Boar Effect Research Articles

Expansion of native wild boar populations is a new threat for semi-arid wetland areas

Wildlife management and conservation requires monitoring of species distribution and population indicators, especially when the unbalanced demographic changes of some species can affect the whole ecosystem functioning. The populations of wild boar (Sus scrofa) have, over the past few decades, undergone an expansion around the world, reaching situations of overabundance that can cause serious economic, ecological and health problems. This numerical increase of wild boar and its new spatial invasion can affect certain vulnerable species in sensitive ecological zones, such as the main inland wetland complex in SW Europe.In this context, we aim to (i) examine the association of wild boar abundance and that of lagomorphs, and waterbird productivity, controlling the possible effects of wild carnivores and other environmental predictors, and (ii) applying a survey method useful for managers to evaluate expected effect of wild boar abundance.Overall, the presence of wild boar has been detected in 80.8% of the monitored wetlands (n = 26), but a high variation of abundance rates was found. Wild boar abundance negatively associated with the productivity of the entire community of waterbirds, a priori highly vulnerable, breeding on shores or islands, both colonially (genus Gelochelidon, Himantopus, Recurvirostra, Sternula, Glareola, Tringa and Phoenicopterus) or solitary (genus Anas, Spatula, Mareca, Charadrius, Vanellus, Anser, Ardea, Aythya, Fulica, Netta, Oxyura and Tadorna).In addition, we evidenced a clear negative association of wild boar and wild rabbit (Oryctolagus cuniculus) population abundance in the monitored wetlands. Rabbits are a keystone species in the study area and represent stable prey for many endangered predators.Our results suggest that potential impacts caused by high wild boar abundance may be already reaching unsustainable levels for some wetlands. Inter-species integrated monitoring is key to address the population management plans of wild boar populations in wetlands and to preserve the most vulnerable species.

Seasonal Changes of Nuclear DNA Fragmentation in Boar Spermatozoa in Spain.

Simple SummaryArtificial insemination is widely used in pig production and currently a boar performs several thousand matings per year. Traditionally sperm quality is focused on the number of spermatozoa, their motility and morphology. However, the quality of sperm DNA, which contains genetic information, is also related to fertility problems. The aim of this research was to study the effect of natural light hours and age of the boar on the status of the sperm DNA. After a powerful statistical analysis, it was found that the percentage of spermatozoa with fragmented DNA decreases within the observed age range as the boar gets older. On the other hand, the amount of spermatozoa with fragmented DNA was the lowest in autumn while it was the highest in summer. This study demonstrates the remaining seasonality of boars in Spain and highlights the importance of controlling the environmental conditions in the farms. Sperm DNA testing provides a basis for improving the selection of AI boars by excluding males with higher DNA fragmentation due to their very young reproductive age that may pose a potential subfertility.There are numerous cases when conventional spermiogram parameters are all within an acceptable range but boar subfertility persists. The total sperm nuclear DNA fragmentation index (tDFI) is a trait related to fertility and prolificacy problems that is not routinely evaluated in commercial AI boars. The aim of this research was to study the effect of the photoperiod, season and reproductive age of the boar on tDFI (measured by SCSA) of 1279 ejaculates from 372 different boars belonging to 6 different breeds located in 6 AI studs in Spain. tDFI data ranged from 0.018% to 20.1%. Although there was a significant single boar effect in the tDFI occurrence, a negative correlation between the tDFI and the age of the boar was found (p < 0.001). tDFI would decrease due to aging of the boar 0.66% each year old within the observed age range. After including age as a covariate in the ANCOVA, no differences were found in tDFI between photoperiods when the sperm collection date was evaluated. However, when the date of the production of semen in the testis was evaluated, the total percentage of spermatozoa with fragmented nuclear DNA was 1.46% higher in the increasing photoperiod in comparison to the decreasing photoperiod (p < 0.0001). On the other hand, for both dates, the lowest tDFI values corresponded to minimum day length for decreasing photoperiod phase (autumn), while the highest tDFI values were found in summer (maximum day length for decreasing photoperiod phase).

The effects of boar on susceptibility to swine inflammation and necrosis syndrome in piglets

Inflammation and necrosis can appear in pigs in several parts of the body simultaneously. The signs can affect newborns, suckling piglets and older pigs, and recent studies suggest that the syndrome is primarily endogenous. Inflammation and necrosis indicate impaired animal welfare, and thus should be controlled in pig production. This can be achieved by improving husbandry conditions. However, the variation in signs also appears to have a genetic component. The aim of the present study was therefore to test the effects of different boars from the Duroc and Pietrain breeds on the prevalence of swine inflammation and necrosis syndrome in their offspring. For this purpose, 646 suckling pigs from 39 sows (two herds) and 19 boars were made available. On the third day of life, the piglets were examined for clinical signs of inflammation and necrosis at tail base, tail tip, ears, face, teats, navel and claws. For the evaluation, we included the boar within the breed and the breed as fixed effects and the sow within the herd as random effects. More than 70% of the piglets were affected at the tail base, ears, coronary bands and heels. Bristle loss, swelling, redness, venous congestion and claw wall bleeding occurred most frequently. Exudation and necrosis affected fewer piglets. None of the piglets was completely free from signs of SINS. Offspring from Duroc boars had significantly lower SINS scores (4.87 ± 0.44) than offspring from Pietrain boars (10.13 ± 0.12). Within the Pietrain breed, significant effects of the boar were observed on inflammation and necrosis levels. Under the present study conditions, using Duroc boars instead of Pietrain boars resulted in a 59% reduction in the SINS scores of their offspring. The SINS score in the offspring of the most favourable Pietrain boar was almost 40% lower than that of offspring in the least favourable. These findings confirm considerable genetic effects on the outcome of SINS under a given husbandry. Further studies are necessary to characterise the genetic effects in detail and to make them useful to combat the syndrome.

Steroidome and metabolome analysis in gilt saliva to identify potential biomarkers of boar effect receptivity

Optimal management of gilt reproduction requires oestrus synchronization. Hormonal treatments are used for this purpose, but there is a growing demand for non-hormonal alternatives, especially in organic farms. The boar effect is an important alternative opportunity to induce and synchronize oestrus without hormones. Before puberty, gilts exhibit a ‘waiting period’ during which boar exposure could induce and synchronize the first ovulation. We searched for salivary biomarkers of this period of boar effect receptivity to improve detection of the gilts to stimulate with the perspective of enhancing the efficacy of the boar effect. Saliva samples were collected from 30 Large-White×Landrace crossbred gilts between 140 and 175 days of age. Gilts were exposed twice a day to a boar and subjected to oestrus detection from 150 to 175 days of age. Among the 30 gilts, 10 were detected in oestrus 4 to 7 days after the first introduction of the boar and were considered receptive to the boar effect, 14 were detected in oestrus more than 8 days after first boar contact, and six did not show oestrus and were considered non-receptive. Saliva samples from six receptive and six non-receptive gilts were analyzed for steroidome and for metabolome using gas chromatography coupled to tandem mass spectrometry and 1H nuclear magnetic resonance spectroscopy, respectively. Four saliva samples per gilt were analyzed: 25 days and 11 days before boar introduction, the day of boar introduction, 3 days later for receptive gilts or 7 days later for non-receptive gilts. Twenty-nine steroids and 31 metabolites were detected in gilt saliva. Salivary concentrations of six steroids and three metabolites were significantly different between receptive and non-receptive gilts: progesterone and glycolate 25 days before boar introduction, 3α5β20α- and 3β5α20β-hexahydroprogesterone, dehydroepiandrosterone, androstenediol, succinate, and butyrate 11 days before boar introduction, and 3β5α-tetrahydroprogesterone on the day of boar introduction. Thus, nine potential salivary biomarkers of boar effect receptivity were identified in our experimental conditions. Further studies with higher numbers of gilts and salivary sampling points are necessary to ascertain their reliability.

Recent advances in boar semen cryopreservation

Since 35 years ago boar semen has been frozen and used for artificial insemination (Al). However, fertility of cryopreserved porcine sperm has consistently been low as boar sperm are more sensitive to cellular stress imposed by changing osmotic balance, oxidative stress, low-temperature exposure, cryo-protectant intoxication etc. and are less able to compensate for these deficiencies at commercially applicable dosages. Additionally, differences in sperm freezability among individuals are well known. Here we review current advances on tests to screen sperm quality post-thaw, on ways of diminishing individual boar effects, on improvement of cryoprotection by novel extender components, on packaging and freezing protocols and freezing and thawing methods, and on the handling of sexed boar sperm. Major advances have been registered, which have improved cryo-survival and the capacity to process boar semen for commercial Al.

Who's afraid of the big bad boar? Assessing the effect of wild boar presence on the occurrence and activity patterns of other mammals.

Wild boar are considered one the world's worst invasive species and linked to biodiversity loss, competition for resources, predation of native species, and habitat modifications. In this study, we use camera traps to evaluate whether the invasive wild boar had an effect on the medium-sized mammal community of a protected area in southern Brazil. Based on photographic records, we evaluated whether the presence and relative abundance of wild boar was associated with a decrease in diversity or change in activity of medium-sized mammals. All comparisons were made between samples where wild boar were present or absent. The records of each camera during a season were considered a sample. The wild boar was the fourth most common species in the study area being present in 7.8% of the photographic records. The species richness of mammals was not negatively affected by the occurrence of wild boar and most common species did not exhibit changes in the daily activity pattern. However, we recorded an increase in the time elapsed between an observation of wild boar and the record of the next species relative to the average latency period observed among other mammalian species. This average latency period was similar to that observed in the case of large predators such as Puma, and its increase could be reflective partly of the avoidance of native species to wild boar. Nevertheless, our results show that the effect of invasive wild boar on the mammal community is not large as expected.

Accounting for detection unveils the intricacy of wild boar and rabbit co-occurrence patterns in a Mediterranean landscape

The patterns of species co-occurrence have long served as a primary approach to explore concepts of interspecific interaction. However, the interpretation of such patterns is difficult as they can result from several complex ecological processes, in a scale-dependent manner. Here, we aim to investigate the co-occurrence pattern between European rabbit and wild boar in an estate in Central Portugal, using two-species occupancy modelling. With this framework, we tested species interaction for occupancy and detection, but also the interdependencies between both parameters. According to our results, the wild boar and European rabbit occurred independently in the study area. However, model averaging of the detection parameters revealed a potential positive effect of wild boar’s presence on rabbit’s detection probability. Upon further analysis of the parameter interdependencies, our results suggested that failing to account for a positive effect on rabbit’s detection could lead to potentially biased interpretations of the co-occurrence pattern. Our study, in spite of preliminary, highlights the need to understand these different pathways of species interaction to avoid erroneous inferences.

Wild boar grubbing causes organic carbon loss from both top- and sub-soil in an oak forest in central China

Soil disturbances by large animals are known to affect soil carbon (C) storage and thus have the potential to change ecosystem functioning in forests. However, little is known about the effects of wild boar grubbing on soil CO2 emission in forest ecosystems. Here we investigated soil respiration and soil physico-chemical properties of top- (0–10 cm) and sub-soil (10–20 cm) on the paired grubbed and non-grubbed plots in an oak forest for a 2-year period. Wild boar grubbing substantially increased soil respiration by 69.5% in 2015 and 32.9% in 2016, respectively. Wild boar disturbance considerably elevated soil basal respiration but showed no effect on its temperature sensitivity. In addition, we found that the grubbing-induced increases in soil organic carbon and microbial biomass activity from both top- and sub-soil contributed to the stimulated soil respiration after the disturbance. Our 2-year experiment indicates that soil bioturbation could lead to a strong positive effect on soil CO2 emission in oak forest ecosystems, but the stimulation tends to reduce with recovery time. The finding also highlights the importance of soil depth and time effect while quantifying the effect of wild boar grubbing on soil C storage in forest ecosystems.

PSIII-11 Semen quality effect on conception rate among three purebred swine lines

Abstract The objective of this study was to examine the relationship between semen quality and conception rate. There were 30985 Duroc, 15888 Landrace, and 18198 Yorkshire single sire, purebred mating observations with 880 Duroc, 508 Landrace, and 492 Yorkshire boars represented from March 2011 to July 2018. Data from each breed was analyzed using a logistic regression model with fixed effects of sow parity at time of mating, the number of breeding attempts for the sow, days rest of the boar, and days from collection to insemination, covariates of age at collection, motility, percent abnormal tails, and random effects of contemporary group, boar, and evaluator. For Duroc, increased percent abnormal tails decreased conception rate (odds ratio=0.99, P &lt; 0.05), and more than 9 days rest resulted in lower conception rates compared to less than 5 days rest (odds ratio=0.85, P &lt; 0.05). For all three breeds, inseminations occurring 2 days post-collection tended to result in lower conception rate compared to 1 day post-collection (Duroc, odds ratio=0.94, P &lt; 0.1, Yorkshire, odds ratio=0.87, P &lt; 0.1, Landrace, odds ratio=0.91,P &lt; 0.05); however, for Landrace, inseminations occurring 4 days post collection resulted in higher conception rates compared to 1 day post-collection (odds ratio=1.16, P &lt; 0.05). For Yorkshire, increased motility was associated with higher conception rates (odds ratio=1.02, P &lt; 0.001). The effect of age at collection on conception rate was small, but significant for both Landrace and Duroc resulting in ~1% increase per year of age (P &lt; 0.05). Boar and semen quality effects on conception rate were inconsistent across breeds, suggesting that optimizing conception rates across breeds could be difficult.

Evolution of steroid concentrations in saliva from immature to pubertal gilts for the identification of biomarkers of gilts receptivity to boar effect

Estrus synchronization is necessary for management of gilt reproduction in pig farms. It is usually achieved by using synthetic progestagens, but there is increasing demand for non-hormonal alternative tools with the prospect of sustainability of livestock production. Moreover, in organic farms, synthetic hormones are not allowed. Before reaching puberty, gilts exhibit a “waiting period” during which external stimulations, such as boar exposure, could trigger and synchronize the first ovulation. However, practical non-invasive tools for detection of the “waiting period” in pig farms are lacking. During this period, estrone levels in urine are high, but urine sampling is difficult in group-housed females. Our objective was to identify among steroids potential biomarkers of this “waiting period” through saliva monitoring from immature to pubertal gilts using gas chromatography coupled to tandem mass spectrometry.Starting between 144 and 147 days of age, six Large White gilts were submitted to ultrasound puberty diagnosis 3 times a week until first ovulation. Urine and saliva samples were collected to analyze weekly estrone and steroidome respectively, until puberty. Urinary estrone concentration significantly increased 2 weeks before first ovulation occurring between 182 and 192 days of age. The period with increasing estrone levels was considered as the “waiting period”. Steroidome analysis allowed identifying and quantifying 28 steroids in 500 µl of gilts saliva. Significant decrease of dehydroepiandrosterone and significant increase of 5α-dihydroprogesterone and 17β-estradiol were detected 2 weeks before puberty, suggesting that these steroids could be potential biomarkers of the “waiting period”.These results show that painless sampling of saliva could be a non-invasive welfare-friendly tool for the identification of the physiological hormonal status of the gilts and possibly the optimal time for application of the boar effect, a solution to synchronize puberty without exogenous hormones.

Salivary and urinary metabolome analysis for pre-puberty-related biomarkers identification in porcine

Estrus synchronization is important for optimal management of gilt reproduction in pig farms. Hormonal treatments, such as synthetic progestogens, are used on a routine basis, but there is a growing demand for non-hormonal alternative breeding tools. Before puberty, gilts exhibit a ‘waiting period,’ related to the ovarian development and gonadotrophin secretions, during which external stimulations, such as boar exposure, could induce and synchronize first ovulation. Practical non-invasive tools for identification of this period in farms are lacking. During this period, urinary oestrone levels are high, but urine sampling is difficult in group-housed females. The aim of this work was to search for specific biomarkers of the ‘waiting period’ in saliva and urine. In total, nine 144- to 147-day-old Large White gilts were subjected to trans-abdominal ultrasonography three times a week for 5 weeks until puberty detection (week –5 to week –1 before puberty). Urine and saliva samples were collected for oestrone assay to detect the ‘waiting period’ and for metabolome analysis using 1H-nuclear magnetic resonance spectroscopy to detect potential biomarkers of the ‘waiting period.’ Gilts were slaughtered 7 days after puberty detection for puberty confirmation. Results were consistent with ultrasonography data for six gilts. Urine and saliva samples from these six gilts were analyzed. Urinary estrone concentration significantly increased 2 weeks before puberty detection. Metabolome analysis of urine samples allowed the identification of 78 spectral bins, among them, 42 low-molecular-weight metabolites were identified. Metabolome analysis of salivary samples allowed the identification of 59 spectral bins, among them, 23 low-molecular-weight metabolites were detected and 17 were identified. No potential biomarker was identified in urinary samples. In saliva, butyrate and 2HOvalerate, 5.79 ppm (putatively uridine), formate, malonate and propionate could be biomarker candidates to ascertain the pre-puberty period in gilt reproduction. These results confirm that non-invasive salivary samples could allow the identification of the physiological status of the gilts and presumably the optimal time for application of the boar effect. This could contribute to synchronize puberty onset and hence to develop non-hormonal breeding tools.

The effect of DanAvl Duroc and Pulawska boars in crossbred with DanAvl Hybrid on meat quality of finishing pigs

The research was aimed at determining the physicochemical and sensory properties of the m. longissimus lumborum at DanAvl Hybrid (Landrace – Yorkshire) fatteners and derived from DanAvl Hybrid sows and DanAvl Duroc and Pulawska boars. Fatteners derived from DanAvl Duroc boars were characterized by better meat quality compared to DanAvl Hybrids and their hybrids with Pulawska breed as evidenced by higher pH in 24–96 h post mortem (p.m.), higher sensory evaluation of juiciness, tenderness and flavor as well as lower shear force at lower content of total protein and higher content of intramuscular fat (IMF). However, DanAvl Hybrid fatteners were characterized by poorer meat quality, i.e. higher color lightness (L*) and higher drip loss both from fresh and thawed meat compared to those derived from DanAvl Duroc and Pulawska boars. Meat of fatteners after Pulawska breed was characterized by the highest redness (a*), and that after DanAvl Duroc breed, the lowest yellowness (b*) and saturation (C*).

The Effect of Combined Herbivory by Wild Boar and Small Ruminants on the Regeneration of a Deciduous Oak Forest

The multiple agroforestry land uses of oak forests are of great ecological and economic interest as they contribute to the improvement of animal husbandry, wildlife, and environment. However, herbivory by wildlife and livestock highly affects the structure and the dynamic of forest ecosystems including its regeneration. The aim of this study was to investigate the comparative effect of wild boar and small ruminants herbivory on the regeneration of a deciduous oak forest in northern Greece. Eight sites were selected in an even aged stand of similar canopy cover and forest site quality: four sites with long-time use mainly by wild boar and four sites with long-time grazing by sheep and browsing by goats. A plot of 150 m2 in each of the sites was fenced in order to be protected from herbivory. The plant cover and number of oak seedlings and acorns was measured in both grazed and protected plots for four consecutive years. The plant cover increased in the protected plots independent of the type of animals. The seedling cover decreased about 29% and 9% in sites where small ruminants and wild boars foraged respectively. Similarly, the number and the weight of acorns significantly decreased in the sites grazed by small ruminants mainly during the mast year of the oaks. Forest management has to control the small ruminants grazing in terms of intensity, timing, and duration in order to ensure the sustainability of the ecosystem.

EFFECT OF HYBRID BOARS OF IMPORT SELECTION ON MEAT PERFORMANCE OF PIGS

EFFECT OF HYBRID BOARS OF IMPORT SELECTION ON MEAT PERFORMANCE OF PIGS

THE IMPACT OF SEASON OF BIRTH AND AGE OF BOARS OF POLISH LANDRACE BREED ON BREEDING OPERATION RESULTS

The aim of the study was to assess the impact of season of birth and breeding of boars of Polish Landrace breed on their insemination efficiency. The study material consisted of 35 589 ejaculates collected between 1994-2013 from 330 of Polish Landrace breed boars farmed in Maopolska Biotechnology Centre, the Examination Station of Boars in Czermin. Ejaculates were marked with: volume of ejaculate, without spermatozoid fraction, percentage of progressive spermatozoids, concentration o spermatozoids, the general number of spermatozoids in the ejacu- late, number of insemination doses and value of one ejaculate. The conducted studies demonstrate a significant impact of interaction between the season of birth and the age of boar in the process of development of all the physical parameters of semen in Polish Landrace breed boars. The studies have shown that the highest reproduction potential, demonstrated with the number of insemination doses collected (26.96), was found in the oldest boars born during summer season. The results of studies indicate that quantitative and qualitative parameters of semen of the Polish Landrace breed boars mainly depend on their age. The highest variability affecting the characteristics of ejaculates, resulting from the effect of boars' age, was found for the ejaculate vo- lume of (86.14%), whereas impact of birth season was marked by the percentage of spermatozoids with inferior changes (61.64% of the variability).

Using non-invasive faecal hormone metabolite monitoring to detect reproductive patterns, seasonality and pregnancy in red river hogs (Potamochoerus porcus)

Few studies have been conducted on red river hog ( Potamochoerus porcus ) reproductive biology in zoos. Furthermore, in spite of regular breeding efforts in zoos, reproductive success has been relatively poor for this species, particularly in the North American population. In this study, we used faecal hormone metabolite monitoring to analyse near daily samples from two males and three females over several years to gain insight into their patterns of reproductive hormone secretion. Both a progesterone and a testosterone enzyme immunoassay (EIA) were validated and subsequently used to monitor reproductive patterns, seasonality, ovulatory activity and a successful pregnancy. The findings indicate that female red river hogs are seasonally polyoestrous. Regular cycles were observed from approximately December through August and an annual period of anoestrous was observed from approximately September until December. Average cycle length for all females was 23 days ± 1.19, range 13–30 days. Androgen excretion patterns of the two males did not show clear seasonal patterns. Only one male experienced an increase in androgen levels (141.53 ± 45.55 ng/g) corresponding with the female seasonal oestrous period. There was, however, some evidence of possible androgen suppression between the two males, and a potential ‘boar effect’ on a young female upon first introduction to a male. Ultimately, this information may increase our understanding of this species’ reproductive biology and serve as a baseline for more in-depth follow-up studies to identify specific patterns associated with reproductive success.

Disturbance of the herbaceous layer after invasion of an eutrophic temperate forest by wild boar

Disturbances of the soil and the tree canopy are crucial factors determining the diversity, composition and biomass of the herbaceous layer in forests. This study presents a detailed account of ground vegetation in permanent plots surveyed before and after invasion of wild boar (Sus scrofa) to a temperate deciduous broadleaf forest. Specifically, we aimed to quantify the effect of wild boar rooting on cover, richness and composition of spring ephemerals, summer green herbs and saplings of woody species in relation to tree canopy cover. Rooting frequency in sample plots increased from 0% in 2010 to 61% in 2013. In heavily rooted plots, the mean cover of spring ephemeral geophytes (mainly Anemone nemorosa, A. ranunculoides and Ranunculus ficaria) decreased from 75% to 39% between 2010 and 2013. Species richness of summer green herbs generally increased between 2010 and 2013 and was additionally positively affected by heavy rooting and low canopy cover. Rooting also caused heterogenization of the herbaceous layer and amplified ongoing compositional changes induced by changing light conditions. Frequency and richness of spring ephemeral and woody species remained unchanged. We conclude that overall species richness of the herbaceous layer may increase in the short‐term as a result of increased plant recruitment and seed dispersal. However, wild boar rooting can greatly reduce the ground cover of spring ephemerals in eutrophic broadleaf forests, thereby threatening their important ecological function. To avoid long‐term losses of characteristic spring flora elements, local population control of wild boar is necessary to reduce abundance and frequency of soil rooting.

Negative effect of the wild boar (Sus scrofa) on the population size of the wood mouse (Apodemus sylvaticus) in forest habitats of Sardinia

AbstractThe various activities of the wild boar (

Boar and season effects on some parameters of semen fertilizing potential

In order to determine the more accurate fertile potential of sperm, it seems that the conventional parameters of boar semen quality (the ejaculate volume, sperm concentra?tion, progressive motility, percentage of live sperm and of those with intact acrosomal mor?phology) are insufficient. Since recently, there have been numerous studies proving that protein concentration in sperm plasma has high positive correlation with boar fertile po?tential. The research objective was to determine the effect of boars as well as the season on the variation of protein content in the sperm plasma. For the research there were used spermal fractions of 2 boars with high (V-boar) and 2 boars with low (N-boar) protein con?tent in spermal plasma. The ejaculates of boars were taken once a week, for a month, during one year (4 ? 12 = 48 ejaculates per boar). For protein analysis in the spermal plas?ma, the samples were prepared by centrifugation. The ejaculate volume, protein concen?tration and progressive motility varied considerably (p &lt; 0.05 or p &lt; 0.01) among the boars as well as in one and the same boar. The variations of the same parameters were deter?mined also during both warm and cold season. On the other hand, protein concentration was rather constant, and in V-boars (ranged from 4 to 4.5%) while in N-boars (ranged from 2.3 to 2.6%). The season did not significantly affect (p &gt; 0.01) protein content in sperm plasma (V-boars: 4 to 4.5% in warm and cold season; N-boars: 2.3 do 2.6% in warm and 2.3 to 2.5% in cold season). The obtained results showed that measurement of protein con?tent in boar sperm plasma could be a useful method for their ranking, based on fertile po?tential of fresh semen.

Boar Differences In Artificial Insemination Outcomes: Can They Be Minimized?

In Western countries, where pig breeding and production are intensive, there is a documented variability in fertility between farms with boar-related parameters only accounting to 6% of this total variation of invivo fertility. Such low boar effect could be a result of the rigorous control of sires and ejaculates yielding AI-doses exerted by the highly specialized AI-centres that monopolize the market. However, some subfertile boars pass through these rigorous controls and consequently reach the AI-programmes. Here, we discuss why testing young boars for chromosomal defects, sperm nuclear chromatin integrity and invitro fertilizing ability can be discriminative and economically sound for removing these less fertile boars. Alongside, we discuss why boars differ in the ability of their sperm to tolerate cryopreservation or sex sorting.