Boar Breed Research Articles

30 Effects of using different dietary standardized ileal digestible lysine plans on growth performance and carcass characteristics of grow-finish pigs from high or low breeding value boars

Abstract The present study aimed to evaluate the impact of using different dietary standardized ileal digestible (SID) lysine (Lys) plans on growth performance and carcass characteristics of grow-finish pigs coming from high or low breeding value boars. A total of 2,080 pigs (PIC 800 × PIC Camborough) were housed in 20 mixed sex pens (26 pigs/pen), blocked by body weight (BW), and randomly allotted in a 2 × 2 factorial arrangement with boar breeding value (high or low) and nutrition Lys plan (current SID Lys curve recommendation for PIC 800 as % of PIC 337 SID Lys curve or alternative SID Lys curve). Pigs were weaned at 21 d of age (6.1 ± 0.05 kg BW) and followed during the wean-to-finish period until reach the market slaughter weight. Pigs were fed either the current recommendation or an alternative SID Lys curve for PIC 800, in a 6 phase feeding program: phase 1 (6-11 kg; 100 vs 100%, respectively); phase 2 (11-23 kg; 97 vs 100%, respectively); phase 3 (23-45 kg; 97 vs 100%, respectively); phase 4 (45-73 kg; 97 vs 95%, respectively); phase 5 (73-102 kg; 97 vs 95%, respectively); and phase 6 (102-132 kg; 97 vs 90%, respectively). Pigs were fed isoenergetic diets. Performance and carcass traits, and removals and mortality were recorded. Data were analyzed using mixed models in R, and considering pen as the experimental unit for performance traits and individual carcasses for carcass traits. There was no evidence of interaction between boar breeding value and nutrition plan factors. Overall, high breeding value pigs had greater average daily gain (ADG; 0.84 ± 0.005 g/d) compared with low breeding value pigs (0.82 ± 0.005 kg/d; P < 0.01), which was driven by increased average daily feed intake (ADFI; 1.92 ± 0.011 and 1.89 ± 0.011 kg/d, respectively; P < 0.05; Table 1). Moreover, high breeding value pigs had greater hot carcass weight (HCW; 97.8 ± 1.09 kg), carcass yield (74.1 ± 0.23%), backfat thickness (16.3 ± 0.29 mm) and lower lean meat % (57.0 ± 0.21%) compared with low breeding value pigs (96.0 ± 1.09 kg; 73.7 ± 0.23 %; 15.4 ± 0.28; 57.5 ± 0.21%, respectively; P < 0.05; Table 1). Regarding nutrition plan, no significant differences were observed for overall performance traits between pigs fed the current or alternative SID Lys curve (P > 0.05; Table 1). Nevertheless, pigs fed the alternative SID Lys curve had heavier HCW (97.3 ± 1.09 kg) compared with pigs fed the current SID Lys curve (96.6±1.09 kg; P < 0.05; Table 1). No significant differences were observed for overall removals and mortality by breeding value or nutrition Lys plan (P > 0.05). In summary, grow finish pigs from high breeding value boars have an improved productive performance. PIC 800 pigs may achieve the same productive performance with lower lysine levels at the end of the grow-finish period.

Motility-related microRNAs identified in pig seminal plasma exosomes by high-throughput small RNA sequencing

Boar fertility is a key determinant of the production efficiency of the whole pig breeding industry and boar sperm motility is the seminal parameter with the greatest impact on the fecundity of a sow. Exosomes are small, extracellular vesicles found in many body fluids. Seminal plasma exosomes, which are secreted by the epididymis, prostate, seminal vesicles, and testes, contain a large number of miRNAs, the types and levels of which can reflect the physiological state of source cells. It has been shown that the expression profile of seminal plasma exosomal miRNA differs between low-motility semen and normal semen. The aim of this study was to investigate the relationship between semen motility and exosomal miRNA profiles to obtain information that would allow to predict boar fertility, as well as contribute to the understanding of the mechanisms by which exosomal miRNAs regulate semen motility. Three high-motility (semen motility >90 %) and three low-motility (semen motility <80 %) semen samples were collected from Landrace and Yorkshire boars, respectively, and seminal plasma exosomes were extracted by ultracentrifugation. Exosome characterization was performed using transmission electron microscopy, NTA, and Western blot. The expression profiles of exosomal miRNAs associated with semen motility in the two boar breeds were subsequently determined by small RNA sequencing. The results showed that 297 known miRNAs and 295 novel RNAs were co-expressed in the four groups. Notably, six miRNAs (ssc-miR-122–5p, ssc-miR-486, ssc-miR-451, ssc-miR-345–3p, ssc-miR-362, and ssc-miR-500–5p) were found to be differentially expressed in both boar breeds. Enrichment analysis of the target genes of the differentially expressed miRNAs showed that they were mainly involved in biological processes such as regulation of transcription from RNA polymerase II promoter, regulation of gene expression, and intracellular signal transduction and signaling pathways such as the PI3K-Akt, MAPK, and Ras signaling pathways. The six differentially expressed miRNAs identified in this study have significant potential as noninvasive markers of boar semen motility. Meanwhile, the results of the enrichment analysis provide novel insights into the mechanisms underlying the regulation of semen motility.

PSV-20 Evaluation of Dietary Fiber Inclusion on Semen Production and Semen Characteristics in Mature AI Boars

Abstract This experiment was conducted at Purdue University swine research and education center. The objective of this study was to determine if the inclusion of fiber (8.48% vs 14.85% NDF) in the diet of boars influenced semen characteristics, concentration, motility, and morphology. Twenty-seven boars from two age groups (7 months and 18 months) and two genetic lines (maternal and terminal) were utilized in this study over a 12-week period with one week before the study data serving as a baseline for statistical analysis. Boars were blocked by age and breed and randomly allotted to receive 2.72 kg/d of corn-soybean meal diet (CON, n=13) formulated to meet NRC (2012) requirements or an isocaloric (estimated ME = 3,285 Kcal/kg) corn-soybean meal diet with 14.3% soyhulls and supplemental choice white grease (4.65%) inclusions (FIBER, n = 14). Semen was collected once per week per boar using the gloved hand method. While at the farm 3 mL of semen was mixed with 27 mL of extender (Androhep Plus, Minitube) to make a 1:10 dilution. The semen was then driven approximately 19 km to Purdue University where concentration (Nucleocounter SP-100), motility (Computer Assisted Sperm Analysis, CASA, CEROS II), and sperm cell morphology were analyzed. Statistical analyses were conducted using PROC MIXED in SAS 9.4 (Cary, NC), with the main effects of diet, age, and breed with week as a repeated measure. Significance was determined at P &amp;lt; 0.05 and a trend was observed at 0.05 &amp;lt; P ≤ 0.10. Fiber in the diet did not affect any semen characteristics throughout the study. However, the percent morphologically normal sperm was greater in young boars compared with the older boars (80.6% vs 74.1%, P = 0.0143) resulting from fewer head/tail abnormalities (1.8% vs 2.4%, P = 0.0249) and distal droplets (7.2% vs 9.6%, P = 0.0508). Maternal boars had fewer proximal droplets (6.9% vs 9.9%, P = 0.0325) and tended to have fewer head/tail abnormalities (1.8% vs 2.3%, P = 0.0800). Terminal boars tended to have fewer distal midpiece reflex abnormalities than maternal boars (3.3% vs 4.8%, P = 0.0948). Overall feeding boars a high fiber diet had no effect on semen characteristics; however there were effects of age and breed of boar on semen characteristics. Future research is needed with varying levels and types of fiber inclusion in the diet along with differing ages and breeds of boars to better understand how fiber may impact semen characteristics.

Inheriting the sins of their fathers: boar life experiences can shape the emotional responses of their offspring

IntroductionThe welfare of breeding boars is often overlooked, resulting in limited scientific data to foster discussion of the topic. We aimed to investigate the effect of different boar housing conditions on their offspring’s emotionality.MethodsEighteen boars were housed in three different conditions: crates (C; n = 6), pens (P; n = 6), or enriched pens (E; n = 6). Boars were distributed by semen quality (SQ; high, medium, or low). Three semen pools were used to inseminate 13 gilts housed in outdoor paddocks. At 25 days of age, 138 suckling piglets were subjected to open field (OF), novel object (NO), and elevated plus-maze (EPM) tests. Saliva was collected before and after the OF and NO tests to measure cortisol concentrations. At the end of the experiment, hair samples were collected for DNA paternity tests. Piglets were classified based on their behavioral responses using hierarchical cluster analysis of the principal components extracted from factor analysis of mixed data. The variables were reduced to seven principal components (dimensions, Dims), which explained 73% of the total variation, and were analyzed using linear mixed models. The models included each Dim as a dependent variable, paternal treatment and body weight (BW) as fixed effects, and paternal SQ as a random effect. Kruskal−Wallis and Wilcoxon rank-sum tests were used to compare the cortisol concentration ratios (before and after the OF and NO tests) between groups.ResultsThere was an effect of treatment on Dim 3 (EPM; activity/fear), with higher values in C piglets than E piglets (p = 0.047). Although C piglets had significantly higher values than P piglets in Dim 4 (EPM; anxiety; p = 0.029) and Dim 6 (NO; inactivity far from the object/exploration; p &amp;lt; 0.0001), the effect of the paternal treatment × BW interaction was significant in both dimensions (p &amp;lt; 0.05). The cortisol ratio in E piglets was greater than that in P and C piglets (p &amp;lt; 0.05).Discussion and conclusionOur findings indicate that boar breeding environments affect the stress response and emotionality (anxiety, fear, and exploration) of their offspring.

Peculiarities of the formation of sperm production and the course of peroxide oxidation in boars

The intensive use of boars and receiving biologically complete valuable ejaculates from them is possible due to early assessment of the quality of sperm production and timely determination of their genetic potential. The research aimed to determine the peculiarities of the formation of sperm production and the course of peroxide oxidation in boars during puberty. For the experiment, 5–10 month-old boars of Poltava Meat, the Large White, and Myrhorod breeds were used. The quality of the obtained ejaculates was evaluated according to standard indicators according to the instructions for artificial insemination of pigs. The research results indicate a significant increase in the quantitative indexes of sperm production in young boars in the age range with different features for each breed. By the eighth month of life, a general tendency to increase the parameters in the received ejaculates is noted. In contrast, the highest increase in ejaculate volume and sperm concentration was found in young boars of the sebaceous direction of productivity on the 240th day of the development (4.6 and 1.9 times). The minimum motility and survival of gametes were observed at five months, regardless of the breed, with a gradual increase to maximum values at the seventh and eighth months of age, depending on the direction of animal productivity. The use of moderate sexual load for young boars after they reach the age of 9 months ensures the functional activity of sperm suitable for artificial insemination (motility above 80 % and survival above 70 %). The significant changes in the pro-oxidant-antioxidant homeostasis in the sperm of boars of 7–8 months occur in the direction of the acceleration of the peroxygen oxidation of lipids, which is evidenced by an increase in the content of diene conjugates and TBC-active compounds and an increase in the activity of enzymes of the antioxidant link. An earlier formation of pro-oxidant-antioxidant homeostasis in this secretion is noted in representatives of the meat and fat direction of productivity. Thus, the obtained results indicate significant age-related changes in the ejaculate parameters and peculiarities of the course of peroxide oxidation processes depending on the breed of boars.

Dependence between behavioural acts and sperm parameters of boars of modern and local breeds of Ukraine

This study aimed to investigate the relationship between behavioural activities and sperm parameters in modern and local breeds of Ukrainian boars. Visual observations were conducted on 30 boars, aged 12 and 24 months, with five boars from each of the following breeds: Large White, Landrace, Ukrainian Meat, Pietrain, intrabreed type of Duroc breed of Ukrainian selection "Steppovyi", and the terminal line "Maxter". Behaviours such as rest, movement, feed, and water intake during 24 hours were recorded. Semen samples were manually collected from each boar and evaluated for quantitative and qualitative indicators of sperm quality and fertilizing capacity according to the "Instructions for Artificial Insemination of Pigs", which included parameters such as ejaculate volume, sperm concentration in the ejaculate, percentage of correctly motile spermatozoa, survival of spermatozoa, and fertilizing ability of boars. The study found that certain behavioural activities significantly influenced the qualitative and quantitative indicators of sperm parameters in boars of different breeds. Specifically, time spent on rest and movement, as well as the index of movement activity (at 12 months of age), significantly (P &lt; 0.05) influenced ejaculate volume, sperm concentration, and the percentage of correctly motile spermatozoa. Moreover, the effect of these behavioural acts on ejaculate volume had a curvilinear character. On the other hand, the survival of spermatozoa and fertilizing ability of boars were mainly determined by their time spent on feed and water intake (at 24 months of age), and the relationship detected in this case was asymptotic.

Gut microbial diversity among Yorkshire, Landrace and Duroc boars and its impact on semen quality

The gut microbiota plays an important role in pig health and performance, particularly in host growth and fecundity. In present study, the characteristics and diversity of gut microbiota in fine purebred boars from three-way crossbred “Duroc×Landrace×Yorkshire” pigs were investigated using 16 S rRNA gene sequencing. The results showed that the three breeds of boars shared similar gut microbiota, yet there remain slight differences at the family/genus level. At the family level, Ruminococcaceae, Streptococcaceae and Lactobacillaceae have the highest abundance in Landrace, while Rikenellaceae and f_p_251_o5 have the highest abundance in Duroc. The abundance of Prevotellaceae, Lachnospiraceae and Spirochaetaceae in intestinal of Yorkshire were higher than that of Landrace and Duroc. In addition, ten and six biomarkers were identified in the microbiota across breeds and months of age, respectively. Moreover, we evaluated the effect of gut microbiota on boar semen quality, revealing that Duroc had the strongest sperm vitality, significantly associated with the genus Rikenellaceae_PC9_gut_group. In addition, the spermatogenesis ability and sperm production improved gradually along with increase of age. In conclusion, this study provides a reference for understanding the gut microbiota composition of purebred boars used for three-way crosses and their impact on semen performance.

Semen production capacity among boar breeds and effect of organic antioxidant supplementation on sperm characteristics during the hot season in Thailand

Semen production capacity among boar breeds and effect of organic antioxidant supplementation on sperm characteristics during the hot season in Thailand

Genetic diversity of the Central European wild boar (Sus scrofa scrofa) population and domestic pig (Sus scrofa domesticus) breeds based on a microsatellite DNA locus.

The results of studies of the genetic structure of the Central European wild boar (Sus scrofa scrofa) population and four breeds of domestic pigs (Duroc, Yorkshire, Large White and Landrace) bred in the Central Black Earth region of Russia are presented in this work. Based on 12 microsatellite loci, a significant ( p <0.05) decrease in the level of genetic variability in bred breeds was shown. The expected heterozygosity and Shannon index were as follows: in the wild boar, Ho = 0.763 ± 0.026, I = 1.717 ± 0.091; in the Duroc breed, Ho = 0.569 ± 0.068, I = 1.191 ± 0.157; in the Landrace, Ho = 0.618 ± 0.062, I = 1.201 ± 0.147; in the Large White, Ho = 0.680 ± 0.029, I = 1.362 ± 0.074; and in the Yorkshire, Ho = 0.642 ± 0.065, I = 1.287 ± 0.156. The results of checking genotypic Hardy–Weinberg equilibrium based on the G-test of maximum likelihood demonstrated that the overwhelming majority of loci in the wild boar population were in the state of said equilibrium. By contrast, in pig breed populations, some loci demonstrated a significant deviation from the indicated equilibrium. In addition, the Yorkshire, Large White, and Landrace populations had loci, for which the hypothesis of neutrality was reliably rejected based on the results of the Ewens–Watterson test. The revealed private alleles, characteristic of the wild boar and breeds, can later be used to identify them. The ordination of the centroids of different herds in the space of the first two principal coordinates based on the matrix of pairwise estimates of Nei’s genetic distances showed that the most distant populations are the Duroc and Boar breeds, and the most genetically close are the Yorkshire and Landrace breeds. The closest to the wild boar population was the Large White breed. The assessment of the effective size, carried out using the method based on the linkage disequilibrium and the molecular coancestry method, showed that in all studied groups, including the wild boar population, the effective size was less than 100 individuals. The low effective size of the wild boar population (Ne = 21.8, Neb = 4.0) is probably caused by the death and shooting of animals due to Pestis africana suum.

Comparative Proteomics and Phosphoproteomics Analysis Reveal the Possible Breed Difference in Yorkshire and Duroc Boar Spermatozoa.

Sperm cells are of unique elongated structure and function, the development of which is tightly regulated by the existing proteins and the posttranslational modifications (PTM) of these proteins. Based on the phylogenetic relationships of various swine breeds, Yorkshire boar is believed to be distinctly different from Duroc boar. The comprehensive differential proteomics and phosphoproteomics profilings were performed on spermatozoa from both Yorkshire and Duroc boars. By both peptide and PTM peptide quantification followed by statistical analyses, 167 differentially expressed proteins were identified from 1,745 proteins, and 283 differentially expressed phosphopeptides corresponding to 102 unique differentially phosphorylated proteins were measured from 1,140 identified phosphopeptides derived from 363 phosphorylated proteins. The representative results were validated by Western blots. Pathway enrichment analyses revealed that majority of differential expression proteins and differential phosphorylation proteins were primarily concerned with spermatogenesis, male gamete generation, sperm motility, energy metabolism, cilium morphogenesis, axonemal dynein complex assembly, sperm–egg recognition, and capacitation. Remarkably, axonemal dynein complex assembly related proteins, such as SMCP, SUN5, ODF1, AKAP3, and AKAP4 that play a key regulatory role in the sperm physiological functions, were significantly higher in Duroc spermatozoa than that of Yorkshire. Furthermore, phosphorylation of sperm-specific proteins, such as CABYR, ROPN1, CALM1, PRKAR2A, and PRKAR1A, participates in regulation of the boar sperm motility mainly through the cAMP/PKA signal pathway in different breeds, demonstrating that protein phosphorylation may be an important mechanism underlying the sperm diversity. Protein–protein interaction analysis revealed that the 14 overlapped proteins between differential expression proteins and differential phosphorylation proteins potentially played a key role in sperm development and motility of the flagellum, including the proteins ODF1, SMCP, AKAP4, FSIP2, and SUN5. Taken together, these physiologically and functionally differentially expressed proteins (DEPs) and differentially expressed phosphorylated proteins (DPPs) may constitute the proteomic backgrounds between the two different boar breeds. The validation will be performed to delineate the roles of these PTM proteins as modulators of Yorkshire and Duroc boar spermatozoa.

Post-Thaw Sperm Quality and Functionality in the Autochthonous Pig Breed Gochu Asturcelta.

Simple SummaryGenetic resource banks were created to preserve the genetic material of endangered, rare, valuable individuals or genetically relevant breeds. Sperm cryopreservation is a practical and widespread strategy to preserve these genetic materials. This study aimed to characterize the frozen-thawed sperm of the native pig breed Gochu Asturcelta, considering the effects of boar age and season of semen collection on post-thaw sperm quality. We found that the boar age did not have a significant effect on the sperm parameters assessed. However, the season significantly affected many of these parameters (motility, viability, acrosomal status, mitochondrial activity). In general, sperm samples collected in spring and summer showed higher quality post-thawing, the lowest in winter. Our findings demonstrated that the post-thawing sperm quality of Gochu Asturcelta was in the range of results for commercial breeds, bringing a good prospect for the use of assisted reproductive technologies in this local breed.Genetic resource banks (GRB) preserve the genetic material of endangered, valuable individuals or genetically relevant breeds. Semen cryopreservation is a crucial technique to reach these goals. Thus, we aimed to assess the sperm parameters of semen doses from the native pig breed Gochu Asturcelta stored at the GRB of Principado de Asturias (GRB-PA, Gijón, Spain), focusing on intrinsic and extrinsic (boar, season) factors. Two straws per boar (n = 18, 8–71 months of age) were thawed, pooled, and assessed after 30 and 150 min at 37 °C by CASA (computer-assisted sperm analysis system; motility and kinematic parameters) and flow cytometry (viability, acrosomal status, mitochondrial activity, apoptosis, reactive oxygen species, and chromatin status). The effects of age, incubation, and season on post-thawing quality were determined using linear mixed-effects models. Parameters were on the range for commercial boar breeds, with chromatin status (SCSA: fragmentation and immaturity) being excellent. Incubation decreased sperm quality and functionality. The boar age did not have a significant effect (p > 0.05), but the between-boar variability was significant (p < 0.001). The season significantly affected many parameters (motility, kinematics, viability, acrosomal status, mitochondrial activity), especially after 150 min of incubation. In general, samples collected in spring and summer showed higher quality post-thawing, the lowest in winter. In conclusion, the sperm doses from the Gochu Asturcelta breed stored at the GRB-PA showed excellent chromatin status and acceptable characteristics after thawing. Therefore, boar and seasonal variability in this autochthonous breed could be relevant for cryobank management.

Органолептична оцінка м’яса різних генотипів свиней

The main indicators of the organoleptic assessment of muskulus longissimus dorsi of different genotypes of pigs in pure breeding, crossing and hybridization has been studies. Determination of indicators of organoleptic evaluation of muskulus longissimus dorsi was carried out by conventional methods. The materials of experimental studies were processed using methods of variation statistics. In pure-bred breeding for tenderness, color of muskulus longissimus dorsi in animals of the Landrass breed were characterized by the best indicators. Their advantage over their peers of the Large White breed was the following: in tenderness - 0.056 (group III, P>0.95)...0.044 kg/cm2, p. (IV group, P>0.99), in terms of color intensity - 5.0...9.2 extinction units, but no significant difference was found (P<0.95). Industrial crossing with the use of Landrass and Duroc boars made certain changes in the indicators of organoleptic assessment of the longissimus muscle dorsi. There was no significant difference in tenderness with the same «share of blood» for the Duroc and Landrass breeds. Crossbred animals of the indicated breeds of boars with a «blood share» ¾, compared with their peers with a «blood share» of ½, had more tender meat and the difference was 0.010 (Duroc breed, P>0.95) and 0.015 (Landrass breed, P>0.999). No significant differences between crossbred animals of different genotypes in color have been established. An increase in the «blood share» of the Duroc and Landrass breeds from ½ to ¾ contributed to an increase in the heterosis effect in tenderness by 1.5 (D)...2.3 % (L). In terms of color and boiling such a regularity was established in the descendants with a «share of blood» of the Duroc breed (1.4% and 2.4%, respectively). Hybrid animals obtained from the crossing of boars of the Poltava meat and Ukrainian meat breeds with the uterus of the large white breed had practically the same values in the tenderness of the longest muscle of the back. They also did not differ in the degree of boiling. Hybrid animals obtained from boars of the Ukrainian meat breed and raised in a specialized farm were characterized by a high value of the effect of heterosis in all indicators of organoleptic assessment, and those raised in a commercial economy were inferior to their peers with a «share of blood» of the Poltava meat breed in tenderness (by 0.4 %) and boiling (by 0.6 %).

Genetic diversity analysis in Chinese miniature pigs using swine leukocyte antigen complex microsatellites.

ObjectiveThe swine leukocyte antigen (SLA) gene group, which is closely linked and highly polymorphic, has important biomedical significance in the protection and utilization of germplasm resources. However, genetic polymorphism analyses of SLA microsatellite markers in Chinese miniature pigs are limited.MethodsEighteen pairs of microsatellite primers were used to amplify the SLA regions of seven miniature pig breeds and three wild boar breeds (n = 346) from different regions of China. The indexes of genetic polymorphism, including expected heterozygosity (He), polymorphic information content (PIC), and haplotype, were analyzed. The genetic differentiation coefficient (Fst) and neighbor-joining methods were used for cluster analysis of the breeds.ResultsIn miniature pigs, the SLA I region had the highest numbers of polymorphisms, followed by the SLA II and SLA III regions; the region near the centromere had the lowest number of polymorphisms. Among the seven miniature pig breeds, Diannan small-ear pigs had the highest genetic diversity (PIC value = 0.6396), whereas the genetic diversity of the Hebao pig was the lowest (PIC value = 0.4330). The Fst values in the Mingguang small-ear, Diannan small-ear, and Yunnan wild boars were less than 0.05. According to phylogenetic cluster analysis, the South-China-type miniature pigs clustered into one group, among which Mingguang small-ear pigs clustered with Diannan small-ear pigs. Haplotype analysis revealed that the SLA I, II, and III regions could be constructed into 13, 7, and 11 common haplotypes, respectively.ConclusionThis study validates the high genetic diversity of the Chinese miniature pig. Mingguang small-ear pigs have close kinship with Diannan small-ear pigs, implying that they may have similar genetic backgrounds and originate from the same population. This study also provides a foundation for genetic breeding, genetic resource protection, and classification of Chinese miniature pigs.

Analysis of differentially abundant proteins related to boar fertility in seminal plasma using iTRAQ-based quantitative proteomics

Animal fertility is one of the most important characteristics for the livestock breeding industry. Conventional semen analysis provides basic information on sperm quality, but the predictive value of such analysis with regard to fertility remains questionable. Therefore, it is important to determine and predict male fertility more accurately in the clinic. To identify seminal plasma proteins involved in fertility, isobaric tags for relative and absolute quantitation (iTRAQ) and liquid chromatography with tandem mass spectrometry (quantitative proteomic analysis) were used to identify differentially abundant proteins (DAPs) in seminal plasma between high- and low-reproductive-efficiency Landrace boars. A total of 141 DAPs were identified, of which 125 upregulated and 16 downregulated proteins were subjected to bioinformatics analysis. These DAPs were found to be mainly involved in proteolysis, ATP binding, and energy metabolism. We investigated the relevance of three DAPs—ceruloplasmin, carboxypeptidase E (CPE), and serpin family A member 12 (SERPINA12)—in an in vitro fertility assay. This assay revealed that the inhibition of these proteins with antibodies can reduce or increase the fertilization rate. These results indicate possible biomarkers for the selection of high-fertility boars and provide a theoretical basis for the use of protein biomarkers in the livestock breeding industry. SignificanceOur study identified differentially abundant proteins in the seminal plasma of high-reproductive-efficiency and low-reproductive-efficiency Landrace boars. These proteins may be used as biomarkers to screen out high-fertility boars. The study can provide not only a new method for improving the effects of artificial insemination and reproductive efficiency of boars but also an important reference for boar breeding. Meanwhile, because pigs and humans have similar physiological parameters and organ sizes, our findings can also serve as a reference for human reproduction research.

Functional endocrine reserves of testes of boars of different breeds and indicators of their sperm

It is difficult to objectively assess the functional state of the endocrine gland based on the level of hormones in the blood, since hormones vary significantly in absolute values during the day. Therefore, to assess the functional state of the endocrine glands in biological and medical practice, "load" is used. The criterion for evaluating the state of the gland is the change in the concentration of secreted hormone by the endocrine gland in response to the stimulation. As is known, the testis reacts relatively quickly to stimulation with chorionic gonadotropin. This allows us to determine the limiting features of the hormone-synthesizing and hormone activity of the testes and determine the maximum response of the testes to this stimulation. The object of the study was 6-month-old boars of large white breed, Landrace and tempo, 10 heads from each breed. In order to determine the functional endocrine reserves of the testes at 6 months of age, CG (chorionic gonadotropin) was administered intramuscularly at a dose of 1000 IU. HCG was administered 3 times every 72 hours. Blood for the determination of testosterone was taken before administration of HCG and 2.12,24,48 and 72 hours after its administration. Testosteron was determined by the enzyme immunoassay. Sperm counts in 18-month-old boars were studied using standard methods. Performed three-fold loads with an interval of 72 hours showed that the hormone level increased to 7.2±0.6 nmol/l in a large white breed 72 hours after the first administration of HCG, in the Landrace breed to 7.9±0.5 nmol/l, in the Duroc breed to 7.0±0.7 nmol/l, in the tempo breed to 7.0±0.6 nmol/l. After the second injection HCG the testosterone levels in large white breed boars increased by 1.2 nmol/l, and breeds Duroc 1.7 nmol/l, Landrace 0.1 nmol/L. In the boar breed, tempo increased the hormone by 0.4 nmol/l. In this regard, the increase in testosterone in experimental boars continued, which means that the reserves of endocrine function of the testes were not fully realized, so the 3rd stimulation of HCG was also performed. In a large white breed of boars and Duroc, the maximum concentration of testosterone was observed 24 hours after administration of HCG and was 9.2±0.7 and 8.9±0.5 nmol/l respectively. In the Landrace and tempo breeds, the maximum concentration of testosterone was 2 hours after 3 CG stimulation and was 8.2±0.6 and 7.5±0.6 nmol/l. respectively. In terms of sperm, its fertilizing capacity and the production of live piglets per Farrow, the indicators were higher for boars of large white breed and Duroc.

The Endocrine Function of Testes in 12- and 18-Month-Old Boars of Different Breeds.

Testes have several primary functions, such as male gametes production (spermatozoa) and secretion of several endocrine factors, including the production of steroid and protein hormones which facilitate elements in the healthy reproductive function of mammals. The potential of an animal functional endocrine reservoir could be an interesting finding in animal reproduction management. Therefore, the current study aimed to analyze the functional endocrine reserves of testes in 12- and 18-month-old boars of four different boar breeds, namely Large White, Landrace, Duroc, and Tempo, as the animal model in this research (n=10). To determine the functional endocrine reserves of the testes at 12 and 18 months of age, boars received injections of human chorionic gonadotropin (hCG) 3 times every 72 hours. Testosterone was measured in blood samples (10 mL) taken from the jugular vein before the administration of hCG as well as 2, 12, 24, 48, and 72 hours after administration of each of three hCG injections. The index of endocrine activity of the testes was determined by the formula: Ita = T1 -T0 / T0 , where Ita is the index of endocrine activity of the testes, T0 is the testosterone concentration before the administration of hCG, and T1 is the maximum testosterone concentration after the third administration of hCG. The effects of the hCG injection on boar testes at different age periods indicated that the testes of Large White and Duroc boars have higher potential endocrine reserves compared with the Landrace and Tempo breeds.

Developmental Rule and Correlation of Testicular and Semen Quality in Different Breeds of Boars

Developmental Rule and Correlation of Testicular and Semen Quality in Different Breeds of Boars

Influence of Collection Frequency on Boar Ejaculate Quality Parameters

The aim of study was to examine the effect of the boar ejaculate collection frequency on the parameters of its quality. The research covered a three-year period, and four most common boar breeds in our area. A total of 1705 ejaculates were taken from Yorkshire boars, 1693 ejaculates from Landrace boars, 1106 ejaculates from Pietrain boars and 669 ejaculates from Duroc boars. Within each breed, groups were formed according to the frequency of ejaculate taking (once, twice, three, four, five, or six times a month). Evaluation of ejaculate quality was performed in a reprocentre laboratory, according to their quality standards. Quality parameters that have been determined were the volume of ejaculate, sperm concentration, progressive sperm motility, live sperm count, the number of doses per ejaculate and the overall assessment of ejaculate. Results of this study show that the volume and progressive motility increase with the increase of frequency in ejaculate taking, while the sperm concentration drops, except for the Pietrain boars. The best results were observed in ejaculates collected 5-6 times during the month. The highest mean volume of ejaculate was found in the Landrace boars (292.22 ml), in ejaculate taking frequency of five times per month. The highest average progressive sperm motility was 92% in the Yorkshire boars, on collection frequency of six times a month, while the highest concentration of spermatozoa was found in the Duroc boars in collection frequency of one taking per month (447.32 mil/ml). The results of this study indicate that the frequency of ejaculate taking affects the boar semen quality parameters.

Analysis of biomarkers for prediction of idiopathic infertility in Large White Yorkshire boar (Sus scrofa domesticus)

The experiment was conducted to analyze biomarkers like pH, calcium (Ca2+), cholesterol (Ch), estradiol (E2) and vitamin D (Vit-D) in the serum for prediction of idiopathic infertility and its early amelioration. pH of epididymal luminal fluids (ELF) and concentrations of Ca2+, Ch, E2 and Vit-D were measured in serum, as well as in epididymal luminal fluids (ELF) and sperm cytosolic fluids (SCF) from caput, corpus and cauda epididymis of healthy, mature Large Yorkshire breed of boar (n=100). The levels of these bio-molecular components in the serum, in ELF and SCF from different epididymal segments were used statistically to develop a Curve Fit Regression Equations and a prediction equation to predict the quantum of these bio-molecules in the ELF and SCF by estimating their levels in the serum which would have been very difficult otherwise to be estimated in live animals. Further, from the clinical point of view, present findings about the spermatozoa maturation can pave the way for development of specific marker(s) that will assist in the development of new arena for both the prediction and early diagnosis of male infertility and for improving treatment modalities of male infertility, since epididymal dysfunctions are related to cases of idiopathic male infertility.

The influence of boar breed and applied method on the meat content

The aim of this study was to determine the influence of the applied method of the quality carcass in 201 descendants, both sexes (n=108 male castrated animals and n=93 females), of studied boar-sires. For the determination of the meat yield (JUS1) and the share of meat (JUS 2) in carcass sides, on the basis of the performed measurements, tables for meat pigs, which are an integral part of the Rulebook on the quality of slaughtered pigs and categorization of pork meat (OG SFRY, 1985), were used. Share of meat (EC 94 and EC 06) was determined on cooled left carcass sides by method of partial dissection (according to methodology recommended by EU- Walstra and Merkus, 1996). Research was carried out on pig farm and in experimental slaughterhouse of the Institute for Animal Husbandry, Belgrade-Zemun. Housing, care and nutrition of animals were in accordance to breeding technology in investigated herd. The average share of meat determined by the application of the Rulebook (JUS2) was 43.58% with a lower absolute variation compared to the EU regulation from 1994 (EC 94; 53.56%) and from 2006 (EC 06; 56.55%). The estimated lean meat content by the application of the Rulebook (JUS 2) was by 9.98% lower compared to the EC 94 regulation and by 12.97% lower compared to EC 06. If we are talking about the selection of offspring for breeding, if we consider only the estimated leanness, we see that within the Landrace (L) breed we have high and very significant (P&lt;0.001) differences between the sires for the assessed meat content according to EC 94 and EC 06. By implementing new methods of assessment of lean meat content (EC 94 and EC 06), a higher share of meat (9.98% respectively 12.97%) was determined compared to the Rulebook (1985). This research indicates the necessity of changing the current method for the establishment of meat content of pigs in the Republic of Serbia.