Reproductive Traits Of Sows Research Articles

Use of feed additive Actigen in the production of compound feed for pregnant sows

The introduction of various innovative technologies in diff erent branches of animal husbandry involves the use of various non-traditional feed additives in animal diets, which contribute not only to the disclosure of genetic potential, but also to the removal of heavy metals from the body of animals, bees and poultry. The purpose of the research was to use the Actigen feed additive in the production of compound feed for pregnant sows. Scientifi c and economic experiment in improving the production technology of compound feed for pregnant sows was carried outunder the conditions of a compound feed plant at Agrofi rm Ariant LLC. The object of the study was compound feed, as well as pregnant sows. For the research, 2 groups of pregnant sows (control and experimental) were formed per 10 heads in each according to the principle of pairs-analogues. The sows of control group compound feed without the Actigen feed additive was given, and the sows of experimental group it was with Actigen additive. The Actigen feed additive was used at a dose of 0.5 kg per 1 ton of compound feed. The results of the experiment showed that the experimental group produced by 9 live piglets more than the control group, and the average weight of one piglet in the experimental group was0.15 kg more than in the control group. There were 4 stillborn piglets in the control group, which was 1 head or 33.3 % more than in the experimental group. The average live weight of one piglet at weaning in the experimental group was 6.00 kg, which was 0.80 kg more than in the control group. The weight of the litter at weaning in the control group was 54.08 kg, and in the experimental groupit was 69.60 kg, which was 15.52 kg more than in the control group. Thus, the Actigen feed additive at the dose of 0.5 kg per 1 ton of compound feed had a positive infl uence on the reproductive traits of sows.

Identification of Genomic Regions and Candidate Genes for Litter Traits in French Large White Pigs Using Genome-Wide Association Studies.

Simple SummarySow reproductive performance is crucial in the entire pig industry. However, the heritability of reproductive traits is slowthat it is difficult to make great genetic progress by traditional breeding methods. Therefore, in this study, we performed genome-wide association analyses of litter traits in French White sows to explore genes related to sow reproductive traits and we finally detected a notable region (10.72–11.06 Mb on chromosome 7) and four promising genes (JARID2, PDIA6, FLRT2 and DICER1). The results of this study provide a theoretical basis for subsequent molecular breeding.The reproductive traits of sows are one of the important economic traits in pig production, and their performance directly affects the economic benefits of the entire pig industry. In this study, a total of 895 French Large White pigs were genotyped by GeneSeek Porcine 50K SNP Beadchip and four phenotypic traits of 1407 pigs were recorded, including total number born (TNB), number born alive (NBA), number healthy piglets (NHP) and litter weight born alive (LWB). To identify genomic regions and genes for these traits, we used two approaches: a single-locus genome-wide association study (GWAS) and a single-step GWAS (ssGWAS). Overall, a total of five SNPs and 36 genomic regions were identified by single-locus GWAS and ssGWAS, respectively. Notably, fourof all five significant SNPs were located in 10.72–11.06 Mb on chromosome 7, were also identified by ssGWAS. These regions explained the highest or second highest genetic variance in the TNB, NBA and NHP traits and harbor the protein coding gene ENSSSCG00000042180. In addition, several candidate genes associated with litter traits were identified, including JARID2, PDIA6, FLRT2 and DICER1. Overall, these novel results reflect the polygenic genetic architecture of the litter traits and provide a theoretical reference for the following implementation of molecular breeding.

Reproductive characteristics of pigs of Irish selection and manifestation of different forms of heterosis by different methods of breeding in modern conditions of industrial pork production

The manifestation of different forms of heterosis and its effect on the reproductive capacity of pigs of modern genotypes of Irish selection by different methods of breeding in domestic industrial production on breeding and commercial breeders LLC “SPE “Globinsky pig farm.” To compare the reproductive capacity of animals in purebred breeding, crossbreeding, and hybridization and their dependence on the manifestation of various forms of heterosis of potential and actual multiplicity, high fertility, and nest weight of piglets at birth and weaning, the number of weaned piglets per nest and their safety. A comprehensive assessment of the reproductive qualities of sows was determined using an evaluation index with a limited number of traits, and the selection index of reproductive qualities of sows was determined according to the proposed method. Heterosis indices were determined by V. T. Gorin and I. M. Nikitchenko and modified by O. M. Tserenyuk. Biometric processing of the obtained data was performed by using variation statistics using a personal computer software Microsoft Excel. It was found that the indicators of reproductive traits of sows of all experimental groups and combinations studied were characterized by high reproductive performance, except for purebred sows of the synthetic line Max Gro. Sows of large white and landrace breeds in their direct and reverse cross outperformed their purebred counterparts in birth by 2.8 % in terms of fertility, 2.2 % in terms of nest weight of piglets at birth, and 1.7 % in terms of high fertility. They weighed 4.1 % more piglets, weighed 1.3 % more weight, and 4.6 % the weight of the nest, while the preservation of piglets before weaning was not significantly different between animals of these groups. According to a comprehensive assessment of reproductive indicators, they were 2.8–3.3 % higher when crossing parent breeds than their purebred breeding. At the final stage of hybridization, the advantages of hybrid nests over purebreds (maternal form) during farrowing were established – by potential and actual fertility by 3.9 % and 2.2 %, respectively, by nest weight of piglets at birth and high fertility by 6.3%, and 6.8 %. When weaned, their preferences were – for the safety of piglets – 1.7–2.0 %, for the number of piglets, the weight of their nest, and the weight of one head when weaned by 5.7–6.5 % and 8.5 % and 4.2 %, respectively. According to a comprehensive assessment of sows using the SIVYAS index and the index of reproductive qualities of sows with a limited number of traits, an advantage of 3.9 % and 3.3 % of hybrid nests over purebreds was established. At the same time, sows in hybridization outperformed purebred analogs of the synthetic line Max Gro at the time of farrowing by potential and actual multiplicity by 34.2 % and 59.1 %, nest weight by nest weight of piglets at birth by 27.8 % but had a lower by 25.8, 8.0 % high fertility. At the time of weaning in hybrid nests, there were 54.1 % more piglets, 11.8 % higher live weight of 1 head, and 8.5 % live weight of nests of piglets, according to a comprehensive assessment of sows for SIVYAS and IVYa by 25.9 and 31.8 %, respectively, but they have a 4.6 % worse safety of piglets compared to analogs of the synthetic line Max Gro. There was a more pronounced effect of heterosis on such features as the number of piglets at weaning, live weight of the nest at weaning, SIVYAS and evaluation index, and moderate level of heterosis effect on the average weight of 1 head at weaning at 28 days and average daily gain of young for suckling period. Under the conditions of two-breed crossbreeding, an increase in reproductive indicators was found to a greater extent due to the manifestation of hypothetical and general forms of heterosis, while in hybridization, in most cases, specific and authentic heterosis was manifested.

Reproductive traits of sows with different duration of feeding of biologically active additives in their diet

The addition to the main diet of sows of additional trace elements (copper, zinc, cobalt, manganese) 10–50 mg/kg of live weight, vitamin B₉ (folic acid) 35 mg/head. and Hexavit 196 mg/ head/day is the most effective in comparison with its use during the last third of pregnancy. The highest effect was obtained of all the compared groups when using a combination of trace elements with Hexavit and all the studied additives together. At the same time, the cobalt content in the blood of sows of these groups has been decreased by 3,3 and 5,0 times, and manganese by 2 times. In the first half of pregnancy, the addition of folic acid against the background of trace elements in the diet of sows had a more positive effect on individual indicators of metabolic metabolism in comparison with other groups. However, in the last third of pregnancy, the best results were observed in the group with Hexavit: the total protein content increased by 3,8 %, urea decreased by 57,6 (P ≤ 0,001), glucose increased by 25,1 %. The feed additive of trace elements and folic acid in the diet of sows in comparison with the control group increased the total number of piglets in the litter by 10,2 %, trace elements and Hexavit by 22,0, with their total use by 18,6 % (P ≥ 0,05), and the number of live piglets by 7,1 %, 9,1 and 15,2 %, respectively. At the same time, the consumption of compound feed, energy and protein per piglet decreased by 6,6 %, 16,1 and 13,2 %, respectively. The use of vitamin and mineral additives with Hexavit in the diet of sows in the last third of pregnancy, as well as with the addition of folic acid, increased the number of newborn piglets by 6,3 %, and live piglets by 2,6 and 1,8 %, respectively. Folic acid alone with trace elements did not have the positive effect on the reproductive traits of sows.

Influence of feed additives on the reproductive traits of sows

Currently, the main condition for the intensification of animal husbandry in Russia is the application of the concept of rational animal feeding. In accordance with this concept, animals should be provided with complete feed, and the organization of feeding should provide conditions for the effective use of feed and the regulation of microbiological digestive processes. The purpose of the work was to study the effectiveness of the effect of the phytobiotic “Intebio” and the probiotic “Profort” on the reproductive traits of sows. The scientific and economic experiment was conducted in 2020 on pregnant and suckling sows under the conditions of OOO “Agrofi rma Ariant” (Krasnogorsky settlement in the Emanzhelinsky area in the Chelyabinsk region). The results of research of the effect of phytobiotic “Intebio” and probiotic “Profort” on the reproductive traits of sows have been presented in the article. It has been found according to the results of the conducted research that feeding sows phytobiotic “Intebio” and probiotic “Profort” in addition to the main diet for 30 days before farrowing and for 30 days after the survey allows to increase the prolificacy of sows by 2,9 and 1,9 %, respectively, the weight of piglets at birth by 12,3 and 10,4 %, the weight at weaning by 11,9 and 11,2 %, the livability of piglets by 6,1 and 4,0 %. This made it possible to reduce expenditures feed per 1 kg of piglets’ live weight gain by 18,4 and 15,6 %. It has been found on the base of conducted research that the use of phytobiotic “Intebio” and probiotic “Profort” in the feeding of pregnant and suckling sows is economically justified.

Correlations between microsatellite DNA heterozygosity and reproductive traits in Large White sows

The main aim of this paper was to determine whether heterozygosity (assessed using microsatellite genotypes) was correlated with the reproductive traits in sows. The study was conducted on two herds of sows of the Large White sows breed at the Limited Liability Company “Tavriys’ki svyni” (Kherson region, Ukraine) and the Agricultural Private Enterprise “Techmet-Yug” (Mykolayiv region, Ukraine). During the study, we used eleven microsatellite loci recommended by International Society for Animal Genetics (ISAG) – S0101, S0155, S0228, S0355, S0386, Sw24, Sw72, Sw240, Sw857, Sw936 and Sw951. The litter records included information on the total number of piglets born (TNB), number of piglets born alive (NBA), number of stillborn piglets (NSB), frequency of stillborn piglets (FSB), litter size at weaning (NW) in the first five parities. Individual heterozygosity estimates (for each microsatellite loci separately) and microsatellite multilocus heterozygosity (for all used loci) estimates (MLH) were used in our analysis. ANOVA was used to determine the relationship of the dependent effects (reproductive traits) to single locus heterozygosity using two classes: 0 (for homozygous individuals) and 1 (for heterozygous individuals). In addition, the following indicators were calculated for each genotype: the squared distances (d2) between alleles within an individual for each microsatellite loci and mean squared distances (mean d2) between alleles within an individual for 11 microsatellite loci. Spearman’s rank correlation coefficients were used to measure the association between d2 (for each microsatellite loci) and reproductive traits in sows. ANOVA on reproductive traits of sows belonging to different MLH and mean d2 classes was also undertaken. For sows from the Agricultural Private Enterprise “‘Techmet-Yug” were observed negative associations between heterozygosity and reproductive traits. We conclude that care should be taken when crossing between different breeders (English and Hungarian selection) to avoid outbreeding depression.

The application of phytobiotics in pig breeding

It is impossible to increase the productivity of pigs without organizing a complete balanced feeding, which provides not only a diverse set of feeds, but also stimulating feed additives and preparations. The purpose of the work was to study the effectiveness of the effect of the phytobiotic drug “Intebio” on the reproductive traits of sows and the productivity of the resulting young animals. The feed additive “Intebio” is a mixture of natural essential oils (eucalyptus, garlic, lemon and thyme), citric acid and filler (wheat bran or sunflower meal). It has been found that as a result of the use of the feed additive “Intebio”, the prolificacy of sows in the experimental group was 10,7 heads compared to 10,4 heads in the control group. The weight of piglets at the birth in the experimental group was 1,19 kg, which was 12,3 % higher than in the control group. The weight of the piglets litter at birth was statistically significantly higher in the experimental group 12,97 kg, compared to 11,35 kg in the control group. The livability of piglets for weaning in the experimental group was 100 %, and in the control group it was 93,9 %, the difference was 6,1 abs.%. The absolute weight gain in the live weight of piglets obtained during the experiment from 30 to 105 days in the control group was 26,97 kg, and in the 1st and 2nd experimental groups it was higher by 5,59 and 2,74 kg, respectively. Thus, the use of the phytobiotic feed additive “Intebio” in feeding of t sows in gestation period allowed to increase their prolificacy, the weight of piglets at the birth and their livability for weaning. The use of the feed additive “Intebio” as part of the diet of young pigs allowed to increase the absolute and average daily gains in the live weight of animals.

Experience in the use of probiotic drug in pig breeding

The results of research on the use of the probiotic drug “Profort” in the diet of young pigs have been presented in the article. The research was carried out under the conditions of LLC “Agrofirma Ariant” on the crossbreds of young pigs. The purpose of the research was to study the eff ectiveness of the effect of the probiotic drug “Profort” in intensive pig rearing on the reproductive traits of sows and the productive traits of piglets. In order to conduct the scientific and economic experiment at the first stage, 2 groups of pregnant sows were formed in each with 10 heads. The feeding and housing of the experimental animals were the same. In addition to the main diet the sows of the experimental group were fed the probiotic additive “Profort” at the dose of 500 g/t of feed for 30 days before and 30 days after farrowing. At the second stage the resulting young animals were divided into 3 groups. In addition to the main diet the young animals of the 1st experimental group have been received the probiotic drug “Profort” from 7 to 105 days together with compound feed. Piglets of the 2nd experimental group have been received the probiotic additive from 7 to 30 days. It has been found during of studies that as a result of the use of probiotic additive the prolificacy of sows in the experimental group was higher – 10,6 compared to 10,4 heads in the control group. The livability of piglets for weaning in the experimental group was 97,9 % compared to 93,9 % in the control group. The absolute gain in live weight of piglets from 30 to 105 days in the experimental groups was 34,94–36,98 kg, which was higher than in the control group by 7,9–14,2 %. In the blood of piglets of the experimental groups, the increase in the level of red blood cells, total protein, calcium and phosphorus has been noted.

Comprehensive evaluation of the productive and reproductive traits of sows of Yorkshire and Landrace breeds and their offspring

The purpose of the work was a comprehensive evaluation of the productive and reproductive traits of sows of Yorkshire and Landrace breeds and their offspring under the conditions of a breeding enterprise in the Republic of Belarus. During the studies of reproductive traits, it has been revealed that the highest rate of prolificacy among the evaluated breeds was distinguished by Yorkshire sows 14,0 heads for farrowing. In terms of milk content, Landrace sows were 2,5 kg or 4,57 % higher than Yorkshire sows. In terms of weight and socket weight per piglet at weaning at the age of 28 days sows Landrace piglets surpassed herdmates Yorkshire breed in the weight of the litter by 6,8 %, and the weight of one pig by 0,9 %. It has been found by the results of the evaluation of fattening and meat qualities of purebred young pigs that the best parameters were different gilts of Landrace breeds, whose age achieve the live weight of 100 kg was 163,1 days, and average daily gain of live weight – 864,8 g, which was higher than in young pigs of Yorkshire breed by 1,8 day or 1,09 %, and 28,9 g or by 3,46 %. The young pigs of Landrace breed has been characterized by the best values of the area of the “eye of loin” – 73,8 cm² and the highest yield and amount of meat – 68,5 % and 24 kg, which was 11,4 cm² or 18,2 % and 0,4 kg or 3,5 abs.%, respectively, higher than the herdmates of Yorkshire breed. The results obtained indicate the possibility of using boars and sows of Landrace and Yorkshire breeds not only in breeding, but also in industrial pig breeding.

THE LEVEL OF DISCRETION OF REPRODUCTIVE QUALITIES AND THEIR CORRELATION RELATIONS IN SOWS OF DIFFERENT INTERBREED DIFFERENTIATION ACCORDING TO SOME EVALUATION INDEXES

The article presents the results of studies of reproductive qualities of sows of different classes of distribution according to some evaluation indexes, the level of their discreteness and correlation. The study was conducted in agricultural enterprises of the Dnipropetrovsk region and the laboratory of animal husbandry of the State Institution «Institute of Grain Crops of NAAS of Ukraine». The work was performed according to the research program of NAAS №30 «Pigbreeding». Evaluation of sows for reproductive qualities was carried out taking into account the following characteristics: fertility, goal; high fertility, kg, milk yield, kg; nest weight at the time of weaning at the age of 28 days, kg, safety, %. The level of discrete features of reproductive qualities was calculated by the method of V. V. Seromolot, S. I. Svyatchenko (1984), indexes of reproductive qualities (I) – by the method of M. D. Berezovsky (quoted by P. A. Vashchenko, 2019), IRQ – according to the method of I. P. Sheiko and others (2006), biometric processing of research results – according to the methods of G. F. Lakin (1990). It is established that sows of the Large White breed of the controlled herd are characterized by high indicators of reproductive qualities. Taking into account the class of distribution of animals according to the index Berezovsky M. D. and the index of reproductive qualities of the sow (IRQ) a significant difference was found in fertility (4.1-4.2 goals), milk yield (23.5–23.7 kg) and nest weight at the time of weaning at the age of 28 days 25.2 kg). The discreteness factor (D) of reproductive traits in sows of the experimental groups ranged from 0.028 to 0.288. The number of significant correlation coefficients between the traits of reproductive qualities of sows and evaluation indices is equal to 90.00 %. The relationship between the index Berezovsky M. D. and the index of reproductive qualities of the sow (IRQ) is equal to 0.990 ± 0.0017 (tr=580.12; p<0.001). This indicates the effectiveness of their use in further breeding and breeding work with pigs of Large White breed. The use of sows of class M+ provides additional products at the level of +16.79–16.98 % or +421.06 -+416.35 UAH/head.

PSV-15 Genomic basis of reproductive performance in PRRSV-infected sows

Abstract Previous studies have shown that reproductive traits in sows during porcine reproductive and respiratory syndrome (PRRS) outbreaks are lowly heritable. However, little is known about the genomic basis of reproductive performance in PRRS virus (PRRSV)-infected sows. Thus, the objective of this work was to evaluate the genomic basis of reproductive performance in PRRSV-infected sows. Farrowing data from 475 Duroc and 405 Landrace sows that experienced a PRRS outbreak were used. Heritability and genome-wide association studies (GWAS) based on ~30K SNP genotypes were performed for each breed separately, for number of piglets born alive (NBA), stillborn piglets (NSB), mummified piglets (NM), piglets born dead (NBD; NSB+NM), total number of piglets born (TNB; NBA+NBD), and piglets weaned (NW). Heritabilities were estimated with ASReml using a model with the fixed-effect of parity and an animal random-effect, using a genomic-relationship matrix. GWAS was performed using Bayes-B in GenSel with a model fitting parity as fixed-effect and SNP effects as random. Heritability estimates (± standard error) for NBA, NSB, NM, NBD, TNB, and NW were 0.07±0.07, 0.02±0.11, 0.04±0.10, 0.08±0.08, 0.08±0.07, 0.06±0.04, respectively, for Duroc, and 0.09±0.07, 0.10±0.07, 0.10±0.08, 0.11±0.07, 0.07±0.08, 0.07±0.08, respectively, for Landrace. For Duroc, GWAS identified a quantitative trait locus (QTL) on chromosome (chr) 3 [114-120 megabases (Mb)] explaining 3.9% of the genetic variance (GV) for NBA, on chr 13 (189-193 Mb) explaining 2.7% GV for NBD, and on chr 5 (36-41 Mb) explaining 4.3% GV for TNB. For Landrace, GWAS identified a QTL on chr 13 (154-162 Mb) explaining 12.8% GV for NBA, on chr 14 (59-69 Mb) explaining 2.5% GV for NBD, and on chr 10 (7-9 Mb) explaining 4.1% GV for NW. These results indicate that reproductive traits are lowly heritable during a PRRS outbreak with few QTL identified in Duroc and Landrace sows.

Reproductive traits and blood biochemical parameters of sows when using a vitamin feed additive “LipoCar”

The reproductive traits of sows are of paramount importance in the production of high-quality pork. The world experience of pig farming shows the need to solve first of all the feed problem. Diets unbalanced in the content of vitamins restrain the manifestation of genetically inherent high prolificacy of sows. The purpose of the research was to study the influence of feeding the vitamin feed additive “LipoCar” on the reproductive traits of sows and the biochemical parameters of blood serum. The results of research on the introduction of vitamin feed additive “LipoCar” into the diet of pregnant sows have been presented in the article. The experiment has been carried out in the production conditions in JSC “Linevsky pedigree farm” on sows of Large White breed. Pregnant sows have received a basic diet, balanced for all the normalized elements of nutrition. Sows of the experimental group in the composition of the basic diet fed the feed additive “LipoCar”. The dosage of the drug “Lipocar” was 2,1 g/head/day. “Lipocar” has been fed for 20 days. The total duration of the experiment was 3 months. When introducing the vitamin feed additive “LipoCar” into the main diet of sows in the second half of pregnancy the increase in the number of piglets in the litter by 1,6-6,8 % and the weight of the litter – by 5,6-56,2 % (P ≤ 0,001) have been revealed in comparison with the control group of animals. There was a higher content of carotene in the blood serum of sows of the experimental group by 50,0 % (P ≤ 0,01), vitamin A - by 48,7 % (P ≤ 0,05), and total protein – by 4,9 % (P ≤ 0,05).

The effectiveness of a night shift when farrowing sows in reproduction farm LLC “Cherkizovo-Svinovodstvo”

The reproductive traits of sows are affected by many factors, so in the practice of work of reproduction farm should take into account the influence of each of the its in order to increase the output of piglets from the breeding stock, especially in industrial pig farms. The safe passage of farrowing has the big influence on the prolificacy of sows, since many piglets die directly during farrowing. Therefore, in modern industrial enterprises that use highly productive hybrid sows it is necessary to constantly monitor the passage of farrowing sows. Researches have been carried out in the reproduction farm of the pig breeding complex on the implementation of the night shift in the technological process at the farrowing site and its influence on the indicators of reproductive traits of sows of different age groups. The results of researches have shown that the implementation of the night shift in the reproduction farm of the industrial pig breeding complex using highly productive hybrid sows is necessary and economically has been justified. The prolificacy of sows of the 1st group was 12,9 piglets, and sows of the 2nd group by 0,6 % more. Per litter 1,25 stillborn piglets have been detected in the 1st experimental group of sows, while in the 2nd group there were by 0,25 piglets less. A total of 803 heads have been received in the 1st experimental group stillborn piglets, in the 2nd group 621 heads have been received or bys 182 heads less. When using the night shift in the 2nd group of sows additionally 182 piglets have been obtained. At the same time, the difference between the cost of additionally saved piglets and the cost of organizing the night shift for the two-week research period was 195,7 thousand rubles.

Live weight and livability of piglets received from sows with different duration of open days period and lactation

The most important element of pork production technology is the reproduction of the herd. Among all the reproductive traits of sows, there is a special emphasis on the heavy litter or live weight of piglets at birth, which largely determines the growth rate of young animals in further age periods. The livability of piglets ultimately determines how many young pigs will come to fattening and how much pork will be obtained. Therefore, the study of the reproductive traits of pigs is relevant for the theory and practice of pig breeding. The researches have been carried out under the environments of the reproductor of an industrial pig breeding complex, where the infl uence of the duration of the days open period and lactation of sows (suckling period) on their heavy litter and livability of piglets has been studied. The most signifi cant increase in sow fertility has been found, depending on the length of the days open period, when only one heat was missed. In the group of sows when weaning piglets at the age of 18, 21 and 24 days and the duration of the days open period of 21–28 days, the heavy litter was 0,054–0,197 kg more than when using sows with the days open period of 1–7 days. When inseminating sows with the days open period of 45 days or more compared to the group of sows with the days open period of 21–28 days, the increase in their heavy litter has not been observed. For example, the average heavy litter in the group of sows with the days open period of 45 days or more was 0,06 kg less than in sows with the days open period of 21–28 days. On average the groups of sows during insemination in the second heat after weaning piglets have shown the increase in heavy litter and livability of piglets compared to the group of sows without missing the heat. Sows inseminated in the second heat with the days open period of 21–28 days increased by 0.106 kg (P < 0,001) compared to the group of sows without heat missing. The researches have shown the increase in the livability of piglets in the groups of sows with the days open period of 21–24 and 45 days by more than 0,7–2,2 %, compared with the group of sows with the days open period of 1–7 days.

Phenotypic correlations between reproductive characteristics related to litter and reproductive cycle length in sows

The study estimated phenotypic correlations between reproductive traits in sows classified as maternal (Polish Large White, Polish Landrace, and Yorkshire) and paternal (Duroc, Berkshire, and Hampshire) components, kept on farms located in Poland and in the United States. Altogether, it used data on 736 litters from 196 sows to analyse traits related to litter and reproductive cycle length. The former included litter size, the numbers and the percentages of piglets born alive, stillborn, and weaned; the latter included gestation length, lactation length, and the lengths of weaning-to-conception, farrowing-to-conception, and farrowing intervals. The strongest positive correlations between the litter-related traits were those between litter size and the number of piglets born alive (0.90), the number and the percentage of piglets born alive (0.88), the numbers of piglets born alive and weaned (0.78), and litter size and the number of weaned piglets (0.68); the strongest negative correlations were between the percentage of piglets born alive and the percentage (−0.95) and the number (−0.82) of stillborn piglets. Among the traits related to reproductive cycle length, the strongest positive correlations were those between the length of weaning-to-conception interval and the lengths of farrowing-to-conception (0.96) and farrowing (0.97) intervals, and between the length of farrowing-to-conception interval and farrowing interval (0.98). Gestation length and lactation length were weakly negatively correlated (−0.25). Correlation coefficients between the traits related to litter size from one side and reproductive cycle length from the other were low and mostly statistically non-significant, suggesting that using phenotypic correlations can help improve economically important reproductive traits, but only within the two above-mentioned groups of traits.

Signs of reproductive qualities of sows of different types of adaptation, their variability and correlation

The results of studies of life expectancy and breeding use, as well as the main indicators of reproductive qualities of sows of large white breed of different types of adaptation, the economic efficiency of the research results and the level of correlation between traits are calculated cost-effectiveness of research results and the level of correlation between traits. The research was conducted in the conditions of agro-formations of Dnipropetrovsk region (LTD “Agro-Elita”, SLTD “Druzhba-Kaznacheevka”). The object of the study was sows of large white breed. Evaluation of sows of experimental groups (I – superadaptive, II – mediumadaptive, III – minusadaptive type of adaptation) according to the indicators of the level of adaptation and the main indicators of reproductive qualities were carried out taking into account the successor of quantitative traits: life expectancy, months, duration of breeding use, months, farrowing received, piglets total, head; live pigs obtained, naked; multiplicity, head; weight of the nest at the time of weaning at the age of 28–35 days, kg; duration of intergrowth, days. The adaptation level index and the coefficient of productivity were calculated according to the method of Smirnov V. S. (2003) and Long T. E., Short T. H., Bates R. O (2003) respectively. The economic efficiency of the research results was calculated by according to the indicator “mass of the nest at the time of weaning at the age of 28–35 days, kg”. Analysis of the research results shows that sows of superadaptive type will outperform peers of the opposite class (minusadaptive type) in terms of adaptation level and reproductive capacity by 58.36 and 43.63 % respectively. The proportion of indicator “duration of breeding use, months” to the indicator “life expectancy, months” in animals of superadaptive type is 81.8 ± 0.76 %, minusadaptive – 54.1 ± 2.67 % (lim = 27.7 %; td = 10.00; P < 0.001). An integrated assessment of sow reproductive performance by the performance factor confirms the superiority of sows of the superadaptive type to this group of animal traits of other adaptation types. The paired correlation coefficients between adaptation level indices and reproductive traits in sows of different types of adaptation range from -0.815 (tr = 6.45; adaptation level index × obtained farrowing) to +0.995 (tr = 45.05; life expectancy × duration of tribal use). In order to accelerate the breeding process and create a high-yielding herd of pigs, we suggest that the leading group of sows select animals with an index of “adaptation level” of 6.55–8.90 points.

Relationship between the testis size in male pigs and reproductive traits in their progeny

Selection for female farrowing performance is challenging to the swine industry due to the low heritability. Previous studies have suggested testis size as an indicator of reproductive performance. Thus, to determine the effectiveness of measuring testis size to identify sires of reproductive superior sows, 161 Yorkshire and Landrace boars were measured for width (TW) and area (TA). Farrowing performance was collected for 384 sows, daughters of 13 of the 161 boars. For heritability estimates (h2), the fixed effects of age (boar traits only), breed, contemporary group (CG), and parity (sow traits only), and the random effects of animal and permanent environment (sow traits only) were included in the model. Poisson phenotypic regression of the reproductive traits of daughters on the testis size of sires was performed including the fixed effects of parity, breeds of sow and sire, and TW or TA, and the random effects of sow and CG. For testis size, h2 were 0.69 and 0.66 for TA and TW, respectively. For reproductive traits, h2 ranged from 0.01 to 0.18. There were quadratic and linear relationships (P < 0.05) between reproductive traits in sows with TA and TW, respectively. Optimal performance for survival traits was obtained when TA of sires was within 17.2–18.5 cm2, which did not overlap with the range that resulted in greater mortality (15.8–16.3 cm2). With regards to TW, there was a linear increase of survival traits (P < 0.05) as TW increased, but not mortality (P ≥ 0.11). Phenotypic assessment of testis size of sires may be a useful tool to cull animals for breeding, improving female performance.

29 Late-Breaking: Genetic and phenotypic analysis of testis size in boars and reproductive traits in sows.

29 Late-Breaking: Genetic and phenotypic analysis of testis size in boars and reproductive traits in sows.

Analysis of Reproductive Characters in Hybrid Pig Combination (CLW x CL) x (D x Pn)

The aim of the experiment was to analyse reproductive characters in hybrid pig combination (CLW x CL) x (D x Pn). These reproductive traits of sows were studied: number of all, live born and weaned piglets, loses from live born piglets till weaning. These influences with an impact on reproductive characters were monitored: order of litter, number of piglets in a litter, birth weight of piglets, influences of sex and litter order on birth weight of piglets. An average number of all born piglets per sow and litter it was 13.25 piglets. From this an average number of live born piglets it was 12.48 piglets per sow and litter and from each litter there was 11.40 of weaned piglets. The highest number of live born piglets was reached in sows on the fourth litter – 14.50 piglets. On eighth and nineth litter fertility decreased to 11.60 and 11.00 piglets. Statistical conclusive difference (P ≤ 0.05) was found between fourth (14.50) and nineth (11.00) litter. Among birth weight in both sexes a statistical conclusive difference (P ≤ 0.05) was found. Higher birth weight (1.46 kg) was found in boars in comparison with gilts (1.40 kg). The highest birth weights in gilts were reached in litters of sows on the second and nineth litters – 1.49 kg and 1.48 kg. Birth weight decreased on tenth litter with average weight of 1.28 kg. The highest birth weight in boars was detected on the seventh litter but on the seventh litter piglets of only one sow were weightened so the result 1.67 kg is not objective. The second highest average birth weight was reached on the third litters – 1.53 kg. On the contrary the lowest average birth weight was on the fourth and tenth litters where boars reached weight of 1.28 and 1.25 kg. Statistical conclusive difference (P ≤ 0.05) was found between the second (1.53 kg) and tenth (1.25 kg) litter.

Influences Which Affect Reproductive Characters of Sows in Studied Reproductive Breeding

The aim of the study was to evaluate influences which affect reproductive characters of sows in chosen reproductive breeding. These reproductive traits of sows were studied: number of all, live born and weaned piglets, losses from live born piglets till weaning. These influences which affect reproductive characters were studied: order of litter, number of piglets in litter, birth weight of piglets and influence of sex on birth weight of piglets. An average number of all born piglets per litter it was 11.74 animals. From that 11.33 live born piglets per sow and litter. 10.15 piglets were weaned from each litter in average. It represents 11.68 % of losses in live born piglets till weaning. An influence of litter order on number of live born piglets in litter was studied in an experiment. The first litters show 11.36 of live born piglets in average, the second litters 10.38 piglets, the third litters 10.43 piglets and the fourth litters 10.75 piglets. Maximum was reached on fifth litter with 13.33 of live born piglets. From the sixth litter number of live born piglets was decreasing. On the sixth litter it was 12.33 piglets, on the seventh only 9.40 of live born piglets. Between fifth litter (13.33 piglets) and seventh litter (9.40 piglets) statistical conclusive difference (P ≤ 0.05) was found. The sixth litters showed the highest number of weaned piglets – 11.00. On the contrary the lowest number of weaned piglets it was on the seventh litter – 8.40 piglets. Statistical conclusive difference among the numbers of weaned piglets according to litter order it was not proved. Higher average birth weight (1.50 kg) was found in boars in comparison to gilts (1.46 kg). Next birth weight of gilts and boars was studied in dep endence on litter order. The lowest birth weight in both sexes was found on the first litters – gilts (1.27 kg) and boars (1.36 kg). Gilts reached the highest birth weights on the seconds and the sixths litters (1.62 kg). Statistical conclusive difference (P ≤ 0.05) was found in gilts among litters one (1.27 kg) and two (1.62 kg) respectively six (1.62 kg). Boars reached the lowest birth weight (1.36 kg) on the first litter. The highest birth weight of boars (1.73 kg) was reached on the fourth litter. Statistical conclusive difference (P ≤ 0.05) was found among these litters. Next statistical conclusive difference (P ≤ 0.05) was found between the first (1.36) and sixth (1.70 kg) litter and statistical conclusive difference (P ≤ 0.01) between the first and the second litter (1.68 kg).