Effects of different levels of feed intake during four short periods of gestation and housing systems on sows and litter performance

Preweaning performance in intrauterine growth-restricted piglets: Characteristics and interventions

Intrauterine growth restriction (IUGR) is frequently observed in pig production, especially when using highly prolific sows. IUGR piglets are born with low body weight and shape indicative of differences in organ growth. Insufficient uteroplacental nutrient transfer to the fetuses is the leading cause of growth restriction in the pig. Supplementing the sow's gestation diet with arginine and/or glutamine improves placenta growth and functionality and consequently is able to reduce IUGR incidence. IUGR piglets are at higher risk of dying preweaning and face higher morbidity than their normal-weight littermates. A high level of surveillance during farrowing and individual nutrient supplementation can reduce the mortality rates. Still, these do not reverse the long-term consequences of IUGR, which are induced by persistent structural deficits in different organs. Dietary interventions peri-weaning can optimize performance but these are less effective in combating the metabolic changes that occurred in IUGR, which affect reproductive performance later in life. IUGR piglets share many similarities with IUGR infants, such as a poorer outcome of males. Using the IUGR piglet as an animal model to further explore the structural and molecular basis of the long-term consequences of IUGR and the potential sex bias could aid in fully understanding the impact of prenatal undernutrition and finding solutions for both species and sexes.

Short- and Long-Term Effects of Birth Weight and Neonatal Care in Pigs

Swine industries worldwide face a loss in profit due to high piglet mortality, particularly as a consequence of the marked increase in prolificity and low birth weight (BW) of piglets. This research studied the effect of BW and individual neonatal care provided to piglets on preweaning mortality, and the long-term effects on growth and carcass and meat characteristics. Litters from seventy-one crossbred sows (PIC 34) were included in the trial. Half of each litter did not receive any further management, and the remaining half received the pre-established management protocol of early assistance of neonatal care (NC). Along lactation, the low-BW piglets (weight equal to or less than 1.1 kg) showed a threefold higher mortality rate than piglets of higher weights (32 vs. 10%; p = 0.001), with mortality particularly concentrated within the first week after birth. No effect of NC treatment was observed on mortality ratio caused by crushing, but a significant effect was observed in low-BW piglets who died of starvation (p < 0.01). The effect of NC on growth is dependent on BW, and heavier piglets at birth benefit from NC treatment to a higher extent than low-BW piglets. Low-BW piglets showed a higher fatness (p = 0.003), lower lean cut yield (p = 0.002) in carcasses, and higher intramuscular fat (IMF) content (2.29% vs. 1.91%; p = 0.01) in meat. NC treatment increased the lean content in carcasses from low-BW piglets (p < 0.01). The monounsaturated fatty acids concentration was higher in lower-than-normal-BW piglets (48.1% vs. 47.1%; p = 0.002) and the opposite effect was observed for polyunsaturated fatty acids (13.6% vs. 15.7%; p = 0.002). NC treatment induced a higher concentration of n-7 fatty acids. In conclusion, NC treatment may be a useful practice to reduce mortality in low-BW piglets. Moreover, NC could affect carcass fatness and meat quality, thus suggesting a long-term effect on metabolism.

Transcriptome analysis of the effect of pyrroloquinoline quinone disodium (PQQ·Na2) on reproductive performance in sows during gestation and lactation

Background

Pyrroloquinoline quinone (PQQ), which is a water soluble, thermo-stable triglyceride-quinone, is widely distributed in nature and characterized as a mammalian vitamin-like redox cofactor. The objective of this study was to investigate the effects of pyrroloquinoline quinone disodium (PQQ·Na₂) on reproductive performance in sows.

Results

Dietary supplementation with PQQ·Na₂ significantly increased the total number of piglets born, the number of piglets born alive and the born alive litter weight. It also increased the antioxidant status in the placenta, plasma and milk. The concentration of NO was significantly increased in the plasma and placenta. RNA-seq analysis showed that 462 unigenes were differentially expressed between the control (Con) treatment and PQQ treatment groups. Among these unigenes, 199 were upregulated, while 263 unigenes were downregulated. The assigned functions of the unigenes covered a broad range of GO categories. Reproduction (27, 7.03%) and the reproduction process (27, 7.03%) were assigned to the biological process category. By matching DEGs to the KEGG database, we identified 29 pathways.

Conclusions

In conclusion, dietary supplementation with PQQ·Na₂ in gestating and lactating sows had positive effects on their reproductive performance.

Electronic supplementary material

The online version of this article (10.1186/s40104-019-0369-y) contains supplementary material, which is available to authorized users.

Effects of increased energy and amino acid intake in late gestation on reproductive performance, milk composition, metabolic, and redox status of sows1

The objective of this study was to determine the effects of increased AA and energy intake during late gestation on reproductive performance, milk composition, and metabolic and redox status of sows. A total of 118 Yorkshire sows (third through sixth parity) were randomly assigned to dietary treatments from day 90 of gestation until farrowing. Dietary treatments consisted of combinations of 2 standardized ileal digestible (SID) AA levels [14.7 or 20.6 g/d SID Lys, SID Lys and other AA met or exceeded the NRC (2012) recommendations] and 2 energy levels (28.24 or 33.78 MJ/d intake of NE) in a 2 × 2 factorial design. After parturition, all sows were fed a standard lactation diet. Blood samples were collected and analyzed for parameters on metabolism, redox status, and amino acid profile. The data were analyzed using the generalized linear mixed models to reveal the impact of dietary levels of energy, AA, and their interaction. Sows with increased intake of AA had greater BW gain (P < 0.01) during late gestation. Furthermore, the BW loss during lactation was increased in sows with increasing intake of energy (P < 0.05) or AA (P < 0.05). Sows fed high energy had higher total litter birth weights (20.2 kg vs. 18.4 kg, P < 0.05) and shorter duration of farrowing (261 min vs. 215 min, P < 0.05), compared with those fed low energy, which likely was due to higher (P < 0.05) plasma glucose and lower (P < 0.05) plasma lactate prior to parturition. High AA intake in late gestation increased the ADG of piglets during the following lactation (P < 0.05), and increased the concentrations of plasma urea, and the following AA: Lys, Met, Thr, Val, Ile, Leu, Phe, Asp, Ser, and Arg at farrowing (P < 0.05). In conclusion, the increased intake of energy increased total litter weight of newborns and shortened the farrowing duration, which likely was due to improved energy status at farrowing. Furthermore, sows with increased intake of AA led to higher growth rate of piglets during the following lactation, accompanying with the increasing levels of plasma urea and amino acids. Therefore, the higher energy intake in late gestation appeared to improve litter weight and farrowing duration, while higher AA intake may have positive effect on piglets performance in lactation.