Coefficients of repeatability for colostrum and milk composition of PLW and PL sows over three consecutive lactations

Animal board invited review: Factors affecting the early growth and development of gilt progeny compared to sow progeny

Progeny born to primiparous sows farrowing their first litter, often called gilt progeny (GP), are typically characterised by their poorer overall production performance than progeny from multiparous sows (sow progeny; SP). Gilt progeny consistently grow slower, are born and weaned lighter, and have higher postweaning illness and mortality rates than SP. Collectively, their poorer performance culminates in a long time to reach market weight and, ultimately, reduced revenue. Due to the high replacement rates of sows, the primiparous sow and her progeny represent a large proportion of the herd resulting in a significant loss for the pig industry. While the reasons for poorer performance are complex and multifaceted, they may largely be attributed to the immature age at which gilts are often mated and the significant impact of this on their metabolism during gestation and lactation. As a result, this can have negative consequences on the piglet itself. To improve GP performance, it is crucial to understand the biological basis for differences between GP and SP. The purpose of this review is to summarise published literature investigating differences in growth performance and health status between GP and SP. It also examines the primiparous sow during gestation and lactation and how the young sow must support her own growth while supporting the metabolic demands of her pregnancy and the growth and development of her litter. Finally, the underlying physiology of GP is discussed in terms of growth and development in utero, the neonatal period, and the early development of the gastrointestinal tract. The present review concludes that there are a number of interplaying factors relating to the anatomy and physiology of the primiparous sow and of GP themselves. The studies presented herein strongly suggest that poor support of piglet growth in utero and reduced colostrum and milk production and consumption are largely responsible for the underperformance of GP. It is therefore recommended that future management strategies focus on supporting the primiparous sow during gestation and lactation, increasing the preweaning growth of GP to improve their ability to cope with the stressors of weaning, selection of reproductive traits such as uterine capacity to improve birth weights and ultimately GP performance, and finally, increase the longevity of sows to reduce the proportion of GP entering the herd.

Dietary Inclusion of 1,3-Butanediol Increases Dam Circulating Ketones and Increases Progeny Birth Weight

Simple Summary

Gilt progeny are born and weaned lighter and have poorer life-time performance than sow progeny. Low birth weights and pre-weaning mortality are highly associated with and are often a result of reduced milk consumption and vigor. Glycogen stores are deposited in utero and are relied on heavily within the first hours of life. Because of rapid depletion of these stores, piglets must consume enough milk immediately post-partum for survival. Similar to glucose, ketone bodies have the ability to readily pass the placenta for the piglet to use in the neonatal period. Supplementing late gestation diets with ketogenic substances as an alternative source of energy can potentially be used by the piglet, reducing the rapid depletion of glycogen stores. This study supplemented late gestation diets of both gilts and sows with the ketogenic substance 1,3-Butanediol and found that birth weights and total litter weights were increased in both gilt and sow progeny. While Butanediol can potentially increase birth weight and growth performance in the post-parturition period, a strong parity effect was still evident throughout the study with sow progeny outperforming gilt progeny

Abstract

1,3-Butanediol (BD) is a ketogenic substance that can improve piglet growth and survival and potentially increase performance in gilt progeny when provided as a dietary supplement during late gestation. Gilts (n = 77; parity 1) and sows (n = 74; parities 2 and 3) were fed either a standard commercial gestation diet or a diet supplemented with 4% BD from day 90 of gestation until farrowing. Dams fed with diets supplemented with BD had higher plasma beta-hydroxybutyrate (p = 0.01) and lower non-esterified fatty acid concentrations (p < 0.001). The percentage of progeny that were light-for-age (<1.1 kg) at birth was decreased by BD (18.2 vs. 13.5%, p < 0.006), particularly in gilts (24.0 vs. 18.3%, p < 0.034). Individual birth weights and litter weights birth weights tended to be increased by the BD diet (p = 0.085 and 0.078; respectively) although these effects were not maintained to weaning. Pre-weaning mortality was greater in gilt than in sow progeny and was not altered by dietary BD. Feeding BD in late gestation can improve birth weight, but further work is needed to see if these effects are carried through subsequent stages of growth, particularly in gilt progeny.

Recurrence patterns and lifetime performance of parity 1 sows in breeding herds with different weaning-to-first-mating intervals

Background

Our objectives were 1) to compare reproductive performance across parities and lifetime performance of parity 1 sows in six weaning-to-first-mating interval groups (WMI 0-3, 4, 5, 6, 7-20 and 21 days or more), 2) to determine the recurrence patterns and repeatability of WMI, and 3) to quantify factors associated with the probability of parity 1 sows having WMI 4 days. Examined data comprised 691,276 parity and 144,052 lifetime records of sows in 155 Spanish herds, served between 2011 and 2016. Mixed-effects models were applied to the data. Variance components analysis determined WMI repeatability.

Results

Proportions of parity 1 sows with WMI 0-3, 4, 5, 6, 7-20 and 21 days or more were 4.1, 30.0, 38.4, 7.9, 12.7 and 6.9%, respectively. Of the parity 1 sows with WMI 0-4 days, 43.3-60.5% had WMI 4 days in later parities, whereas 33.9-48.9% of those with WMI ≥5 days had WMI 5 days; WMI repeatability was 0.11. Parity 1 sows with WMI 4 or 5 days had 0.3-2.1 days shorter WMI in later parities than those with WMI ≥7 days (P <  0.05). Parity 1 sows with WMI 4 or 5 days also had 0.6-2.1 more annualized lifetime piglets born alive than those with WMI ≥7 days (P <  0.05). Notably, parity 1 sows with WMI 4 days had 0.3 more annualized lifetime piglets born alive than those with WMI 5 days (P <  0.05).

Conclusion

The WMI in parity 1 could be a useful predictor for subsequent reproductive performance and lifetime performance of sows.

Primiparous and Multiparous Sows Have Largely Similar Colostrum and Milk Composition Profiles Throughout Lactation

It is important to understand the biological factors influencing the poorer lifetime performance of gilt progeny in comparison to sow progeny and determine whether this may be partially due to differences in lactation performance between primiparous and multiparous sows. It was hypothesized that primiparous sows would have lower levels of immunoglobulin G (IgG) in colostrum and milk compared to multiparous sows, and lower levels of other energetic components. Differences in colostrum and milk composition between ten primiparous and ten multiparous sows (parities 3 and 4) from a commercial herd were examined throughout lactation (day 0, 1, 2, 3, 7, 14, and 21). Overall, there were no (p ≥ 0.05) parity differences in total IgG, fat, protein, lactose, and net energy (NE) concentrations. Primiparous sows had higher lactose levels at day 2 (parity by timepoint interaction; p = 0.036) and lower NE at day 3 (p = 0.091), and multiparous sows had higher lactose levels at days 14 and 21. Results suggest that shortcomings of gilt progeny are unlikely due to insufficient nutrient levels in colostrum and milk, and more likely to reduced colostrum and milk intake and their capacity to digest and absorb each component.