Sow Fertility Research Articles

174 Effects of Nursing a Large Litter and Ovarian Response to Gonadotropins at Weaning on Subsequent Fertility in First Parity Sows

Abstract Post-weaning fertility failures occur more often in parity 1 (P1) sows due to increased metabolic demands for lactation and inability to meet energy requirements for maintenance, growth, and reproduction. We hypothesized that body condition loss occurs more frequently in P1 sows nursing a large litter, resulting in impairment of ovarian follicle development during lactation and post-weaning. At 24 h post-farrowing, P1 sows (n = 123) were assigned to treatment (TRT) based on body weight and the number of functional teats to receive High Number (HN, 15 to 16) or Low Number (LN, 12) of nursing pigs. At weaning, sows in each TRT were assigned to receive PG600 or None (Control). During lactation, sow body measures were obtained and ovarian follicles were assessed in mid-lactation and post-weaning. Lactation data were analyzed for the effects of TRT, and fertility data after weaning were assessed for TRT x PG600. There were no interactions of TRT x PG600. During lactation, 22.2% of HN sows lost ≥4 pigs and were removed from analysis. The HN sows lost more (P < 0.05) body weight (-6.2 kg), backfat (-1.0 mm), body condition score (-0.4), and nursing piglets (-0.4) than LN sows. However, HN sows weaned more pigs (14.0) than LN sows (11.0). There was no effect of TRT on wean to estrus interval (4.2 d), but was 0.5 d shorter for PG600 (P = 0.004). There were no effects of TRT or PG600 on estrus within 6 d after weaning (85.6%), but PG600 induced smaller (P = 0.002) follicles at estrus (6.7 mm) than Control (7.3 mm). In the subsequent parity, there were no effects of TRT or PG600 on farrowing rate (93.9%) and total born (13.2). Overall, HN sows lost more piglets and body condition, although they weaned more pigs, but had no effects on reproductive performance.

Influence of climatic factors on the reproductive ability of sows

Taking into account the low level of inheritance of reproductive qualities, it is important to search other factors that may affect the productivity of sows. Therefore, the aim of the work was to study the influence of climatic factors - in this case, the average annual air temperature and humidity on the level of phenotypic manifestation of quantitative traits. In the experiment it was involved a livestock of pigs of the Large White breed of the breeding farm "Ukraine" of Poltava region (factory type "Bahachanskyi"). The research methodology was based on the use of regression and analysis of variance. The estimation of ecological and genetic parameters of plasticity and stability was determined by the method of Eberhart S. J. and Russel W. J. (1966) in the modification of Pakudin V.Z. and Lopatina L.M. (1984). Animals were characterized both by absolute indexes of the productivity and by the selection index (Berezovsky M.D. and others, 2002), and all calculations were performed according to MS Excel 2010. The initial data were formed in a matrix of the type "family-line". When comparing the plasticity of families, genotypes with a coefficient ri> 1.0 were referred to as highly plastic, when1>ri≥0 - relatively plastic. A family in which the plasticity is equal to one and the deviation is minimal is considered as stable. When studying the strength of the interaction influence of climatic factors (temperature and the amount of precipitation per month) on the indexes of reproductive qualities of sows,it has been determined a significant strength of the interaction influence of climatic factors on the fertility of sows (10.62 %). In the study of average indexes of fertility, it was found out the fact that the largest difference in this feature between 2019 and 2020 was recorded in May: fertility in May 2019 was by 1.7 heads higher than in the same period in 2020. The indexes of plasticity (r) and stability (S2) were studied in the context of families. It was determined that the fertility of the sow families are differed by the highest plasticity, and the most stable were sows on the basis of the number of weaned piglets. The greatest reaction in terms of fertility was shown by sows of the families Volshebnytsia and Snizhynka, and the most stable (adapted) were animals of the families Ch. Ptychka and Geran. According to research, a significant effect of temperature and humidity on the fertility of sows of the factory type "Bagachansky", and high values of plasticity of families on this index indicate about an insufficient adaptation of these animals and indicate the feasibility of developing technological measures to mitigate environmental factors. Key words: sow, breed, family, line, factory type, reproductive qualities, selection, adaptation, ecological plasticity, index.

Semen Viability Properties of Sexually Stimulated Boars on the Fertilization Capacity of Artificially Inseminated Large White Sows

Background: This study aimed to investigate the influences of sexual preparation on the effects of boars’ semen viability on the fertilization capacity of artificially inseminated sows. After all, boar sires more pigs than farrowed by a sow which the boar has been mated to improve reproductive parameters in response to AI. Methods: The semen viability of boars were studied during various sexual stimulations and analyzed during the study period. Sperm rich fractions were collected and separated at every level of sexual stimulation during the morning (08:30) and the afternoon (14:30) hours, respectively. Artificial insemination was performed following three levels of sexual preparations of boars (0 minutes of sexual restraint (MSR), 5 MSR and 10 MSR) before semen collection. Receptive sows were inseminated and evaluated for fertility traits using non-return rate, farrowing rate and litter size. Result: The non-return rate was recorded as a percentage of sows conceived after insemination over the total number of sows inseminated. The farrowing rate was recorded as a percentage of sows that farrows over the number of sows conceived and litter size as several live piglets per sow. Sexual desire was influenced by sexual preparations and significantly influenced the fertility of the artificially inseminated sows. This study is of practical significance to the animal breeder mainly because boars have greater influence than sows on the average litter size and live piglets. The study concludes that the use of at least 5 to 10 minutes of sexual restraint during the afternoon periods prior to semen collection and artificial insemination is found to be a practical method for optimizing sperm viability and fertility of sows in the intensive system.

The Suinfort® Semen Supplement Counters Seasonal Infertility in Iberian Sows.

Simple SummaryEfficient pork production relies on a predictable supply of market pigs. Seasonal infertility caused by heat stress decreases fertility in sows during the summer months, impacting breeding targets and decreasing the efficiency of pork production. The present study examined the effect of a seminal additive containing caffeine, oxytocin, and lecirelin on the fertility and prolificacy of Iberian sows during two consecutive years. The results confirmed that inclusion of the additive in semen prior to AI decreased the seasonality effect, increasing the percentage of pregnant Iberian sows throughout the year.Suinfort®, a commercial semen supplement demonstrated to increase fertility and litter size in commercial sows, was tested to improve reproductive performance in Iberian sows. A total of 1430 Iberian sows were artificially inseminated (AI) with semen from Duroc boars and assigned by parity to receive the seminal additive Suinfort® containing 2 IU oxytocin, 5 µg lecirelin, and 2 mM caffeine (SF; n = 1713 AI), or to serve as non-supplemented controls (CON; n = 2625 AI). CON showed a lower fertility comparing to winter for spring (p = 0.001) and summer (p < 0.001); summer was lower than autumn (p = 0.012). SF removed this seasonal effect (p > 0.05). Fertility was significantly higher for SF sows during summer (p = 0.025) and autumn (p = 0.004). Total born, live-born, stillborn, and mummified piglets did not differ between CON and SF but were impacted by the season, with total and live-born decreasing in summer compared with autumn (p < 0.001) and winter (p = 0.005). In conclusion, seminal supplementation with Suinfort® improved the fertility of Iberian sows during periods of seasonal infertility.

Quality and fertility of extended boar semen after prolonged transport

The aim of this study was to analyse semen quality parameters of fresh-extended porcine semen imported from Denmark through prolonged importing regulations and transport and to analyse fertility performance in sows inseminated four days post semen collection. Semen was analysed immediately upon the arrival (4 days post collection) using computer-assisted sperm analyses (CASA), cytomorphology and flow cytometry, and sows were inseminated later the same day. The mean sperm concentration was 1718.09 ± 100.11 × 106 , with average of 1193.40 ± 90.58 × 106 motile cells (69%) and 756.04 ± 70.57 × 106 progressive motile spermatozoa (43.58%) in a dose, which was almost twice lower in value than producer certified-declared number of 2 billion of motile cells. Acrosome and sperm membrane integrity test indicated high percentage of total damaged acrosome. Mean values of semen samples analysed by sperm chromatin structure assay (SCSA) showed relatively high degree of chromatin damage. Membrane permeability test showed high percentage of sperm with damaged membrane. Prolonged transport negatively affected the sperm quality in terms of both motility and chromatin structure stability. Fertility of sows was affected by semen quality in terms of concentration and sperm motility parameters, as well as ratio of live sperm cells population with damaged acrosome.

MiR-2337 induces TGF-\u03b21 production in granulosa cells by acting as an endogenous small activating RNA

Transforming growth factor-β1 (TGF-β1) is essential for ovarian function and female fertility in mammals. Herein, we identified three completely linked variants, including two known variants referred to as c.1583A > G and c.1587A > G and the novel variant c.2074A > C in the porcine TGF-β1 3′-UTR. An important role of these variants in Yorkshire sow fertility was revealed. Variants c.1583A > G and c.1587A > G were located at the miRNA response element (MRE) of miR-2337 and affected miR-2337 regulation of TGF-β1 3′-UTR activity. Interestingly, miR-2337 induces, not reduces the transcription and production of TGF-β1 in granulosa cells (GCs). Mechanistically, miR-2337 enhances TGF-β1 promoter activity via the MRE motif in the core promoter region and alters histone modifications, including H3K4me2, H3K4me3, H3K9me2, and H3K9ac. In addition, miR-2337 controls TGF-β1-mediated activity of the TGF-β signaling pathway and GC apoptosis. Taken together, our findings identify miR-2337 as an endogenous small activating RNA (saRNA) of TGF-β1 in GCs, while miR-2337 is identified as a small activator of the TGF-β signaling pathway which is expected to be a new target for rescuing GC apoptosis and treating low fertility.

Influence of heat stress on the quality of sperm production of boars-producers of different breeds and its fertilizing ability

The primary purpose of this work is to study the heat stress on the quality of sperm production in boars of different breeds (Large White, Landrace, Duroc, Maxgro). The authors found that heat stress affects the activity of pigs. The desire to reduce heat production leads to sedentary, passive animals, accompanied by decreased appetite, shortness of breath and inhibition of sexual reflexes in individuals. Against this background, the disturbances arising in the body, reinforced by a local increase in scrotal temperature, harm semen quality. The authors observed a tendency for decreased ejaculate volume and a decrease (statistically significant in most breeds) in the sperm concentration in the ejaculate by 11.47-34.96%. But at the same time, the organoleptic values (colour, consistency, smell) did not change. Heat stress hurts the fertility of pigs, reducing the probability of successful embryo implantation. The fertility of sow inseminated with semen from boars during heat stress decreased by 10.3-23.7%. And also, the fertility of the sow did not reach pre-stress levels until the end of the observation. Based on the study results, the authors found that, depending on the breed, pigs can tolerate heat stress in a more severe or milder form. The species Large White and Maxgro are less sensitive to increased ambient temperature (they had fewer changes in general condition, semen and fertility) than Duroc and Landrace pigs.

Photo Stimulation of Seminal Doses with Red LED Light from Duroc Boars and Resultant Fertility in Iberian Sows

Simple SummaryThe main objective of breeding Iberian pigs is the production of high-quality dry cured meat products. As this breed shows a reduced litter size in comparison to the commercial breeds, some previous studies have reported the use of photostimulation of seminal doses as a method for improving the farrowing rate and litter size. The aim of this study was to explore whether the application of a photostimulation procedure to Duroc seminal doses has any beneficial effect on fertility and litter size. Semen samples were obtained from 38 fertile Duroc boars and the fertility study was conducted on two commercial farms using multiparous Iberian sows (farm A, n = 824; farm B, n = 2131), that were randomly assigned to LED (L) or control (C) groups. Post-cervical insemination took place 0 and 24 h after the diagnosis of estrus, with seminal doses from the same ejaculate and same treatment. The photostimulation of the seminal doses had no effect on the reproductive performance (farrowing rate: 91.72% C vs. 90.09% L, litter size: 8.71 ± 0.06 piglets C vs. 8.70 ± 0.05 L, p > 0.05).In pigs, it has been reported that increased farrowing rates and litter size have been induced by photostimulating the seminal doses for artificial insemination with red LED light. As the reproductive characteristics, production system, and outcome parameters of Iberian breed pigs are different from other commercial breeds, the aim of this study was to evaluate the possible effect of illuminating seminal doses from Duroc boars with red LED light and the fertility outcomes of Iberian females. Semen samples were obtained from 38 fertile Duroc boars. Photostimulation of the artificial insemination (AI) seminal doses was carried out by illuminating the samples with a red LED for 10 min, followed by 10 min of darkness, and finally 10 additional minutes of red light. The fertility study was conducted on two commercial farms using multiparous Iberian sows (farm A, n = 824; farm B, n = 2131), that were randomly assigned to LED (L) or control (C) groups. No differences were found between L and C groups in both farms (p > 0.05) for parity, pregnancy rate, duration of pregnancy, farrowing rate, and litter size (total, alive, and stillborn piglets). Farrowing rates in farm A were 88.8% (n = 383) for control and 89.6% (n = 441, p = 0.67) for the LED group. In farm B, farrowing rates were C:90.5% (n = 1030) and L: 90.1% (n = 1101, p = 0.48). In farm A, total born piglets were 8.69 ± 0.11 for C and 8.71 ± 0.11 for L (p = 0.87). In farm B, the results were 8.72 ± 0.7 for C and 8.70 ± 0.06 (p = 0.82) for L. Under the production conditions for the Iberian breed, the photostimulation with red LED light using Duroc pig seminal doses was not effective in improving the fertility of Iberian sows.

REPRODUCING QUALITIES OF SOWS OF DIFFERENT FAMILIES OF LARGE WHITE AND POLTAVA MEAT BREEDS IN THE TRIBAL HERDS OF PIGS OF KHMELNYCHINA

Goal. To assess the reproductive ability of inspected sows of different families of large white and Poltava meat breeds in breeding herds of Khmelnytsky region on the main selection signs using the evaluation indices of reproductive qualities. Methods. Comparison, zootechnical and biometric analyzes. Results. The reproductive qualities of sows of different families in breeding herds of pigs of large white and Poltava meat breeds of farms of Khmelnytsky region were evaluated. Among the families of large white breed, the best indicators for assessing the reproductive capacity of inspected sows were found in the family of the Sorceress, in which the main feature – fertility by modal class of distribution was 10.8 heads piglets per 1 farrowing, which is 2.8% more than the Taiga family of the same class. According to the modal class M+, the fertility of the Sorceress family (12.0 piglets per farrowing) was 0.3 heads higher than that of the females of this class of the Taiga family (11.7 heads per farrowing). The modal class М¯ of the firstborn family of the Sorceress was the best with a fertility of 9.7 heads, which is 3.2% higher than the Taiga family. Indicators of the number of piglets at weaning at the age of 30 days, the weight of the nest at weaning, the live weight of 1 head of piglets and preservation of offspring (9.5 heads; 94.1 kg; 9.9 kg; 87.9%), by class (М°), the Sorceress family was 3.2 heads bigger; 7.4 kg; 2.0 kg and 0.5% compared to the Taiga family. As a result of ranking sows by evaluation indices of reproductive qualities, I (evaluation index by a limited number of traits) and P (complex evaluation index) had an advantage by the most prolific sows of the Sorceress family of class M+, in which these indices were 43.0 and 96.1 points. In the process of research of reproductive ability of sows of Poltava meat breed of different families it was established that on the basis of fertility the Rosinka family is the best, whose fertility by distribution by class (М°) was 10.7 heads. piglets per 1 farrowing. It exceeds the average value for 5 families: 0.4 heads of Dorza and Vorskla families, 0.6 goals. Bystro's family and 1 goal. the Palm family. According to the modal class M+, the Rosinka family (11.8 piglets per 1 farrowing) has 0.3 heads more fertility than the Dorza and Vorskla families, 0.6 goals higher. and 0.1 heads than the Bistra and Palma families. The lowest fertility of sows in the class (М°) was recorded in the Dorza family (8.9 heads of piglets per farrowing). It should be noted that the Dorza family and the smallest Palma family in the M+ class have the best nest weight at weaning at the age of 45 days (138.7 and 144.2 kg), which is 18.6 more than in the М° class. and 20.7 kg. According to the indicators of the number of piglets at weaning and live weight of 1 head, the Palma's family of class M+ (10.6 heads and 13.6 kg) is distinguished. The best preservation of the offspring in the Palma's family of class M¯ = 94.7%. As a result of ranking sows of different families of Poltava meat breed according to the estimated indices of reproductive qualities, it was noted that the highest number of points in the modal class (М°) was obtained by the family Rosinka I = 40.8 and P = 94.8, which is more than the average for all families by 2.1 and 3.6 points. According to the evaluation indices (I) and (P), the best were sows of the Rosinka family of class M+, in which these indices corresponded to the values of 42.7 and 99.4 points.&#x0D; Conclusions. Among different families, the best results of assessing the reproductive capacity of sows on the main selection traits and evaluation indices were found in the families of the Sorceress of the Great White breed and the family of Rosinka of the Poltava meat breed, which should continue to be used for breeding in breeding herds of pigs. An important factor in increasing the productivity of sows, of course, should be the correct selection of the level of reproductive breeding traits and a significant increase in feeding and housing conditions.

Age dynamics of reproductive qualities of sows depending on the duration of the suckling period

The article studied the influence of sows' age on their reproductive qualities at the traditional - 28 days and shortened - 21 days duration of the suckling period. It was found that the total number of piglets born increased from the second reproductive cycle to the sixth inclusive. With the traditional duration of the suckling period, the most significant growth was observed during the third, fourth and fifth farrowing (8.0-8.6%), while with a reduced duration of the suckling period, it was significantly lower (3.8-4.9%). and lasted from the third to the fifth reproductive cycle. As sows' reproductive age increased, their fertility increased. Its highest growth in both terms of weaning of piglets was on the third farrowing and then gradually decreased. Sows with a reduced suckling period had a lower increase in fertility throughout reproductive life. The nest weight of piglets at birth increased until the third farrowing and then gradually decreased. With the traditional duration of the suckling period, the intensity of the increase in the nest weight of piglets born at the age of sows is higher compared to analogues in which the lactation period was reduced. Preservation of piglets in sows' nests deteriorated with increasing reproductive age. It worsened less intensely in sows with a reduced suckling period. The number of weaned piglets depended to a greater extent on the age of the sows and to a lesser extent on the length of the suckling period. From the third farrowing, it constantly decreases with increasing age of the sow, regardless of the length of the suckling period. The average weight of one piglet increases with the age of sows from the third farrowing, and its growth is more intense with a reduced duration of lactation. The increase in the weight of the nest of piglets at weaning is most significant for 3-5 farrowings, after which there was a decrease in this indicator for both periods of weaning piglets. A comprehensive assessment of the reproductive quality of sows using indices confirms the increase in sow productivity during the second - fourth reproductive cycle with a gradual decrease during the fifth to sixth farrowing, both in the traditional and reduced duration of the suckling period. It is proved that the sow age factor determines the probable influence on the number of piglets at weaning (9.43 %), their safety (5.56 %), the weight of the nest of piglets at weaning (1.87 %) and fertility (1.65 % ). While the suckling period factor affected the nest weight of piglets at weaning with a force of 28.49 %, the number of piglets at weaning with a force of 0.62 %, the safety of piglets before weaning at 0.19 % and did not affect the fertility of sows. Key words: sow, reproductive cycle, duration of lactation, fertility, safety, piglet.

Timing and temperature thresholds of heat stress effects on fertility performance of different parity sows in Spanish herds.

High temperature is an environmental factor that impairs sow fertility. In this study, we identified the critical weeks for heat stress effects on aspects of fertility performance, namely weaning-to-first-service interval (WSI) and farrowing rate (FR). We also examined the threshold temperatures above which the fertility performance deteriorated and whether there were any differences between parities regarding heat stress effects or thresholds. Performance data of sows in 142 herds from 2011 to 2016 were matched to appropriate weekly averaged daily maximum temperatures (Tmax) from weather stations close to the herds. Two types of ratios (i.e., ratio for WSI and odds ratio for FR) were used to identify the critical weeks for heat stress by comparing the respective measures for two sow groups based on Tmax in different weeks around weaning or service events. The ratios for WSI were calculated between groups of sows exposed to Tmax ≥ 27 °C or <27 °C in each week before weaning, with the Tmax cutoff value based on a recent review study. Similarly, the odds ratios for FR for the two groups were calculated in weeks around service. The weeks with the largest differences in the fertility measures between the two Tmax groups (i.e., the highest ratio for WSI and the lowest odds ratio for FR) were considered to be the critical weeks for heat stress. Also, piecewise models with different breakpoints were constructed to identify the threshold Tmax in the critical week. The breakpoint in the best-fit model was considered to be the threshold Tmax. The highest ratios for WSI were obtained at 1 to 3 wk before weaning in parity 1 and 2 or higher sow groups. The threshold Tmax leading to prolonged WSI was 17 °C for parity 1 sows and 25 °C for parity 2 or higher sows. Increasing Tmax by 10 °C above these thresholds increased WSI by 0.65, and 0.33 to 0.35 d, respectively (P < 0.01). For FR, the lowest odds ratios were obtained at 2 to 3 wk before service in parity 0, 1, and 2 or higher sow groups. The threshold Tmax leading to reductions in FR was 20, 21, and 24 to 25 °C for parity 0, 1, and 2 or higher sow groups, respectively. Increasing Tmax by 10 °C above these thresholds decreased FR by 3.0%, 4.3%, and 1.9% to 2.8%, respectively (P < 0.01). These results indicate that the critical weeks for heat stress were 2 to 3 wk before service for FR and 1 to 3 wk before weaning for WSI. The decreases in fertility performance in parity 0 to 1 sows started at temperatures 3 to 8 °C lower than in parity 2 or higher sows.

A Bayesian analysis of boar spermatozoa kinematics and head morphometrics and their relationship with litter size fertility variables.

The semen movement and sperm head size patterns of boar ejaculates were analysed using computer-assisted semen analysis (CASA)-Mot and -Morph systems. The aim of the present study was to compare morphometric and kinematics variables from boars and to determine the relationship with sow fertility variables related to litter size. The females were from maternal crossing schemes such as the continuous 3-generation cross between York (Y), Landrace (L), and Pietrain (P) hybrid sows and Pietrain boars. Semen samples were collected from 11 sexually mature boars from two sire lines. Samples were analysed using the ISAS® v1 system to evaluate eight kinematic variables of sperm velocity, progressiveness and undulations. Four morphometric parameters of sperm head size (length, width, area and perimeter) were analysed. Bayesian analysis revealed relevant differences in four kinematic variables (VSL, LIN, STR and WOB) between sire lines, with a probability of relevance (PR ) of 0.79-0.91, and Pietrain boars were associated with higher progressive motility compared with Duroc x Pietrain boars. Moreover, there were relevant differences in all morphometric variables (PR =0.82-0.85) between sire lines. The dam line Y-L-50 (½ Y×½ L) had higher total born per litter and piglets born alive, and YLP-75 (1 /8 Y×1 /8 L×3 /4 P) was associated with higher values of litter weight at birth (highest posterior density region at 95%=9.92, 16.41kg). There are relevant differences in kinematic variables between the assessed sire lines and the differences in morphometric and litter size variables were also relevant. The York-Landrace hybrid sows had higher total born per litter and piglets born alive, and there were relevant differences when compared with YLP-50 (¼ York×¼ Landrace×½ Pietrain). Differences in kinematic and morphometric variables between sire and dam lines related to fertility need to be further studied.

PSVI-6 Thresholds of Outdoor Temperatures on Fertility Measures of Different Parity Sows in Spanish Herds

Abstract High temperature is one of the environmental factors which impair sow fertility such as weaning-to-first-mating interval (WMI) and farrowing rate especially in parity 1 sows. The objective of this study was to explore thresholds of temperature damaging fertility in different parity sows. Data of sows serviced from 2011 to 2016 in 142 herds were coordinated with daily maximum temperature (Tmax) from 31 weather stations close to the herds. A two-stage approach was used to determine the best fit model. In the first stage, means and their variance-covariance matrix in each degree Celsius were estimated by a mixed model. Then, piecewise models with a different breakpoint were fitted to the estimates by generalized least squares. Medians of WMI in parity 1 and 2 or higher sows were 5 and 4 days, respectively. Farrowing rates in different parity sows were 85.0–88.7%. The thresholds of mean Tmax during lactation leading to a prolonged WMI were 16 and 23–25°C for parity 1 and 2 higher sows, respectively. The 10°C increase in Tmax from the thresholds delayed WMI in parity 1 and 2 or higher sows by 0.62 and 0.46–0.49 days, respectively (P &amp;lt; 0.01). Meanwhile, the thresholds of mean Tmax from 21 to 14 days before service leading to reductions in farrowing rate were 21, 19 and 21–22°C for parity 0, 1 and 2 or higher sows, respectively. As the Tmax increased by 10°C from the thresholds, farrowing rate in parity 0–1 and 2 or higher sows decreased by 2.9 and 2.2–2.6%, respectively (P &amp;lt; 0.01). Lactating sows in parity 1 suffered from heat stress at a relatively low outdoor temperature. This implies that the temperature is warmer in lactating barns than in outdoor. We recommend changing thermostat set at barns in spring from those in winter in order to increase ventilation rates earlier.

Reproductive health indicators of sows using azoxymer bromide

The aim of the research was to study the effect of different regimens of using «Azoxivet» on the duration of pregnancy, labor and restoration of sexual cycling in sows. «Azoxivet» is a synthesized immunomodulator with detoxicant and antioxidant properties. The active substance «Azoxivet» is azoxymer bromide. The research was carried out on sows of the large white breed, live weight of 180-230 kg, which had 1-4 farrowings in anamnesis. 90 sows at 80 days of gestation were divided into 3 groups . Sows of group 1 (G1, n=30) were injected with «Azoxivet» intramuscularly 3 times in interval of 7 days from the 100th day of gestation at a dose of 0.1-0.15 mg/kg (18 mg). Sows of group 2 (G2) were injected with «Azoxivet» twice at 100th days of gestation and on the day of farrowing at the same dose. Sows of group 3 (G3) was control. Clinical observation of sows were conducted during pregnancy, in time of labor and in postpartum periods. In sows, we took into account the pregnancy rate, the course of labor, the restoration of sexual cyclicity after weaning of piglets. The presence of the estrus was detected in once a day in the morning hours with using a teaser boar. Artificial insemination (AI) efficiency was determined on 28th day with ultrasound. Data were analyzed by MIXED of SAS program. The gestation periods in sows in G1, G2 and G3 were 114.50 ± 0.28, 114.86 ± 0.26 and 114.72 ± 0.19 days, respectively. In G3, 3.33% of the sows had a pregnancy pathology caused by an abortion on 105th day . In G1 and G2, no pregnancy pathologies were revealed. The greatest duration of the labor act was recorded in G3 - 234.63 ± 18.71 min, while in G1 and G2 the labor was lasted 27.13 and 34.86 min less. In G1 and G2, labor complications were observed only in 13.64% and 14.28% of females, while in G3 - in 36.84% of sows. After weaning piglets and transferring sows to the section of barren sows, recovery of sexual cyclicity was registered in 81.48% in G3, which is 6.98% and 10.52% less than in G1 and G2. In all groups, the manifestation of estrus was observed for 4-6 days. The average duration from weaning to the manifestation of estrus in animals G1 was 4.60 ± 0.22 days, in G2 - 4.65 ± 0.13 days, in G3 - 4.32 ± 0.10 days. The effectiveness of AI according to the results of an ultrasound carried out on the 28-30th day after insemination was high in all studied groups and amounted to 95.65-100%. Consequently, the using «Azoksivet» has a positive effect on the pregnancy, the course of their labor process and the activation the sexual cyclicity after weaning of piglets, ensures high fertility of sows and increases the duration of the economic using of animals.

Predictive Capacity of Boar Sperm Morphometry and Morphometric Sub-Populations on Reproductive Success after Artificial Insemination.

Simple SummaryThe efficiency of swine production measured as litter size influences the profitability of the pig industry. Furthermore, sow fertility potential depends in part on the boar semen quality and reproductive efficiency. The objective of this study is to compare boar sperm head size and morphometric features of shape to evaluate their relationships with reproductive success after artificial insemination (AI). A morphometric analysis of boar ejaculate reveals morphometrically separate sub-populations. The differences between sub-populations are displayed for sperm head size. In addition, sperm clustering into sub-populations did not have a predictive capacity on litter size variables. Nevertheless, the morphometric variables of the sperm may have a predictive, albeit reduced, capacity regarding litter size variables. The results of this study therefore open up possibilities for future assessments of fertility. The aim of the study was to compare the morphometric features of sperm head size and shape from the Pietrain line and the Duroc × Pietrain boar crossbred terminal lines, and to evaluate their relationship with reproductive success after artificial insemination of sows produced from crossbreeding the York, Landrace and Pietrain breeds. Semen samples were collected from 11 sexually mature boars. Only ejaculates with greater than 70% motility rate and <15% of abnormal sperm were used for artificial inseminations (AI) and included in the study. Samples were analyzed using an ISAS®v1 computer-assisted sperm analysis system for eight morphometric parameters of head shape and size (CASA-Morph). Sub-populations of morphometric ejaculates were characterized using multivariate procedures, such as principal component (PC) analysis and clustering methods (k-means model). Four different ejaculate sub-populations were identified from two PCs that involved the head shape and size of the spermatozoa. The discriminant ability of the different morphometric sperm variables to predict sow litter size was analyzed using a receiver operating characteristics (ROC) curve analysis. Sperm head length, ellipticity, elongation, and regularity showed significant predictive capacity on litter size (0.59, 0.59, 0.60, and 0.56 area under curve (AUC), respectively). The morphometric sperm sub-populations were not related to sow litter size.

Transcriptomic Data Analyses Reveal That Sow Fertility-Related lincRNA NORFA Is Essential for the Normal States and Functions of Granulosa Cells.

NORFA, the first lincRNA associated with sow fertility, has been shown to control granulosa cell (GC) functions and follicular atresia. However, the underlying mechanism is not fully understood. In this study, RNA-seq was performed and we noticed that inhibition of NORFA led to dramatic transcriptomic alterations in porcine GCs. A total of 1,272 differentially expressed transcripts were identified, including 1167 DEmRNAs and 105 DEmiRNAs. Furthermore, protein–protein interaction, gene-pathway function, and TF–miRNA–mRNA regulatory networks were established and yielded four regulatory modules with multiple hub genes, such as AR, ATG5, BAK1, CENPE, NR5A1, NFIX, WNT5B, ssc-miR-27b, and ssc-miR-126. Functional assessment showed that these hub DEGs were mainly enriched in TGF-β, PI3K-Akt, FoxO, Wnt, MAPK, and ubiquitin pathways that are essential for GC states (apoptosis and proliferation) and functions (hormone secretion). In vitro, we also found that knockdown of NORFA in porcine GCs significantly induced cell apoptosis, impaired cell viability, and suppressed 17β-estradiol (E2) synthesis. Notably, four candidate genes for sow reproductive traits (INHBA, NCOA1, TGFβ-1, and TGFBR2) were also identified as potential targets of NORFA. These findings present a panoramic view of the transcriptome in NORFA-reduced GCs, highlighting that NORFA, a candidate lincRNA for sow fertility, is crucial for the normal states and functions of GCs.

Influence of the breeding environment factors on the number of the weaned piglets

Article Details: Received: 2020-10-22 | Accepted: 2020-11-27 | Available online: 2021-01-31 https://doi.org/10.15414/afz.2021.24.mi-prap.131-134 A prerequisite for the successful pig breeding isthe achievement of high reproductive performance, which can be influenced by several environmental factors. Therefore, the aim of our research was to assess the impact of the season, microclimatic indicators and technology of housing of the lactating sows on the number of the weaned piglets in the litter. The experiment was performed on a production farm in Slovakia and a total of 800 litters were evaluated. The results have shown that the season had a statistically significant effect on the number of the weaned piglets ( p <0.01), least in the summer and most of them in the fall. The highest number of the weaned piglets was found at the temperatures from 18 to 22 °C ( p <0.05), temperatures outside the stated range had a negative impact on the number of the weaned piglets. An increase of the relative humidity - above 70% ( p <0.05) and an increase in the flow - above 0,4 m.s -1 ( p <0.05) led to a decrease in the number of the weaned piglets. In the housing with a freemovement of the lactating sows, the number of the weaned piglets was higher than with the restricted movement ( p <0.05). Keywords: microclimate, technology, weaned piglets References Boudný, J. & Spicka, J. (2012). The effect of production efficiency on economic results in pig breeding. Res. Pig Breeding , 6(1), 1-8. Close, W. (1992). Thermoregulation in piglets: Environmental and metabolic consequences. BSAP Occasional Publication ,15, 25-33. https://doi.org/10.1017/S02639674067 English, P. R. & Edwards, S. A. (1996). Management of the nursing sow and her litter. In Dunkin A. C. & Taverner, M. (eds.). Pig Production. World Animal Science (Vol. C10 ). Amsterdam, Netherlands: Elsevier (pp. 113-140). Holmes, C. W. & Mount, L. E. (1967). Heat loss from groups of growing pigs under various conditions of environmental temperature and air movement. J. Anim. Prod. , 9, 435-452. https://doi.org/10.1017/S0003356100042008 Horký, P. (2014). Influence of increased dietary selenium on glutathione peroxidase activity and glutathione concentration in erythrocytes of lactating sows. Ann. Anim. Scie. , 14(4), 869-882. https://doi.org/10.2478/aoas-2014-0056 Matousek, V. et al. (2013). Livestock breeding II. Ceske Budějovice : JU ZF. In Czech. Myer, R. & Bucklin, R. (2018). Influence of hot-humid environment on growth performance and reproduction of swine. AN107: UF/IFAS Extension , 1-6. Nevrkla, P. et al. (2016). analysis of reproductive parameters in sows with regard to their health status. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis . 64, 481-486. https://doi.org/10.11118/actaun201664020481. Novak, P. & Rožňovský, J. (2009). Influence of microclimate on the pig performance. In Current knowledge about the pig breeding: proceedings from the International Scientific Conference 41 held on the occasion of the 90th anniversary of MZLU in Brno . Brno: MZLU (pp. 45-48). In Czech. Prunier, A. et al. (1996). Environmental and seasonal influences on the return-to-oestrus after weaning in primiparous sows. Livestock Production Science , 45, 103-110. https://doi.org/10.1016/0301-6226(96)00007-3 Rodrigues, S. V., Pla, L. M. & Albornoz, V. M. (2012). Modeling tactical planning decisions through a linear optimization model in sow farms. Livest. Sci. , 143(2-3), 162-171. Rolinec, M. (2020). The Effect of coconut oil addition to feed of pigs on rectal microbial diversity and bacterial abundance. Animals (Basel) , 10(10), E1764. https://doi.org/10.3390/ani10101764 Rozkot, M. (2014). Pigs technology and the public. Nas chov , 74(10), 63-66. In Czech. Sallvik, K. & Walberg, K. (1984). The effects of air velocity and temperature on the behaviour and growth of pigs. J. of Agricultural Engineering. Research , 30, 305-312. https://doi.org/10.1016/S0021-8634(84)80031-1 Silva, B. A. N. et al. (2006). Effect of floor cooling on performance of lactating sows during summer. Livest. Sci. , 105, 176-184. https://doi.org/10.1016/j.livsci.2006.06.007 Suriyasomboon, A. et al. (2006). Effect of temperature and humidity on reproductive performance of crossbred sows in Thailand. Theriogenology , 65, 606-628. https://doi.org/10.1016/j.theriogenology.2005.06.005 Vanerhaeghe, C. et al. (2010). Longitudinal field study to assess sow level risk factors associated with stillborn piglets. Anim. Reprod. Sci., 120(1-4), 78-83. https://doi.org/10.1016/j.anireprosci.2010.02.010 Wegner, K. et al. (2014). Climatic effects on sow fertility and piglet survival under influence of a moderate climate. Animal , 8(9), 1526-1533. https://doi.org/10.1017/S1751731114001219.

Artificial insemination in sows using Guelph and two local semen extenders

Sixty two and half-year-old Large White sows and 12 boars of the same breed and age were used to study the comparative effects of conventional (Guelph) and local (coconut water and fresh raphia palm wine) extenders and storage (3 days) on the fertility of artificially inseminated sows. Semen was collected twice a week by gloved-hand method. Semen was either extended or unextended and evaluated on the day of collection (day 0) and during day 3 of storage for percentage sperm motility, acrosome morphology and fertility (Non-return rate, farrowing rate and litter size). Both Guelph and local extenders produced significant effects (P&lt;0.01) on boar semen characteristics and fertility. Fresh semen extended in Guelph entender had the highest percentage sperm motility (86.2%) whereas fresh semen extended with coconut water gave the highest normal apical ridge (NAR) (91%); farrowing rate (88.3%). Litter size (7.1 piglets/litter alive (5.8), with the highest number of non return to service sows. Guelph extended semen ranked second in influencing fertility in sows.

Gilt birth weight, sow birth weight phenotype and sow fertility

Gilt birth weight, sow birth weight phenotype and sow fertility

SMARCA2 is regulated by NORFA-miR-29c, a novel pathway that controls granulosa cell apoptosis and is related to female fertility.

SMARCA2, an evolutionarily conserved catalytic ATPase subunit of SWI/SNF complexes, has been implicated in development and diseases; however, its role in mammalian ovarian function and female fertility is unknown. Here, we identified and characterized the 3'-UTR of the porcine SMARCA2 gene and identified a novel adenylate number variation. Notably, this mutation was significantly associated with sow litter size traits and SMARCA2 levels, due to its influence on the stability of SMARCA2 mRNA in ovarian granulosa cells (GCs). Immunohistochemistry and functional analysis showed that SMARCA2 is involved in the regulation of follicular atresia by inhibiting GC apoptosis. In addition, miR-29c, a pro-apoptotic factor, was identified as a functional miRNA that targets SMARCA2 in GCs and mediates regulation of SMARCA2 expression via the NORFA-SMAD4 axis. Although a potential miR-29c-responsive element was identified within NORFA, negative regulation of miR-29c expression by NORFA was not due to activity as a competing endogenous RNA. In conclusion, our findings demonstrate that SMARCA2 is a candidate gene for sow litter size traits, because it regulates follicular atresia and GC apoptosis. Additionally, we have defined a novel candidate pathway for sow fertility, the NORFA-TGFBR2-SMAD4-miR-29c-SMARCA2 pathway.This article has an associated First Person interview with the first author of the paper.