Season of Birth and Cardiovascular Mortality in Atrial Fibrillation: A Population-Based Cohort Study

Background: The fetal origins hypothesis have associated early life exposures with the development of adverse health outcomes in adulthood. Season of birth has been shown to be associated with overall and cardiovascular mortality. Methods: We performed a retrospective database study to explore the association between season of birth and mortality in patients with atrial fibrillation. Results: A total of 8962 patients with AF were identified in the database with 1253 deaths recorded. AF patients born in spring and summer had a higher mortality rate when compared to those born in autumn and winter (hazard ratio (HR) 1.13, 95% confidence interval (CI) 1.01–1.26, p = 0.03). This effect was consistent in the male subgroup (HR 1.25, 95% CI 1.03–1.51, p = 0.02 for males born in spring; HR 1.24, 95% CI 1.03–1.51, p = 0.03 for males born in summer when compared to winter as the reference) but not in females (HR 1.02, 95% CI 0.79–1.31, p = 0.88 for females born in spring; HR 1.11, 95% CI 0.87–1.42, p = 0.39 for females born in summer when compared to winter as the reference). Results persisted after adjustment for baseline characteristics and clinical risk profile. A similar pattern was observed with cardiovascular mortality. Conclusion: Birth in spring or summer is associated with a higher risk of cardiovascular mortality in male AF patients, but not in females. This could be related to the underlying differences in rates of major adverse clinical events between genders. Further studies should aim at clarifying the mechanisms behind this association, which may help us understand the higher level of risk in female patients with AF.

The effect of birth month and seasons on athlete aggression

In this study, there were 3,335 football players from four continents from around the world formed a study universe in which the causes of athlete aggression. Also, the factors affecting athlete aggression were investigated with different variables. It has been observed that the levels of aggression of footballers are different according to the positions they play. As the number of matches that players participate in increases, aggression levels increase among the important results. A correlation was found between the ages of the footballers and their levels of aggression, but it was concluded that athletes born in December were more aggressive. Those born in January and those born in winter have shown minimal levels of aggression compared to other footballers. It has been interpreted as having higher levels of aggression, with football players born in December and winter receiving more penalties than other participants. In the continents where football players were born, the highest number of athlete aggression was observed in the participating football players from the continent of Europe, while the aggression of athletes born in the continent of Africa and Asia was found to be lower. Taking into account the data obtained from the research, it was concluded that the athlete's position, age, month, and season of birth and continent of birth are factors affecting athlete aggression.

The effect of individual variation on litter weight in Boer and Jawarandu goat crossbreed

This study aims to determine the effect of individual variations on litter weight in Boer and Jawarandu goat crossbreed in CV. Kambing Burja (farm), East Java. Records from 2012 to 2015 consisted of breed of does, date of birth, litter size and birth weight of kids; along with individual identity, season and year of birth were obtained. There were 107 Boer, 687 Jawarandu, and 495 Boerja does with a total of 3804 kids in the records. Data analysis was conducted using Analysis of Variance (ANOVA) incorporating the factors of season of birth (rainy and dry season) and doe’s breed (Boer, Jawarandu, and Boerja F1). Mixed model analysis using Restricted Maximum Likelihood (REML) method was used to estimate the individual variations. The results showed that both doe’s breed and season of birth had a significant effect (p<0.05) on litter weight; while the individual variations contributed 36.28% to the total variance. We concluded that the individual variation of litter weight was considerably high which reflects high genetic diversity within each breed. Hence, selection to improve the reproductive performance of these goats is highly possible.

Growth Performance of Purgi Goats under Field Conditions in Kargil District (Ladakh)

Background: Purgi goats are native to Ladakh. They are used for fibre production and are known for the quality chevon. A study was, therefore, undertaken to study the effect of non-genetic factors on growth traits of Purgi Goats in its breeding tract. Methods: Flocks of 80 farmers from 8 villages of district Kargil were monitored to collect the data pertaining to growth traits during 2017 and 2018. The data so collected were suitably classified to study the major fixed effects like birth year, kid, parity of dam, season of birth and type of birth. Result: The averages were1.21±0.02, 3.62±0.02, 5.82±0.02, 8.73±0.03, 10.71±0.04 and 13.49±0.09 for BW, WW, 6MW, 9MW, 12MW and 18MW, respectively. The coefficients of variations of all the traits were low. Highest variability of 13.49 was observed for 18MW. The values of least squares means (LSM’s) of 0.96±0.05, 3.74±0.03, 5.80±0.05, 8.74±0.06, 10.87±0.08 and 13.91±0.19 for birthweight (BW), weaning weight (WW), six months body weight (6MW), nine months weight (9MW), yearling body weight (12MW) and eighteen months (18MW) weight were observed in the present study. The effects of sex of kids, season of birth and year of birth were significant (p less than 0.05) on all traits under study, whereas effect of birth-type was significant (p less than 0.05) on BW and WW and effect of parity was non-significant on all traits under study. All the traits BW, WW and 6MW were positively correlated among themselves. The correlations ranged from low (between BW and WW ) to high (WW with 9MW and 12MW).

Effect of Raising Dairy Heifers on Their Performance and Reproduction after 12 Months

The objective of this study was to test the hypotheses that a heifer’s growth, health, and reproduction after 12 months are impacted by rearing (feeding/housing) before weaning, their season of birth, and the father’s lineage. Fifty-one Holstein heifers, born during January–March (SB1), April–June (SB2), July–September (SB3), and October–December (SB4) and originating from four fathers, were assigned to one of the three rearing treatments: restricted suckling (RS), calf in a pen with the mother until the 21st day, sucking three times daily, then group pen (6 kg milk) to weaning; unrestricted suckling (US), calf in a pen with foster cows (6 kg milk) to weaning; and conventional rearing (CR), calf in a hutch until the 56th day, then group pen to weaning (milk replacer 6 kg). After weaning on the 84th day, heifers were kept in groups with the same ration. The growth of the live body weight (LBW), health, and reproduction were recorded. The LBW had a tendency to increase from the 360th to the 570th days in the US, and the reduced growth of the LBW was shown in the CR. Heifers of SB2 had the highest LBW at 570 days of age. The ages of the first insemination service and the conception varied significantly among the rearing groups. The results indicate that a heifer rearing method may have a significant impact on their later growth and fertility.

The Effect of Season of Birth On The Morphometrics of Newborn Belgian Blue Calves

Breed type and environmental factors such as breeding season may have a significant impact on neonatal weight loss calf size. We followed a total of 236 elective cesarean sections in Belgian Blue (BB) cattle, in which neonatal calves were morphometrically measured (in cm) in the first 72 hours after delivery of the child using a strictly standardized protocol. The influence of the season of birth on each calf measurement was analyzed using a mixed linear regression models, including farm of origin as a random effect. Calves born in spring had a longer diagonal length (P = 0.05) (69.7 ± 1.24) than those born in autumn (66.9 ± 1.16). The tibial length of calves born in spring (35.8 ± 0.48) was longer (P> 0.02) than those born in autumn (33.1 ± 0.57) or summer (34.1 ± 0.49). Calves born in autumn have a shorter head diameter (P> 0.02) (12.9 ± 0.23) than those born in summer (12.6 ± 0.29) or winter (13.5 ± 0.22). For all other parameters, no differences were found (P> 0.08). Based on the results of this study, it can be concluded that the birth season influences the morphometrics of neonatal BB calves, with a tendency for spring to be associated with the largest body size. The latter is important to know to avoid dystocia when BB cattle are crossed with other breeds.

Semen Production and Semen Quality of Mehsana Buffalo Breed Under Semiarid Climatic Conditions of Organized Semen Station in India

Semen production data comprising of 55071 ejaculates of 144 bulls from Mehsana buffalo breed was analysed. The traits under study were semen volume, sperm concentration, initial sperm motility, post-thaw sperm motility and number of semen doses per ejaculate. The objective of the present study was to assess the effect of various factors affecting semen production traits and measure the semen production potential of Mehsana buffalo bulls. Data collected of semen production traits were analysed using linear mixed model, including a random effect of bull along with fixed effect of various non-genetic factors like farm, ejaculate number, season of birth, period of birth, season of semen collection and period of semen collection. First ejaculation had higher semen volume and sperm concentration resulted in to higher number of semen doses but semen quality was better in second ejaculation. Season of birth of the bull was affecting semen quality traits. As the period of birth advances semen volume increases whereas sperm concentration decreases which reflected in persistent production of number of semen doses per ejaculate. Monsoon and summer were favorable seasons for semen collection because of higher sperm concentration which resulted in to higher semen doses per ejaculate. Additionally, Monsoon collected semen had highest volume. Hence, monsoon followed by summer season would be the favorable season for semen collection. Period of semen collection affecting all the semen production traits under study but it did not have specific trend which means managemental and environmental changes over the period have sizable influence on the traits. Results of the study will help to plan future managemental practices and breeding strategies to improve semen production traits.

The effect of season of birth on brain epigenome-wide DNA methylation of older adults

Perinatal light exposure predisposes towards health and behaviour in adulthood. Season of birth is associated with psychiatric, allergic, cardiovascular and metabolic problems. It has been proposed that early-life environmental light disrupts the development of biological rhythms which, in turn, influence later-life health. However, the mechanisms linking perinatal seasonal light to later-life biological rhythm and health in humans are unknown. In this study, we investigated the association between season of birth and epigenome-wide DNA methylation of two postmortem human brain regions (16 hypothalamus, 14 temporal cortex). We did not find statistically significant differences at the whole epigenome level, either because we lacked statistical power or that no association exists. However, when we examined 24 CpG sites that had the highest significance or differential methylation, we identified regions which may be associated with circadian rhythm entrainment, cholinergic neurotransmission and neural development. Amongst methylation of the core clock genes, we identified that hypothalamus Neuronal PAS Domain Protein 2 (NPAS2) gene has hypermethylated regions in long photoperiod-born individuals. In addition, we found nominal associations between season of birth and genes linked to chronotype and narcolepsy. Season of birth-related brain DNA methylation profile was different than a previously reported blood methylation profile, suggesting a tissue-specific mechanism of perinatal light programming. Overall, we are the first to analyse the relationship between season of birth and human brain DNA methylation. Further studies with larger sample sizes are required to confirm an imprinting effect of perinatal light on the circadian clock.