Ewa Skrzypczak

Variability in the melanocortin 1 receptor (MC1R) gene in wild boars and local pig breeds in Poland

Source/description: Studies on the variability in the MC1R gene sequence in pigs made it possible to identify many polymorphic sites, which may be responsible for variations in the coat pigmentation in individual breeds. Moreover, utilising the SNP identification scheme in the MC1R gene described by Kijas et al., Koutsogiannouli et al. carried out investigations on the utilisation of a genetic test (PCR-RFLP) for the identification of interspecific crosses. It was concluded, on the basis of their experiments, that restrictive analysis employing the BspHI enzymes may be useful for genetic differentiation of Large White pigs from wild boars as well as interspecific cross-breeds (Large White x wild boar).

The Influence of Fattening and Slaughter Traits on Reproduction in Polish Large White Sows

The aim of the study was to determine the influence of growth rate, back fat thickness, loin eye height and meatiness on the reproductive performance of sows based on the first two reproduction cycles. This study was conducted on 348 sows of the Polish Large White breed maintained in farm conditions. It was observed that the sows from the group with the lowest weight gains (≤600 g) were characterised by the latest age of first farrowing, which was 374 days, and the lowest number of live born piglets in a litter (12.13 heads). Statistical analysis also demonstrated that females from the group with the thickest back fat (>15 mm) bore the lowest number of live piglets in a litter (on average 11.47 heads), and the difference between this group and the others was highly significant. Considering the influence of standardised loin eye height on reproduction traits, the smallest litters (11.53 heads) were observed in the group of females with the lowest loin eye height (≤55 mm). Sows with the lowest standardised meatiness (≤55%) had the least numerous litters: 11.87 live-born piglets. In turn, the highest number of live-born piglets was reported in the group of sows with the highest meatiness (>60%). Based on these results, it may be concluded that improvement in fattening and slaughter traits did not have a negative influence on the reproduction efficiency in the first two production cycles.

Impact of sow milk protein polymorphism on piglet rearing.

Impact of Sow Milk Protein Polymorphism on Piglet Rearing The aim of the investigations was to ascertain interrelationships between polymorphic fractions of milk proteins and rearing results of piglets from Złotnicka White sows. The experimental material comprised 20 sows of the native Złotnicka White breed. Pigs of this breed are included in the National Genetic Resources Conservation Programme. Investigations included two successive (2nd and 3rd) lactations of sows during which the following parameters were determined: number and weight of piglets on days 1, 7, 14, 21 and 28; weight gains of individual piglets during the period from day 1 to 7, from day 8 to 14, from day 15 to 21 and from day 22 to 28; as well as mortality for the entire period of rearing, i.e. from day 1 to day 28 of age. A total of 425 piglets born in 40 litters (20 sows x 2 lactations) were investigated. As a result of electrophoretic separations, the following four protein fractions were isolated from sow milk: αs1-casein (CSN1S1), genotypes AA, AB, BB and BC; β-casein (CSN2), genotypes AA, AB and BB; κ-casein (CSN3), genotypes AA, AB and BB; β-lactoglobulin (LGB), genotypes AA and BB. The present study showed that milk from sows of AA CSN1S1 and AA LGB genotypes appeared to be more valuable and nourishing, as indicated by the fact that these sows reared piglets which were characterized by the best production results, i.e. body weight, weight gains and the lowest percentage mortality. The least dynamic results were obtained by piglets originating from litters of sows of the AA-CSN3 genotype. Wpływ polimorfizmu białek mleka loch na odchów prosiąt Celem podjętych badań było dostarczenie informacji na temat związku między polimorficznymi frakcjami białek mleka a rezultatami w odchowie prosiąt loch rasy złotnickiej białej. Materiał zwierzęcy stanowiło 20 loch rodzimej rasy złotnickiej białej. Świnie ras złotnickich objęte są Krajowym Programem Ochrony Zasobów Genetycznych. Badanie obejmowało dwie kolejne laktacje loch (2. i 3.). W czasie trwania doświadczenia określono następujące parametry: liczbę i masę prosiąt w 1., 7., 14., 21. i 28. dniu życia, przyrosty poszczególnych prosiąt w okresie od 1. do 7. dnia, od 8. do 14. dnia, od 15. do 21. dnia i od 22. do 28. dnia oraz straty za cały okres odchowu, tj. od 1. do 28. dnia życia. Łącznie poddano doświadczeniu 425 prosiąt, pochodzących z 40 miotów (20 loch x 2 laktacje). W wyniku rozdziału elektroforetycznego w mleku loch wyizolowano 4 następujące frakcje białkowe: αs1-kazeinę (CSN1S1) genotypy: AA, AB, BB, BC; β-kazeinę (CSN2) genotypy: AA, AB, BB; κ-kazeinę (CSN3) genotypy: AA, AB, BB oraz β-laktoglobulinę (LGB) genotypy: AA, BB. Prace badawcze dowiodły, że mleko loch o genotypie AA CSN1S1 i AA LGB wydaje się być najbardziej wartościowe i odżywcze. Efektem tego był fakt, że lochy te odchowały prosięta, które charakteryzowały się najlepszymi wynikami produkcyjnymi, tzn. masą, przyrostami i najmniejszym procentem upadków. Najmniej dynamiczne wyniki osiągnęły prosięta pochodzące z miotów loch o genotypie AA-CSN3.

Effect of Thermal Stress on Reproductive Performance Parameters of Sows with Defined Genotype at the RYR1 locus

Effect of Thermal Stress on Reproductive Performance Parameters of Sows with Defined Genotype at the RYR1 locus The objective of the present research was to determine the influence of ambient air temperature in the farrowing section of a pig facility on chemical composition, colostrum and milk somatic cell counts (SCC), and rearing efficiency of piglets from Polish Landrace (PL) sows with identified genotype at the RYR1 locus. Subjects were 60 PL sows in the second and third reproductive cycle. Polymorphism at the RYR1 locus was analysed using the PCR-RFLP method. The proportion of RYR1 C/C and RYR1 C/T genotypes in each group was 1:1. Three groups of experimental temperatures were established: I - 22°C, II - 25°C, III - 28°C. The present study demonstrated that sows kept in periodic high ambient temperature (25°C, 28°C) showed a relatively long period of farrowing, more aggressive behaviour and overlying. Variability was also found between the groups with respect to litter size and litter weight, chemical composition and SCC of colostrum and milk. The results indicate that elevated ambient temperature during the perinatal period may adversely affect the utility value of sows. Wpływ stresu termicznego na wskaźniki reprodukcyjne loch o ustalonym genotypie w locus RYR1 Celem przeprowadzonych badań i analiz było określenie oddziaływania temperatury powietrza w sektorze porodowym chlewni na skład chemiczny, liczbę komórek somatycznych siary i mleka oraz wyniki odchowu prosiąt loch rasy polskiej białej zwisłouchej o zidentyfikowanym genotypie w locus RYR1. Materiał zwierzęcy stanowiło 60 loch rasy polskiej białej zwisłouchej (pbz) w drugim i trzecim cyklu reprodukcyjnym. Analizę polimorfizmu w locus RYR1 wykonano metodą PCR-RFLP. Liczebność genotypów RYR1 C/C i RYR1 C/T w każdej grupie wynosiła 1:1. W zakresie temperatur doświadczalnych przyjęto trzy grupy: I - 22°C, II - 25°C, III - 28°C. W przeprowadzonych badaniach wykazano, iż lochy utrzymywane w okresowo wyższej temperaturze otoczenia (25°C, 28°C) wykazywały relatywnie dłuższy czas porodu, większą liczbę zachowań agresywnych i przygnieceń prosiąt. Stwierdzono również zmienność cech pomiędzy grupami w odniesieniu do liczebności i masy miotu, składu chemicznego i LKS siary oraz mleka. Uzyskane wyniki wskazują, iż podwyższona temperatura otoczenia w okresie okołoporodowym może mieć niekorzystny wpływ na wartość użytkową loch.

Analysis of reproduction and litter performance of the Zlotnicka Spotted breed and its different crossbreeds

Zlotnicka Spotted (ZS) is a native Polish pig breed. It is characterized by low reproduction and litter performance. This study aimed to determine the suitability of ZS pigs when crossed with Duroc and Polish Large White (PLW) according to reproduction and litter performance. Data concerning the number of piglets in the litter, litter weight, litter balance and piglet wastage were evaluated at birth, on the 7th and 21st days, and during weaning. ZS sows in purebred litters had 8.82 piglets at birth. However, the number of weaned piglets was of particular importance being only 7.33 heads in this study population. Wastage in purebred litters up to weaning was 17.34%. The highest number of piglets at birth (10.76 heads) and number of weaned piglets (8.98 heads) were estimated for D/ZS x ZS litters, although, at weaning, the heaviest piglets (9.61 kg) came from PLW x ZS litters. Results show that crossing ZS sows with Duroc, PLW boars, as well as crossing of D x ZS, improves reproduction and litter performance.

The influence of the different content of protein fractions in sows’ milk in piglet rearing

The aim of this study was to investigate the influence of the percentage content of protein fractions in total protein of sow`s colostrums and milk and their influence on the traits related with piglet rearing. The animal specimens were 20 sows of the native Zlotnicka White breed. Zlotnicka pigs were subjected to the National Genetic Resources Conservation Programme. Colostrum and milk were collected between the 20th and 24th h after parturition and on the 2nd, 3rd, 7th, 14th and 21st day of lactation. A total of 120 samples (60 colostrum samples and 60 milk samples) were collected from all active mammary glands. Individual fractions of total protein were separated by means of electrophoresis on polyacrylamide gel in the presence of sodium dodecyl sulphate (SDS). The piglets’ body weights average daily gains and mortality were checked consecutively after 24 hours after parturition and on the day 7 th , 14 th , and 21 st of lactation. 207 piglets were examined. A highly significant correlation between the number of piglets, daily growths and protein fractions was observed. The most favourable rearing results were obtained at the highest level (III) of individual fractions. The study also proved most of the piglets are lost from the litters when the level of fractions is the lowest (I). Keywords: Sows, milk, protein fractions, Zlotnicka White, piglet rearing

The effect of sex, slaughter weight and weight gains in PEN-AR-LAN fatteners on their slaughter value

The aim of the study was to determine the effect of sex, body weight and growth rates on basic fattening and slaughter indexes in PEN-AR-LAN fatteners. The research was conducted on 274 PEN-ARLAN hybrid fatteners coming from sows of the Naima maternal line and was sired by boars of the P-76 meat line. Recorded fattening and slaughter performance values indicated that PEN-AR-LAN hybrid pigs could be good material for the production of fatteners. The highly significant effect of sex on back fat thickness and meat content and significant effect on the loin eye area were shown. Gilts were characterized by higher meatiness (56.2 vs. 53.4%) and lower back fat thickness (16.4 vs. 20.3 mm) than castrated males. Fatteners with lower slaughter weight were characterized by thinner backfat and smaller height of the loin ‘eye’. No significant effect of the slaughter weight on the meat content in the carcass was found. Fatteners with daily weight gains below 700 g had the thinner backfat amounting to 16.7 mm (at P ≤ 0.01) in comparison with 19.6 and 19.5 mm for animals with higher weight gains. Animals with lower weight gains had the higher meatiness (55.7%, at P ≤ 0.01) in comparison with animals of higher weight gains (54.2 and 53.7%). Key words : Pigs, PEN-AR-LAN, slaughter value, sex, slaughter weight, daily gain.

A genome-wide detection of selection signatures in conserved and commercial pig breeds maintained in Poland

BackgroundIdentification of selection signatures can provide a direct insight into the mechanism of artificial selection and allow further disclosure of the candidate genes related to the animals’ phenotypic variation. Domestication and subsequent long-time selection have resulted in extensive phenotypic changes in domestic pigs, involving a number of traits, like behavior, body composition, disease resistance, reproduction and coat color. In this study, based on genotypes obtained from PorcineSNP60 Illumina assay we attempt to detect both diversifying and within-breed selection signatures in 530 pigs belonging to four breeds: Polish Landrace, Puławska, Złotnicka White and Złotnicka Spotted, of which the last three are a subject of conservative breeding and substantially represent the native populations.ResultsA two largely complementary statistical methods were used for signatures detection, including: pairwise FST and relative extended haplotype homozygosity (REHH) test. Breed-specific diversifying selection signals included several genes involved in processes connected with fertility, growth and metabolism which are potentially responsible for different phenotypes of the studied breeds. The diversifying selection signals also comprised PPARD gene that was previously found to have a large effect on the shape of the external ear in pigs or two genes encoding neuropeptide Y receptors (Y2 and Y5) involved in fat deposition and stress response which are important features differentiating the studied breeds. REHH statistics allowed detecting several within-breed selection signatures overlapping with genes connected with a range of functions including, among others: metabolic pathways, immune system response or implantation and development of the embryo.ConclusionsThe study provides many potential candidate genes with implication for traits selected in the individual breeds and gives strong basis for further studies aiming at identification of sources of variation among the studied pig breeds.

Effect of slaughter weight and sex on slaughter traits and meat quality of Polish autochthonous ZLotnicka Spotted pigs crossbred with Duroc

Abstract The aim of this study was to investigate the impact of slaughter weight and sex on slaughter traits and meat quality of Zlotnicka Spotted x Duroc (ZS×D) hybrid fatteners. The material comprised 56 Zlotnicka Spotted × Duroc fatteners (28 barrows and 28 gilts) which were fattened to 245th day of life. Pigs were divided into the following three groups: Group I (n=16) <110 kg; Group II (n=23) ≥110 ≤120 kg, and Group III (n=17) >120 kg. The obtained results revealed influence of the final body weight on slaughter trait values with the exception of meatiness. Fatteners from the group with the highest weight were characterised by the thickest backfat as well as by the greatest height of the loin eye. Slaughter weight exerted a significant impact on protein content, water absorbability as well as on the pH of the longissimus thoracis et lumborum (LTL) muscle. As to the influence of sex on slaughter traits, it was found that gilts were characterised by smaller backfat thickness and higher carcass meatiness than barrows. On the other hand, no effect of the slaughter weight and sex on colour parameters and sensory quality of the LTL muscle was ascertained. All the examined parameters were at high level in all slaughter weight and sex groups. The obtained results suggest that the slaughter of ZS×D crossbreds in groups I and II exerts a beneficial influence on slaughter trait levels and, at the same time, allows maintenance of high meat quality.

The physicochemical properties of offal from Pulawska gilts in relation to carcass meatiness

Abstract The aim of this study was to determine the relationship between the meatiness of the Puławska pig carcass and selected physical and chemical parameters of pork offal. The study was conducted on a group of 50 porkers of the native Puławska breed, whose carcasses were classified into five classes: E, U, R, O, and P, covering 10 specimens each. Samples were collected from the tongue, heart, lungs, liver and kidneys, and the pH (pH45, pH24), percentage of free water and chemical composition (ash, fat, protein) were determined. To summarise the obtained results, it can be concluded that the increase of the meat content in carcass significantly and primarily affects the reduction of the offal’s weight and then the reduction of the pH45 as well as the increase of the free water content primarily in the kidney and the lungs. In the case of chemical composition an increase of the meatiness in the carcass affected the reduction of fat content in the kidneys, lungs, heart and liver. The liver and the heart were the offal with the greatest susceptibility to the effects of the carcass meatiness. In this offal the increase of the carcass meatiness significantly decreased the fat content and energy value, and also increased the ash and protein content. Offal from the studied meatiness classes of the pigs’ carcasses was characterised by adequate quality and suitability for processing.