mountain farming system.