Uticaj obima analiziranih podataka na vrednost koeficijenata heritabiliteta osobina veličine legla svinja

Low heritability of pig litter size traits at birth (number of live born piglets - LBP and total born piglets - TBP) and weaning (number of reared piglets - RP) is one of the major problems in their genetic improvement. The effect of selection is directly proportional to trait heritability and inversely proportional to the duration of generation interval. Objective of this study was to establish presence of difference in regard to heritability coefficient values of observed traits, as well as their accuracy depending on the size of data used in the analysis. Heritability coefficients in this study were calculated based on fertility results obtained for Swedish Landrace sows on three pig farms (farms 1, 2 and 3) in the Republic of Serbia. Observed traits - LBP, TBP and RP on farms 1, 2 and 3 were analyzed in the first (2422, 1677 and 2015 litters), in the first two (4190, 2897 and 3377 litters), in the first three (5576, 3809 and 4425 litters) and all available parities (9538, 6340 and 7750 litters) by applying the adequate mixed model of the Least square method. Heritability of LBP calculated based on fertility realized in the first partus ranged from 5.6 to 16.4 %, TBP ranged from 7.0 to 16.8 % and RP ranged from 3.4 to 7.7 %. Introduction into the analysis of the results pertaining to the second, third and subsequent parities lead mainly to detection of lower values of heritability coefficients for observed traits.U ovom radu rezultati istraživanja su pokazali da su koeficijenti heritabiliteta BŽP izračunati na osnovu plodnosti ostvarene u prvom prašenju bili u intervalu od 5,6 do 16,4 %, BUP u intervalu od 7,0 do 16,8 % i BOP u intervalu od 3,4 do 7,7 %. Uvođenje u analizu rezultata plodnosti drugog, trećeg i svih ostalih prašenja dovelo je uglavnom do utvrđivanja nižih vrednosti koeficijenata heritabiliteta posmatranih osobina

Naslednost i povezanost osobina veličine legla svinja utvrđena REML metodom

The aim of this study was to determine the heritability coefficients and the correlation between the number of live born piglets (NBA), the number of stillborn piglets (NSB), the number of total born piglets (NTB) and the number of weaned piglets (NW) in the part of population in Swedish Landrace sows in R. Serbia. The results obtained should enable the selection of litter size traits that would be proposed to be included in the selection - breeding program for this breed. The analysis of parameters was carried out on the basis of data on fertility of 4.061 Swedish Landrace sows and their 15.209 litters realized on two pig farms in R. Serbia. There was a genetic relationship between animals among the farms. Components of variance and covariance of observed traits, the share of additive genetic variance component in the phenotypic and correlation of traits at phenotypic and genetic levels, were evaluated using the method of Restricted Maximum Likelihood (REML) using the Multitrait Model (MM). Heritability estimates for the NBA, NSB, NTB and NW amounted to 6.4, 1.6, 6.7 and 1.1%, respectively. Correlation between the NBA and NTB at the phenotypic and genetic level was complete (rP = 0986, rG = 0938). Correlation between the NBA and NW at the phenotypic level has not been established, while at the genetic level it was weak. We believe that this is the result of the procedure of equalizing of litters after farrowing. In order to obtain objective genetic parameters for NW this procedure should not be applied in pure breed sows.Cilj istraživanja bio je da se utvrde koeficijenti naslednosti i povezanosti između broja živorođene prasadi (NBA), broja mrtvorođene prasadi (NSB), broja ukupno rođene prasadi (NTB) i broja odgajene prasadi (NW) u delu populacije krmača rase švedski landras u R. Srbiji. Dobijeni rezultati treba da omoguće izbor osobina veličine legla koje bi bile predložene za uključivanje u selekcijsko - odgajivački program za ovu rasu. Ocena analiziranih parametara sprovedena je na osnovu podataka o plodnosti 4061 krmača rase švedski landras i njihovih 15209 legala ostvarenih na dve farme svinja u R. Srbiji između kojih postoji genetska povezanost među životinjama. Komponente varijanse i kovarijanse posmatranih osobina, udeo aditivne genetske komponente varijanse u fenotipskoj i povezanost osobina na fenotipskom i genetskom nivou ocenjene su metodom ograničene najveće verovatnoće (REML - Restricted Maximum Likelihood) primenom višeosobinskog modela (MM - Multitrait Model). Heritabiliteti za NBA, NSB, NTB i NW su iznosili 6.4, 1.6, 6.7 i 1.1 %, respectively. Povezanost NBA i NTB na fenotipskom i na genetskom nivou je bila potpuna (rP = 0.986, rG = 0.938). Povezanost NBA i NW na fenotipskom nivou nije utvrđena, dok je na genetskom bila slaba. Smatramo da je to posledica postupka ujednačavanja legala posle prašenja. Radi dobijanja objektivnih genetskih parametara za NW ovaj postupak ne treba primenjivati kod čistorasnih krmača

The Assessment of Breeding Value of First Farrowed Sows by the Method of Selection Indices

The goal of this research paper was to assess the breeding value of first farrowed Swedish Landrace sows by the means of selection indices method. The traits on the basis of which the breeding value of animals was assessed are following: daily liveweight gain, average thickness of collected back fat measured at five sites and number of liveborn piglets in the first litter. The liveweight gain and carcass quality traits determined at the end of performance test were corrected for the body mass of 100kg by the method of basic indexes and following mean values were determined: for corrected daily liveweight gain (KZDP) 499.92g/day and for corrected average collected backfat thickness (KSL) 20.01mm. The first farrowed sows on average produced 8.09 liveborn piglets in the litter. Studying the effect of the gilts` birth year and season on KZDP and KSL it was determined that the gilts` birth year and season had no statistically significant influence (P>0.05) on KZDP variation but they had a statistically significant effect on KSL (P lt 0.01). The year and the season of farrowing and the class of backfat thickness in performance test did not display any statistically significant effect (P>0.05) on BZPL, while the KZDP class and the age at first farrowing had a statistically significant effect on the variability of these trait (P lt 0.05; P lt 0.01). All studied traits varied statistically significantly (P lt 0.01) under the impact of the gilts` sire or dam. Heritability coefficients were: h2= 0.402 for KZDP, h2= 0.261 for KSL and h2= 0.177 for BZPL. The relation between KZDP and KSL was of a medium strength both at phenotype and genetic levels (rph=0.491; rg=0.411), while the relation of these traits with BZPL did not exist, except for the genetic relationship between KSL and KZDP which was of a medium strength (rg=0.252). Three equations for the selection indexes were constructed among which as the most optimal was chosen the one which includes all three traits (KZDP, KSL and BZPL) and whose correlation coefficent of selection index and aggregate genotype was rIAG = 0.5473

Osobine ejakulata i reproduktivna efikasnost nerasta velikog jorkšira tokom iskorišćavanja

The main objective of this study was to assess the variability of ejaculate properties: volume of ejaculate (VOL, ml), sperm concentration (CON, spermatozoa/ml), total sperm count (NT) and the number of doses produced (NPD) per ejaculate under the influence of season, boar and the interval between two mounts. Reproductive efficiency of boars was analysed based on the farrowing rate (FR). The study included 341 ejaculates from seven Large White boars. Impact assessment was carried out by applying the GLM procedure of the statistical package SAS 9.1.3. The average values of VOL, CON, NT, NPD and FR were: 244.28 ml, 203.77x106 spermatozoa/ml, 43.48x109 spermatozoa, 17.39 doses and 67.58%. Ejaculate properties varied under the influence of season (P lt 0.01, P lt 0.001). The interval between two mounts did not affect only the variability of CON. The difference between the best and worst boars was 91.99x106 spermatozoa/ml of ejaculate (P lt 0.001). During summer VOL ejaculate was the lowest (191.36 ml). The highest NPD (19.04 doses) was produced during the autumn months, and during the same period the highest concentration of sperm was recorded (242.16x106 spermatozoa/ml). Regardless of the differences in the farrowing rate between boars not being statistically significant (P=0.0882), it is necessary to perform the ranking and promptly identify boars with farrowing rate below average.Osnovni cilj istraživanja bio je da se oceni varijabilnost osobina ejakulata: volumen ejakulata(VOL, ml), koncentracija sperme (CON, spermatozoida/ml), ukupan broj spermatozoida (NT) i broj proizvedenih doza (NPD) po ejakulatu pod uticajem nerasta, sezone i intervala izmedju dva skoka. Reproduktivna efikasnost nerasta analizirana je na osnovu procenta prašenja (FR). Istraživanjem je bio obuhvaćen 341 ejakulat sedam nerasta velikog jorkšira. Ocena uticaja je izvršena primenom GLM procedure u statističkom paketu SAS 9.1.3. Prosečne vrednosti VOL, CON, NT, NPD i FR bile su: 244,28 ml, 203,77x106 spermatozoida/ml, 43,48x109 spermatozoida, 17,39 doza i 67,58%. Osobine ejakulata varirale su pod uticajem sezone (P lt 0,01; P lt 0,001). Interval između dva skoka nije uticao jedino na varijabilnost CON. Razlika izmedju najboljeg i najlošijeg nerasta bila je 91,99x106 spermatozoida/ml ejakulata (P lt 0,001). Tokom letnjih meseci VOL ejakulata bio je najmanji (191,36 ml). Najveći NPD (19,04 doza) proizveden je tokom jesenjih meseci, a tokom istog perioda bila je i najveća koncentracija sperme (242,16x106 spermatozoida/ml). Bez obzira što razlike u procentu prašenja između nerasta nisu bile statistički značajne (P=0,0882), potrebno je vršiti rangiranje i pravovremeno identifikovati neraste sa procentom prašenja ispod proseka

Mogućnosti upotrebe selekcijskog indeksa u proceni priplodne vrednosti krava Holštajn rase u Srbiji

The conducted research was aimed at constructing equations of selection index that would be used in the selection of the Holstein-Friesian breed animals in Serbia. The construction of the selection index includes the most important milk traits observed in standard lactation: milk yield (MY305), milk fat content (% MF305) and protein content (% MP305). The variance and covariance necessary for the construction of selection index are calculated using the mixed model by the method of least squares. The economic value of traits is expressed as a ratio of relative changes in costs per unit of traits included in the selection index. Livestock included in the research produced, in the first standard lactation, an average of 7681 kg of milk with 3.58% milk fat and 3.28% protein. The equation of the selection index presented in the paper is selected from the group of equations of selection index, as an equation with the highest correlation between the equation and the aggregate genotype, which amounted to 0.2156.Sprovedeno istraživanje imalo je za cilj konstruisanje jednačine selekcijskog indeksa koja bi se koristila u odabiru grla holštajn-frizijske rase u Srbiji. U konstrukciju selekcijskog indeksa uključene su najvažnije osobine mlečnosti posmatrane u standardnoj laktaciji: prinos mleka (PM305), sadržaj mlečne masti (%MM305) i sadržaj proteina (%MP305). Varijanse i kovarijanse neophodne za konstrukciju selekcijskog indeksa izračunate su primenom mešovitog modela metodom najmanjih kvadrata. Ekonomska vrednost osobina je izražena kao odnos relativne promene troškova po jedinici osobina uključenih u selekcijski indeks. Grla obuhvaćena istraživanjem prosečno su proizvela u prvoj standardnoj laktaciji 7681 kg mleka sa 3,58 % mlečne masti i 3,28% proteina. Jednačina selekcijskog indeksa prikazana u radu odabrana je iz grupe jednačina selekcijskog indeksa, kao jednačina sa najvećom korelacijom između jednačine i agregatnog genotipa, koja je iznosila 0,2156.

Naslednost i povezanost osobina plodnosti krmača

Purpose of this paper was to determine fertility traits heritability coefficients of the sows (number of live born, total number of born, stillborn and reared piglets in the litter) and interconnections between these traits. Heritability coefficients were low and averaged in interval from h2 = 0,056 for number of reared piglets in litter to h2 = 0,142 for total number of born piglets in litter, which is in accordance with heritability values for reproductive traits. Genetic interconnections of these traits had wide variation interval and averaged from r = - 0,221 between number of still born and reared piglets in litter to r = 0,947 between total number of born and number of live born piglets in litter. Coefficients of phenotype correlation varied in interval from r = -0,162 between number of still born and number of live born piglets in litter to r = 0,909 between total number of born and number of live born piglets in litter.Cilj rada bio je da se utvrde koeficijenti naslednosti osobina plodnosti krmača (broj živorođene, ukupno rođene, mrtvorođene i odgajene prasadi u leglu) i međusobna povezanost ovih osobina. Koeficijenti heritabiliteta su bili niski i kretali su se u intervalu od h2 = 0,056 za broj odgajene prasadi u leglu do h2 = 0,142 za broj ukupno rođene prasadi u leglu, što je u skladu sa vrednostima heritabiliteta za reproduktivne osobine. Genetska povezanost ovih osobina imala je širok interval variranja i kretala se od r = -0,221 između broja mrtvorođene i broja odgajene prasadi u leglu, do r = 0,947 između broja ukupno rođene i broja živorođene prasadi u leglu. Koeficijenti fenotipske korelacije kretali su se u intervalu od r = -0,162 između broja mrtvorođene i broja živorođene prasadi u leglu, do r = 0,909 između broja ukupno rođene i broja živorođene prasadi u leglu

Osobine kvaliteta polutki i mesa svinja rase moravka i mangulica

Objective of this paper was to evaluate phenotypic variability of carcass side traits and quality of meat of fatteners (male castrated heads) of Moravka breed (M) and Mangalitsa (swallow-belly Mangalitsa - LM). The quantity and content of meat were determined based on dissection of left carcass sides (Walstra and Merkus, 1996). Also, nutritive properties of musculus longissimus dorsi (m.l.d.) were established. Obtained data were processed using GLM procedure of the program package SAS 9.1.3 (SAS Inst.Inc., 2002-2003). Results of the study show that Moravka fatteners had longer carcass sides (+6.82 and + 5.00 cm) compared to Mangalitsa breed, corrected to average body weight at slaughtering. Fatteners of M breed had in average higher total mass of back-loin part (+0.685, P lt 0.05) and average quantity of muscles in the same part of carcass side (+0.631 kg, P lt 0.01), compared to fatteners of LM breed. Also, they had higher quantity of muscle in belly-rib part (+0.237 kg, P lt 0.05) compared to LM. Share of muscle tissue in back-loin and belly-rib carcass side parts corrected for WCC, was higher in M carcass sides than in LM (P lt 0.01). Conversely, muscle tissue content in shoulders of Mangalitsa was higher (+4.8% ; P lt 0.05) than in Moravka. Share of muscle tissue in carcass sides of M pigs was by 4.3% higher compared to LM carcass sides. In m.l.d. of Moravka water content was higher (+6.1%, P lt 0.01), content of total lipids (-6.5%, P lt 0.05) and cholesterol (-19.68 mg/100 g, P lt 0.001) was lower than in Mangalitsa.Rezultati ispitivanja pokazuju da su tovljenici rase moravka imali duže polutke od rase mangulica, korigovane na prosečnu telesnu masu pri klanju. Tovljenici rase M imali su prosečno veću ukupnu masu leđno-slabinskog dela (P lt 0,05) i prosečnu količinu mišića u istom delu polutki (P lt 0,01), nego rase LM. Takodje, oni su imali i veću količinu mišića u trbušno-rebarnom delu (P lt 0,05) nego LM. Udeo mišićnog tkiva u leđno-slabinskom i trbušno-rebarnom delu korigovan na WCC, bio je veći polutkama M nego kod LM (P lt 0,01). Obrnuto, sadržaj mišićnog tkiva u plećkama mangulice bio je veći nego kod moravke (P lt 0,05). Udeo mišićnog tkiva u polutkama svinja M, bio je za 4,3% veći nego u polutkama LM. U m.l.d. moravke bio je veći sadržaj vode (P lt 0,01), manji sadržaj ukupnih masti (-6,5%, P lt 0,05) i holesterola (-19,68 mg/100g, P lt 0,001) nego kod mangulice

Phenotypic and genetic variability of sows productive and longevity traits

Istraživanje je sprovedeno na jednoj farmi svinja u Republici Srbiji i obuhvatilo je proizvodne rezultate 4768 plotkinja (nazimica ili krmača) rase švedski landras i njihovih meleza F1 generacije sa rasom veliki jorkšir. Ispitivanjem je bilo obuhvaćeno četri grupe osobina i to: osobine porasta i kvaliteta trupa nazimica i osobine veličine legla i dugovečnosti krmača. Ukupno je analizirano devet osobina: životni dnevni prirast nazimica (ŽDP), uzrast na kraju testa nazimica (UKT), prosečna debljina slanine nazimica (DS), dubina MLD – a nazimica (DM), procenat mesa u trupu nazimica (PM), broj živorođene prasadi u leglu krmača (BŽP), dužina produktivnog života krmača (DPŽ), ukupan broj prašenja krmača (UBP) i ukupan broj živorođene prasadi krmača (UBŽP). Utvrđene su sledeće prosešne vrednosti ispitivanih osobina: ŽDP 525,51 g/dan; UKT 189,53 dan; DS 14,50 mm; DM 47,43 mm; PM 56,44 %; BŽP 10,31; DPŽ 739,92 dan; UBP 5,14 i UBŽP 52,85. U analizi sistematskog dela modela svih ispitivanih osobina korišćene je metod najmanjih kvadrata, dok je kod osobina dugovečnosti pored navedenog metodološkog postupka korišćen i metod analize preživljvanja (Vejbulov model - Weibull model) kako bi se utvrdila statistička značajnost i nivo rizika za ispoljenost ovih osobina po ispitivanim faktorima varijabilnosti. ŽDP, UKT, DS, DM i PM su statistički značajno varilali pod uticajem sezone kraja performans tetsta, kao i pod uticajem genotipa nazimice, sa izuzetkom DM gde nije ustanovljena statistička značajnost delovanja ovog faktora. Regresijski uticaj završne telesne mase u testu bio je značajan kod svih osobina kod kojih je bio uključen u model (ŽDP, DS, DM, PM). BŽP je statistički značajno varirao pod uticajem svih ispitivanih fiksnih i regresijskih faktora (redosled prašenja, sezona uspešne oplodnje, genotip krmače, otac legla, klasa trajanja prethodnog perioda zalučenje - oplodnja, starost krmače unutar prašenja, trajanje prethodne laktacije). DPŽ, UBP i UBŽP su statistički značajno varirali pod uticajem genotipa krmače, sezone prve uspešne oplodnje, broja živorođene prasadi u prvom legu, uzrasta pri masi od 100 kg, prosečne debljine slanine pri masi od 100 kg i starosti krmače pri prvom prašenju...The trial was conducted on one of the pig farms in the Republic of Serbia and included production results of 4768 breeding females (gilts and sows) of the Swedish Landrace breed and their F1 generation crossbreds with Great Yorkshire breed. The trial included four groups of traits such as follows: the traits of weight gain and quality of gilt carcass and the traits of the size of litter and longevity of sows. In total following nine traits were analysed: gilts lifetime daily weight gain (ŽDP), gilts age at the end of test (UKT), average thickness of bacon in gilts (DS), depth of MLD in gilts (DM), percentage of meat in gilt carcass (PM), number of live-born piglets in sow litter (BŽP), length of sow productive life (DPŽ), total number of sows farrowing (UBP) and total number of live-born piglets per sow (UBŽP). Following average values of studied traits were determined: ŽDP 525,51 g/day; UKT 189,53 day; DS 14,50 mm; DM 47,43 mm; PM 56,44 %; BŽP 10,31; DPŽ 739,92 day; UBP 5,14 and UBŽP 52,85. In the analysis of systematic part of model which involved all studied traits we have used the Least Square Method while longevity traits, besides aforementioned methodological procedure, were analysed also by means of the survival analysis method (Weibull model) in order to determine statistical significance and level of risk for these traits manifestation per studied variability factors. ŽDP, UKT, DS, DM and PM statistically significantly varied under the influence of season of the end of performance test, as well as under the influence of gilt genotype with the exception of DM where statistical significance of the effect of this factor was not determined. Regression influence of finishing body mass in test was significant in all traits in which it was included in the model (ŽDP, DS, DM, PM). BŽP statistically significantly varied under the impact of all studied fixed and regression factors (order of farrowing, season of successful conception, sow genotype, sire of the litter, class of duration of previous period weaning - conception, age of sow at farrowing, length of previous lactation). DPŽ, UBP and UBŽP statistically significantly varied under the influence of sow genotype, season of the first successful conception, number of live-born piglets in the first litter, age at the mass of 100 kg, average thickness of bacon at the mass of 100 kg and age of sow at the first farrowing..

Phenotypic and genetic variability of sows productive and longevity traits

Istraživanje je sprovedeno na jednoj farmi svinja u Republici Srbiji i obuhvatilo je proizvodne rezultate 4768 plotkinja (nazimica ili krmača) rase švedski landras i njihovih meleza F1 generacije sa rasom veliki jorkšir. Ispitivanjem je bilo obuhvaćeno četri grupe osobina i to: osobine porasta i kvaliteta trupa nazimica i osobine veličine legla i dugovečnosti krmača. Ukupno je analizirano devet osobina: životni dnevni prirast nazimica (ŽDP), uzrast na kraju testa nazimica (UKT), prosečna debljina slanine nazimica (DS), dubina MLD – a nazimica (DM), procenat mesa u trupu nazimica (PM), broj živorođene prasadi u leglu krmača (BŽP), dužina produktivnog života krmača (DPŽ), ukupan broj prašenja krmača (UBP) i ukupan broj živorođene prasadi krmača (UBŽP). Utvrđene su sledeće prosešne vrednosti ispitivanih osobina: ŽDP 525,51 g/dan; UKT 189,53 dan; DS 14,50 mm; DM 47,43 mm; PM 56,44 %; BŽP 10,31; DPŽ 739,92 dan; UBP 5,14 i UBŽP 52,85. U analizi sistematskog dela modela svih ispitivanih osobina korišćene je metod najmanjih kvadrata, dok je kod osobina dugovečnosti pored navedenog metodološkog postupka korišćen i metod analize preživljvanja (Vejbulov model - Weibull model) kako bi se utvrdila statistička značajnost i nivo rizika za ispoljenost ovih osobina po ispitivanim faktorima varijabilnosti. ŽDP, UKT, DS, DM i PM su statistički značajno varilali pod uticajem sezone kraja performans tetsta, kao i pod uticajem genotipa nazimice, sa izuzetkom DM gde nije ustanovljena statistička značajnost delovanja ovog faktora. Regresijski uticaj završne telesne mase u testu bio je značajan kod svih osobina kod kojih je bio uključen u model (ŽDP, DS, DM, PM). BŽP je statistički značajno varirao pod uticajem svih ispitivanih fiksnih i regresijskih faktora (redosled prašenja, sezona uspešne oplodnje, genotip krmače, otac legla, klasa trajanja prethodnog perioda zalučenje - oplodnja, starost krmače unutar prašenja, trajanje prethodne laktacije). DPŽ, UBP i UBŽP su statistički značajno varirali pod uticajem genotipa krmače, sezone prve uspešne oplodnje, broja živorođene prasadi u prvom legu, uzrasta pri masi od 100 kg, prosečne debljine slanine pri masi od 100 kg i starosti krmače pri prvom prašenju...The trial was conducted on one of the pig farms in the Republic of Serbia and included production results of 4768 breeding females (gilts and sows) of the Swedish Landrace breed and their F1 generation crossbreds with Great Yorkshire breed. The trial included four groups of traits such as follows: the traits of weight gain and quality of gilt carcass and the traits of the size of litter and longevity of sows. In total following nine traits were analysed: gilts lifetime daily weight gain (ŽDP), gilts age at the end of test (UKT), average thickness of bacon in gilts (DS), depth of MLD in gilts (DM), percentage of meat in gilt carcass (PM), number of live-born piglets in sow litter (BŽP), length of sow productive life (DPŽ), total number of sows farrowing (UBP) and total number of live-born piglets per sow (UBŽP). Following average values of studied traits were determined: ŽDP 525,51 g/day; UKT 189,53 day; DS 14,50 mm; DM 47,43 mm; PM 56,44 %; BŽP 10,31; DPŽ 739,92 day; UBP 5,14 and UBŽP 52,85. In the analysis of systematic part of model which involved all studied traits we have used the Least Square Method while longevity traits, besides aforementioned methodological procedure, were analysed also by means of the survival analysis method (Weibull model) in order to determine statistical significance and level of risk for these traits manifestation per studied variability factors. ŽDP, UKT, DS, DM and PM statistically significantly varied under the influence of season of the end of performance test, as well as under the influence of gilt genotype with the exception of DM where statistical significance of the effect of this factor was not determined. Regression influence of finishing body mass in test was significant in all traits in which it was included in the model (ŽDP, DS, DM, PM). BŽP statistically significantly varied under the impact of all studied fixed and regression factors (order of farrowing, season of successful conception, sow genotype, sire of the litter, class of duration of previous period weaning - conception, age of sow at farrowing, length of previous lactation). DPŽ, UBP and UBŽP statistically significantly varied under the influence of sow genotype, season of the first successful conception, number of live-born piglets in the first litter, age at the mass of 100 kg, average thickness of bacon at the mass of 100 kg and age of sow at the first farrowing..

Phenotypic and genetic variability of sows productive and longevity traits

Istraživanje je sprovedeno na jednoj farmi svinja u Republici Srbiji i obuhvatilo je proizvodne rezultate 4768 plotkinja (nazimica ili krmača) rase švedski landras i njihovih meleza F1 generacije sa rasom veliki jorkšir. Ispitivanjem je bilo obuhvaćeno četri grupe osobina i to: osobine porasta i kvaliteta trupa nazimica i osobine veličine legla i dugovečnosti krmača. Ukupno je analizirano devet osobina: životni dnevni prirast nazimica (ŽDP), uzrast na kraju testa nazimica (UKT), prosečna debljina slanine nazimica (DS), dubina MLD – a nazimica (DM), procenat mesa u trupu nazimica (PM), broj živorođene prasadi u leglu krmača (BŽP), dužina produktivnog života krmača (DPŽ), ukupan broj prašenja krmača (UBP) i ukupan broj živorođene prasadi krmača (UBŽP). Utvrđene su sledeće prosešne vrednosti ispitivanih osobina: ŽDP 525,51 g/dan; UKT 189,53 dan; DS 14,50 mm; DM 47,43 mm; PM 56,44 %; BŽP 10,31; DPŽ 739,92 dan; UBP 5,14 i UBŽP 52,85. U analizi sistematskog dela modela svih ispitivanih osobina korišćene je metod najmanjih kvadrata, dok je kod osobina dugovečnosti pored navedenog metodološkog postupka korišćen i metod analize preživljvanja (Vejbulov model - Weibull model) kako bi se utvrdila statistička značajnost i nivo rizika za ispoljenost ovih osobina po ispitivanim faktorima varijabilnosti. ŽDP, UKT, DS, DM i PM su statistički značajno varilali pod uticajem sezone kraja performans tetsta, kao i pod uticajem genotipa nazimice, sa izuzetkom DM gde nije ustanovljena statistička značajnost delovanja ovog faktora. Regresijski uticaj završne telesne mase u testu bio je značajan kod svih osobina kod kojih je bio uključen u model (ŽDP, DS, DM, PM). BŽP je statistički značajno varirao pod uticajem svih ispitivanih fiksnih i regresijskih faktora (redosled prašenja, sezona uspešne oplodnje, genotip krmače, otac legla, klasa trajanja prethodnog perioda zalučenje - oplodnja, starost krmače unutar prašenja, trajanje prethodne laktacije). DPŽ, UBP i UBŽP su statistički značajno varirali pod uticajem genotipa krmače, sezone prve uspešne oplodnje, broja živorođene prasadi u prvom legu, uzrasta pri masi od 100 kg, prosečne debljine slanine pri masi od 100 kg i starosti krmače pri prvom prašenju...The trial was conducted on one of the pig farms in the Republic of Serbia and included production results of 4768 breeding females (gilts and sows) of the Swedish Landrace breed and their F1 generation crossbreds with Great Yorkshire breed. The trial included four groups of traits such as follows: the traits of weight gain and quality of gilt carcass and the traits of the size of litter and longevity of sows. In total following nine traits were analysed: gilts lifetime daily weight gain (ŽDP), gilts age at the end of test (UKT), average thickness of bacon in gilts (DS), depth of MLD in gilts (DM), percentage of meat in gilt carcass (PM), number of live-born piglets in sow litter (BŽP), length of sow productive life (DPŽ), total number of sows farrowing (UBP) and total number of live-born piglets per sow (UBŽP). Following average values of studied traits were determined: ŽDP 525,51 g/day; UKT 189,53 day; DS 14,50 mm; DM 47,43 mm; PM 56,44 %; BŽP 10,31; DPŽ 739,92 day; UBP 5,14 and UBŽP 52,85. In the analysis of systematic part of model which involved all studied traits we have used the Least Square Method while longevity traits, besides aforementioned methodological procedure, were analysed also by means of the survival analysis method (Weibull model) in order to determine statistical significance and level of risk for these traits manifestation per studied variability factors. ŽDP, UKT, DS, DM and PM statistically significantly varied under the influence of season of the end of performance test, as well as under the influence of gilt genotype with the exception of DM where statistical significance of the effect of this factor was not determined. Regression influence of finishing body mass in test was significant in all traits in which it was included in the model (ŽDP, DS, DM, PM). BŽP statistically significantly varied under the impact of all studied fixed and regression factors (order of farrowing, season of successful conception, sow genotype, sire of the litter, class of duration of previous period weaning - conception, age of sow at farrowing, length of previous lactation). DPŽ, UBP and UBŽP statistically significantly varied under the influence of sow genotype, season of the first successful conception, number of live-born piglets in the first litter, age at the mass of 100 kg, average thickness of bacon at the mass of 100 kg and age of sow at the first farrowing..