Martyna Batorska

Effect of restricted feeding and realimentation periods on pork quality and fatty acid profile of M. longissimus thoracis.

An experiment with 94 fattening pigs (48 gilts and 46 barrows) was conducted to determine the effect of feeding 25% restricted diets at different body weights on meat quality and fatty acid profile of M. longissimus thoracis (LT). During the 84 days of the experiment (4 periods, 21 days each), animals with an initial weight of about 31 kg were fed in different periods of observation ad libitum (A) or restricted diets (R) in groups AAAA, AARA, RAAA and RARA. After 21 days of the experiment, the restricted-fed pigs, compared to those fed ad libitum, had a lower total fat content of M. longissimus thoracis (P<0.05), higher shear force (P=0.068), and lower proportions of SFA (C14:0, C18:0 P<0.05) and MUFA and higher proportions of PUFA (C20:4, C22:4 P<0.05) in the fatty acid profile. Three weeks after the restricted feed supply was lifted, the total fat content in LT muscle was higher than in animals fed ad libitum throughout (2.34 vs. 2.02), very close after the next 3 weeks of realimentation (3.16 vs. 3.15) and lower after another 3 weeks (3.19 vs. 3.49). Regardless of the time at which restricted feeding was started and the number of restricted feeding periods, the total fat content in the LT muscle at the end of the experiment was similar or lower in groups RAAA, AARA and RARA, compared to group AAAA. The coefficient of correlation between the total fat content in LT and the shear force was -0.36 (P<0.01). Colour, pH and drip loss did not depend on the level of nutrition. After 84 days of observation, animals from groups RARA and AARA, compared to pigs from groups AAAA and RAAA, were characterized by a slightly higher shear force of LT, lower SFA and MUFA (P<0.001), and higher n-6 PUFA (P<0.01) and n-3 PUFA (P<0.01) proportions in the fatty acid profile. The fatty acid profiles of AAAA pigs and pigs undergoing a 63-day realimentation period (RAAA) were similar. Regardless of the feeding scheme, the n-6:n-3 ratio exceeded 10 in all the groups.

Effect of sow prolificacy and nutrition on preand postnatal growth of progeny – a review

Abstract Weakened growth and development of embryos as well as of fetuses or their organs (IUGR) show a relationship with increasing sow fertility. When aiming to increase birth weight in piglets and reduce within-litter variation in piglet body weight, efforts should be made to maintain a favourable maternal environment (uterus-placenta-embryo). Intrauterine undernutrition can be limited through the hormonal and/or nutritional treatment of pregnant sows. This has an effect on prenatal myogenesis, resulting in better development of skeletal muscles, higher birth weight of piglets, and progression in postnatal growth rate.

Effect of selenium supplementation in pig feed on slaughter value and physicochemical and sensory characteristics of meat.

Abstract The aim of the study was to examine the assimilability of organic and inorganic selenium supplied as an additive to pig feed. The influence of both selenium forms on pig slaughter value as well as on the physicochemical and sensory characteristics of meat was also examined (experiment I). An attempt to establish the distribution of selenium in the body of experimental fatteners was made (experiment II). Experiment I was performed on 20 carcasses of crossbred pigs of (Polish Large White × Polish Landrace) × Duroc genotype and experiment II was carried out on 45 samples of longissimus and semimembranosus muscles taken from fatteners of the same genotype (PLW × PL × Duroc). The results obtained indicated that selenium supplementation in the diet had no impact on slaughter performance, meat quality and most physicochemical and sensory characteristics of meat. Selenium was found to have no significant effect on meat colour. The meat water holding capacity (WHC) was lower in the group of pigs fed organic selenium. The highest selenium concentration was found in the semimembranosus muscle of fatteners receiving the inorganic selenium additive.

Effect of Piglet Birth Weight on Carcass Muscle and Fat Content and Pork Quality – A Review

Abstract Piglet birth weight is determined by the maternal environment, intrauterine crowding, and nutrition, which influence embryonic and fetal survival and, as a result, fertility. The internal environment regulates prenatal myogenesis and muscle fibre number nutritionally and hormonally. The growth and metabolic differentiation of muscle fibres take place during the postnatal period. The effect of intrauterine undernutrition on myogenesis and on fetal growth and development (IUGR) is reflected in the low piglet birth weight and its high within-litter variation. Slaughter traits are determined by many factors, including genetic (breed), environmental (nutrition) and preslaughter handling. Slaughter traits and the physico-chemical and sensory characteristics of meat are dependent on prenatal myogenesis and neonatal weight. Optimized body weight of newborn piglets is conducive to improving quantitative traits (meatiness, fatness) and qualitative traits. However, slaughter traits are also influenced by many other differentiating factors, which is reflected in research results. Muscle fibres become metabolically differentiated during postnatal development, and one of the factors of large variation in pig meat quality traits is variation in the proportions of different fibre types in mature muscle. Considering the divergent opinions among scientists about the effect of prenatal myogenesis and piglet birth weight on slaughter value and pork quality, as well as the existence of areas that have received little investigation, it is justified to continue research in this area.

Effect of Piglet Birth Weight on Selected Characteristics of Pork

Abstract The objective of the study was to determine how different birth weights of piglets influence some chemical and physical characteristics of pig meat. Piglets were grouped according to birth weight: ≤1.30 kg (group I), 1.31-1.70 kg (group II), ≥1.71 kg (group III). Animals were reared and fattened under standardized housing and feeding conditions. Tests were conducted with 60 samples of meat (20 per group) collected from the right side of the carcasses (M. longissimus lumborum) of threebreed crosses of (Polish Landrace × Polish Large White) × Duroc (barrows to gilts, 1:1), which were slaughtered at about 180 days of age. Determinations were made of basic chemical composition, colour of meat, drip loss, shear force value, and fatty acid profile. It was found that the birth weight of the piglets affects meat colour (redness), crude fat content and the proportion of some fatty acids (C16:1, C20:1 n-9, C20:2 n-6, C20:5 n-3).

Comparison of changes in fatness of sows in high pregnancy and at weaning and determination of their association with reproduction results and rearing of piglets

Sixty crossbred sows were investigated for the effect of the level of fat reserves in high pregnancy and pre-weaning changes in lipid reserves on reproductive performance of sows and rearing of piglets. At 104 days of pregnancy and at weaning, sows were analysed for body weight, P2 and P4 backfat thickness and M. Longissimus dorsi (MLD) thickness at P4M (Piglog 105). Sows were grouped according to mean backfat thickness (P2 + P4)/2 at 104 days of pregnancy into primiparous (P2 + P4)/2>18 mm (group I), primiparous (P2 + P4)/2≤18 mm (group II), multiparous (P2 + P4)/2>20 mm (group I) and multiparous (P2 + P4)/2≤20 mm (group II). The body weight of sows from group I was higher than sows from group II at 104 days of pregnancy (P ≤ 0.05) and at weaning (P ≤ 0.01). As assumed in the experiment, fatness in high pregnant sows (points P2 and P4) was significantly higher in group I than in group II (P ≤ 0.01), and the differences between the groups persisted when piglets were weaned (P ≤ 0.01). At weaning, sows from group II had a significantly greater P4M thickness compared to sows from group I. The differences in backfat thickness in late-pregnant sows in groups I and II and in the loss of fat reserves during a 21-day lactation had no effect on reproduction results and rearing of piglets. Sows lost body weight to a small extent and fat reserves to a moderate degree; the changes were greater in primiparous than multiparous sows, regardless of the group (I or II).

The effect of carcass weight on chemical characteristics and fatty acid composition of Longissimus dorsi and Semimembranosus muscles of European wild boar (Sus scrofa scrofa) meat

Abstract: The objective of this study was to investigate the effect of carcass weight on chemical characteristics and fatty acid composition of m. longissimus dorsi and m. semimembranosus of European wild boar (Sus scrofa scrofa) meat. The research was carried out on 50 wild boars shot during four battues at hunting reserves in the central part of Poland. The carcasses were divided into three groups: ≤30 kg (G1), 31–45 kg (G2), and >45 kg (G3). The protein concentration increased with carcass weight (P ≤ 0.01). The concentration of saturated fatty acids was influenced by carcass weight and was higher when weight increased. A significantly higher level of monounsaturated fatty acids (MUFA) was found in the carcasses of wild boars from G3 compared with G1 group (P ≤ 0.01). The content of C18:2n-6 was significantly lower in the lightest carcasses compared with the heaviest (P ≤ 0.05). Statistical analysis confirmed that carcasses weight significantly affected polyunsaturated fatty acids (PUFA) n-3 content. The lightest carcasses contained a significantly higher concentration of PUFA n-3 (P ≤ 0.01). In addition, in G3, the amount of C22:5n-3 was two-fold lower (P ≤ 0.01) than in G1. The research has shown that the meat quality was affected by the carcass weight, resulting better parameters in the lighter than in the heavier carcasses. Therefore, most of the culled wild boars should be squeakers and young boars after the first year of life.

THE EFFECT OF HOUSING SYSTEM ON THE INCIDENCE OF INTESTINAL PARASITE INFESTATION IN PIGS

The aim of the study was to compare the intestinal parasite fauna occurring in pigs kept in different rearing conditions (group A – extremely extensive, B – extensive and C – intensive). In the period between March and July 2010, 345 samples of faeces from piglets (125), weaners (60), fatteners (94) and sows (66) were collected and tested, using standard coproscopic methods. Six parasitic species, belonging to phylum Nematoda (Strongyloides ransomi, Ascaris suum, Oesophagostomum dentatum, Trichuris suum) and to phylum Apicomplexa (Isospora suis and Eimeria debliecki) were diagnosed. Eggs of Toxascaris leonina, a parasitic roundworm mostly affecting the members of the Canidae and Felidae families, not encountered in pigs until now, were found in the faeces of fatteners. The highest level of parasite invasion was recorded in pigs from group A and B; they were multi-species invasions. Parasitic species found in faeces not only bring economic losses, but they may also be dangerous for human health and life, which indicates the necessity to implement parasitological screening protocols, especially in the extensive rearing conditions.