Seasonal variation in sperm characteristics of boars in southern Uruguay

Abstract

-The objective of this study was to evaluate the effects of season, natural photoperiod, and room temperature at the housing facility on boar semen characteristics in Uruguay (34º66'S; 56º29'W). For this purpose, 117 ejaculates, obtained from eight adult males collected through 12 consecutive months, were assessed for sperm viability, DNA integrity, abnormalities (total, primary, and secondary), ejaculate volume, and sperm concentration. Viability, total and primary abnormalities, volume, and sperm concentration were affected by season. Sperm viability, volume, and sperm concentration were affected by natural photoperiod. In general, autumn and the decreasing photoperiod had a negative impact on most of the semen characteristics, except for volume. Housing temperature did not affect semen characteristics. In boars living in temperate climates, semen quality is negatively affected during autumn and is related to photoperiod changes; however, the effects of temperature changes in housingdo not affect these seminal characteristics. In this scenario, seasonal differences in semen quality may have a negative effect on sow fertilization. Consequently, semen quality control especially during autumn is imperative for the best boar selection to be used for insemination purposes. Seasonal differences in semen quality may have a negative effect on sow reproductive performance. This issue will be addressed in a future investigation.

Revisiting summer infertility in the pig: could heat stress-induced sperm DNA damage negatively affect early embryo development?

“…Ejaculates collected during spring-summer had significantly lower volume, sperm concentration and number of spermatozoa with functional mitochondria and intact plasma membrane (Zasiadczyk et al 2015). By contrast, Petrocelli et al (2015) observed photoperiod to be more important than housing temperature in affecting most boar semen characteristics.…”

“…This supports an earlier study by Zasiadczyk et al (2015) in which sperm DNA fragmentation is markedly higher in spring-summer than in autumn-winter in fractionated ejaculates (particularly F 1 and F 2 ) using neutral comet assay. Moreover, results by Petrocelli et al (2015) suggest possible seasonal DNA damage to boar spermatozoa.…”

Intraindividual Variation of Meiotic Recombination Parameters in Pig Spermatocytes: A Preliminary Study

“…Our aim was not to investigate a possible effect of age (a 1-year interval would be too short in that perspective), but rather to check for the occurrence of significant differences between sampling periods in the same individuals (intraindividual variation). The 1-year interval was chosen in order to circumvent a putative seasonal effect [Petrocelli et al, 2015].…”

Landscape genomic approach to detect selection signatures in locally adapted Brazilian swine genetic groups

“…The environmental variables from the Brazilian territory were obtained at the World ClimProject (http://www.worldclim.org/), GTOPO30 (https://lta.cr.usgs.gov/GTOPO30), and Harvest Choice (http://harvestchoice.org/) and 30-s geographical information system (GIS) layer using Qgis v2.6 (QGIS Development Team 2009). Monthly maximum, average and minimum temperature, annual average and median for maximum, average and minimum temperature, seasonal averages and medians for maximum, average and minimum temperature, monthly solar radiation, annual average and median solar radiation, seasonal averages and medians solar radiation, monthly precipitation, annual average and median precipitation seasonal averages and medians precipitation, 19 bioclimatic variables (BIO1-19), elevation, PETannual (annual potential evapotranspiration), and Aridity (ratio of precipitation to PET) were obtained for each sample from this layer (Table S2) performance (De Rensis, Ziecik, & Kirkwood, 2017;Petrocelli, Batista, & Gosálvez, 2015;Prunier, Quesnel, de Bragança, & Kermabon, 1996), pulmonary disease (Eze et al, 2015;Gao, Xiao, Qin, Cao, & Wang, 2016) piglet early survey (Berger et al, 2007;Iida & Koketsu, 2014) in all stages of life (Ross et al, 2015;Wildt, Riegle, & Dukelow, 1975), including intrauterine development (Johnson et al, 2013(Johnson et al, , 2015, we used the environmental variables in an exploratory approach, to identify the influence of each explanatory variable on the allele frequencies.…”