The influence of parity, body condition, litter size and carbetocin administration on colostrum production and immunoglobulin levels in highly productive sows within a tropical environment.

The aim of this study was to explore the factors contributing to colostrum production and the levels of colostrum immunoglobulins (IgG and IgA) in contemporary highly productive sows within a tropical climate. We focused on variables such as parity number, litter size, sow body condition score (BCS), the timing of sample collection following the commencement of farrowing and the use of carbetocin during the birthing process. A total of 100 colostrum samples were collected from a group of 50 Danish Landrace × Yorkshire crossbred sows. These samples were taken at two distinct time intervals: right after farrowing (0 h) and 6 h later. The colostrum samples were classified according to the sows' parity numbers, with 33 samples originating from primiparous sows and 67 from multiparous ones. Additionally, the number of live-born piglets were categorized into three groups: 7-13, 14-17 and ≥ 18 piglets per litter. Moreover, the samples were categorized based on the use of carbetocin during the birthing process, with 34 sows experiencing natural farrowing and 66 sows receiving carbetocin. The sow's BCS was assessed through visual evaluation and palpation. The piglet colostrum consumption and the amount of colostrum produced by the sows were determined. The concentrations of IgG and IgA were determined by using the enzyme-linked immunosorbent assay (ELISA) technique. On average, the colostrum production averaged 5.5 ± 1.7 kg, with IgG and IgA concentrations averaging 54.9 ± 24.6 mg/ml and 7.6 ± 3.5 mg/ml, respectively. Primiparous sows exhibited a significant 25.2% decrease in IgG concentration within 6 h of parturition (P < 0.05), whereas no such decline was observed in multiparous sows. Furthermore, multiparous sows displayed higher colostrum yields (6.2 ± 1.5 kg and 4.3 ± 1.5 kg, respectively, P < 0.001) and IgA concentrations compared to primiparous sows (8.3 ± 3.8 mg/ml and 6.3 ± 2.6 mg/ml, respectively, P = 0.002). Furthermore, a positive correlation was observed between IgA concentrations in colostrum and the sow's BCS at both the 0-h and 6-h post-farrowing time points (r = 0.425, P = 0.002 and r = 0.315, P = 0.031, respectively). The administration of carbetocin did not yield a significant impact on the concentrations of IgG and IgA in the sows' colostrum (P > 0.05). In conclusion, during the initial 6 h after birth, colostrum IgA levels remained stable, whereas there was a noticeable decline in IgG levels, particularly among primiparous sows. The production volume of colostrum and the concentration of IgA in sows within tropical conditions were influenced by both parity number and body condition score.

Factors affecting birth weight and stillbirth in sows housed in a tropical environment.

This study analysed data from a commercial swine herd in Thailand equipped with a free-farrowing housing system, comprising 17,196 piglets from 1318 litters, to explore the impact of sow and litter characteristics on the piglet birth weight and the incidence of stillbirth. The piglets were classified into four groups based on the total number of piglets born per litter (TB): ≤9 (n = 1434), 10-12 (n = 3232), 13-15 (n = 6537) and ≥16 (n = 5993). Sows were classified into four groups based on parity number: 1, 2-4, 5-7 and ≥8. The piglets were categorized into quartiles based on their birth order ranking: Q1 (n = 4786), Q2 (n = 4143), Q3 (n = 3808) and Q4 (n = 4456). Piglet birth weight was individually measured before colostrum ingestion. On average, TB, the number of live-born piglets and the incidence of stillbirth were 13.1 ± 3.7, 11.5 ± 3.8 and 6.3%, respectively. Among these litters, 26.6% had TB numbers ≥16. The average piglet birth weight was 1.37 ± 0.36 kg, with 18.3% of piglets weighing ≤1.0 kg at birth. Piglet birth weight was influenced by birth order ranking, as Q4 piglets were found to be heavier than piglets born in Q1-Q3 (p < .001). Moreover, the percentage of piglets with a birth weight of ≤1.0 kg increased from 5.9% in litters with TB of ≤9-25.3% in litters with TB of ≥16 (p < .001). Additionally, primiparous sows had lower piglet birth weights compared to sows with parity numbers 2-4, 5-7 and ≥8 (p < .001). Piglets born in the fourth quartile (Q4) had a higher risk of stillbirth compared to those born in the first (Q1), second (Q2) and third (Q3) quartiles (12.5% vs. 2.2%, 4.1% and 6.6%, respectively, p < .001). The incidence of stillbirth in litters with TB ≥16 was also higher than that in litters with TB ≤9 and 10-12 (p < .05). Furthermore, sows with parity numbers ≥8 had a higher incidence of stillbirth (9.7%) compared to primiparous sows (4.0%, p < .001), sows with 2-4 parity (5.2%, p < .001) and sows with 5-7 parity (7.6%, p = .003). In summary, a high incidence of stillbirth was found in piglets born in the last quartile of litters, in litters with >16 piglets and for sows with parity numbers ≥8. Piglets born in the last quartile of litters were heavier than those born in the first to third quartiles.

Dietary supplementation with garcinol during late gestation alleviates disorders of bile acid metabolism and improves the performance of sows and newborn piglets.

The present study was conducted to evaluate the effects of dietary garcinol supplementation during late gestation on bile acid metabolism and performance of sows. Sixty sows (Duroc × Yorkshire × Landrace; second- or third-parity; n = 20) with disorder of bile acid metabolism were randomly divided into three groups: control diet (CON; basal diet), basal diet with 200 mg garcinol (Low Gar), and basal diet with 600 mg garcinol (High Gar) per kg of feed. The body weight (BW); backfat thickness and litter size of the sows; and birth weight, weaning weight, and mortality of piglets were recorded. Sows' blood was collected for the measurements of hematological parameters and antioxidative and immune indexes, and indicators related to bile acid metabolism, respectively. The colostrum and fecal samples of the sows were also collected for analysis of colostrum composition and apparent total tract nutrient digestibility. Garcinol had no effect on the BW and backfat thickness of the sows but significantly decreased the mortality and number of weak litter (P < 0.05). Moreover, the white blood cell counts, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activity in the plasma of the sows were increased more significantly (P < 0.05) in the garcinol groups than that in the CON group, whereas the malondialdehyde (MDA) content was decreased (P < 0.05). Dietary supplementation with garcinol significantly reduced TBA concentrations (P < 0.05). The content of immunoglobulin A (IgA) and immunoglobulin G (IgG) in the plasma and in colostrum of sows were increased more significantly (P < 0.05) in the garcinol groups than that in the CON group. In addition, dry matter (DM), Ash, and EE in the colostrum were similar between groups (P > 0.05), whereas the garcinol significantly increased the crude protein (CP) in the colostrum. The apparent total tract nutrient digestibility was similar between treatments. Garcinol treatment induced a gradually decreased (P > 0.05) the expression of genes involved in BA synthesis (CYP7A1, CYP8B1), BA uptake (NTCP, OATP1A2), BA secretion (BSEP and MRP2), BA detoxification (SULT2A1), and BA efflux into the blood circulation (OSTß). Collectively, this study indicates that sows fed with garcinol in late gestation showed relieved bile acid metabolism disorder and improved sows performance, antioxidative status, colostrum protein content, showing promise in natural plant extract nutrition for sows with disorder of bile acid metabolism.

The elevated maternal serum bile acid (BA) levels in late gestation leads to accumulation of BA in fetal tissues, and thus increases the risk of fetal mortality and metabolic disease of offspring. It has confirmed that BA disordered and oxidative damage are intimately related. Thus, studies about alleviating oxidative stress and facilitating BA metabolism in pregnant sows can be relevant. As an excellent antioxidative plant extract, garcinol has been widely used in dietary supplementation of rodents; however, the effect of dietary supplementation with garcinol on the bile acids disorders of sows in late gestation has rarely been reported. The present study provides the first evidence that dietary supplementation with garcinol during late gestation improved maternal BA metabolism of sows with disorder of BA metabolism, as well as the health and antioxidative status, colostrum protein content, showing promise in natural plant extract nutrition for sows with disorder of bile acid metabolism.

Comparative Hypothalamic Transcriptome Analysis Reveals Crucial mRNAs, lncRNAs, and circRNAs Affecting Litter Size in Goats.

Litter size is an important indicator to measure the reproductive performance of goats, which is affected by the reproductive function of animals. The hypothalamus, as the regulatory center of the endocrine system, plays an important role in the reproduction of female animals. Here, we performed high-throughput RNA sequencing using hypothalamic tissue from high-fecundity and low-fecundity Leizhou goats to explore critical functional genes associated with litter size. Differentially expressed mRNA, lncRNA, and circRNAs were screened using DESeq and were enriched, and then analyzed by Gene Ontology and Kyoto Encyclopedia of Gene and Genome. Results showed that some of these differentially expressed mRNAs could be enriched in reproductive processes, jak-STAT, prolactin signaling pathway, and other signaling pathways related to reproduction, such as SOCS3. Furthermore, the central proteins POSTN, MFAP5, and DCN from protein-protein interaction may regulate animal reproductive activity by affecting cell proliferation and apoptosis. lncRNA MSTRG.33887.2 as well as circRNAs chicirc_098002, chicirc_072583, and chicirc_053531 may be able to influence animal reproduction by participating in folate metabolism and energy metabolism homeostasis through their respective target genes. Our results expand the molecular mechanism of hypothalamic regulation on animal reproduction.

Effects of lactation number and litter size on the chemical composition and immune components of goat colostrum.

This study aimed to evaluate the effect of the number of lactations and litter size on the chemical composition, immunoglobulins, and cytokines of goat colostrum. The experiment was conducted at the Animal Research Base, Mianyang Academy of Agricultural Sciences, from February to March 2021. After delivery, 48 colostrum samples were obtained every 24 h by manual milking from both udders. The contents of colostrum proteins, IgA, and IgM increased markedly up to 48 h postpartum, reaching 250 and 1250 µg/mL, respectively (p < 0.01 compared with 0 h). However, the total Ig and IgG contents dropped quickly at 48 h postpartum to around 4.5 and 6 mg/mL, respectively, and continued to do so until 96 h postpartum (p < 0.01). As for litter size, the colostrum DM, fat, total Ig, IgG, INF-γ, and IL-2 of twin-birth goats were higher than those of single-birth goats at 0 h postpartum. Moreover, the colostrum of multiparous goats contained higher total Ig, IgA, IgG, and INF-γ concentrations than that of primiparous goats at 0 h postpartum (p < 0.01). However, the colostrum INF-α and IL-5 contents of multiparous goats were lower than those of primiparous goats at 0 h postpartum (p < 0.05). Available information indicates that colostrum secretion takes place until 48 h postpartum and that the effect of litter size and lactation number on colostrum quality is observed at 0 h postpartum.

Feeding the modern sow to sustain high productivity.

Selection for hyper-prolific sows has increased the litter size by more than 50% during the last three decades, and proper nutrition of the female pigs has concomitantly changed due to improved prolificacy and productivity of gilts and sows. This review summarizes the physiological characteristics and nutritional challenges associated with feeding modern hyper-prolific sows during the gilt rearing period and during gestation, transition, and lactation periods. The review presents up-to-date knowledge of the energy and lysine requirements of female pigs and focuses on how nutrition may increase fat gain and limit protein and weight gain in the gilt rearing period and in early and mid-gestation. In late gestation, fetal and mammary growth should be considered and during the transition, colostrum yield and farrowing performance need to be optimized. Finally, milk production should be optimized and body mobilization should be minimized in the lactation period to achieve high feed efficiency in hyper-prolific sows.

Offspring of hyper prolific sows: Immunity, birthweight, and heterogeneous litters.

In Europe, in the last 3 decades, there has been a constant increase in litter size due to the use of superior maternal line genetics. Those sows giving birth to more piglets than their average number of functional teats are identified as hyperprolific sows (HPS). The large number of piglets born within a litter implies not only a challenge for their access to vital resources like colostrum and milk but has a direct effect on their average birth weight and heterogeneity. These conditions are detrimental to piglets' vitality in the first hours of life and also to their immunity development. An exceptionally large number of growing fetuses in HPS leads to intrauterine crowding and consequently to an increased number of piglets suffering from intrauterine growth retardation (IUGR), which put piglets at a high risk of mortality after birth and up to later stages of life. Increased heterogeneity of birth weight within large litters increases the competition for colostrum intake, with the smaller piglets being less competitive and vital, and therefore affecting negatively their immunity. Low birth weight, long interval to reach the udder, and long duration of farrowing, all have negative effects on piglets' immunoglobulin absorption. In HPS litters, colostrum management should be focused on low birth weight piglets, anticipating their impaired capabilities associated with ingesting adequate colostrum, by shortening the time to reach the udder and reducing competition among piglets. The vitality of neonate piglets, especially low in birth weight or affected by IUGR should be enhanced to improve their body temperature and their early life stage energy metabolism.

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.

Evaluation of essential fatty acids in lactating sow diets on sow reproductive performance, colostrum and milk composition, and piglet survivability.

Mixed parity sows (n = 3,451; PIC, Hendersonville, TN; parities 2 through 9) and their litters were used to evaluate the effects of essential fatty acid (EFA) intake on sow reproductive performance, piglet growth and survivability, and colostrum and milk composition. Our hypothesis, like observed in earlier research, was that increasing linoleic acid (LA) and α-linolenic acid (ALA) would improve sow and litter performance. At approximately day 112 of gestation, sows were randomly assigned within parity groups to 1 of 4 corn-soybean meal-wheat-based lactation diets that contained 0.5 (Control) or 3% choice white grease (CWG), 3% soybean oil (SO), or a combination of 3% soybean oil and 2% choice white grease (Combination). Thus, sows were provided diets with low LA and ALA in diets with CWG or high LA and ALA in diets that included soybean oil. Sows received their assigned EFA treatments until weaning and were then fed a common gestation and lactation diet in the subsequent reproductive cycle. Average daily feed intake during the lactation period increased (P < 0.05) for sows fed the Combination and CWG diets compared with sows fed the Control or SO diet. However, daily LA and ALA intakes of sows fed the Combination and SO diets were still greater (P < 0.05) than those of sows fed 0.5 or 3% CWG. Overall, sows consuming high EFA from the Combination or SO diets produced litters with heavier (P < 0.05) piglet weaning weights and greater (P < 0.05) litter ADG when compared with litters from sows fed diets with CWG that provided low EFA. Despite advantages in growth performance, there was no impact of sow EFA intake on piglet survivability (P > 0.10). Additionally, lactation diet EFA composition did not influence sow colostrum or milk dry matter, crude protein, or crude fat content (P > 0.10). However, LA and ALA content in colostrum and milk increased (P < 0.05) in response to elevated dietary EFA from SO. There was no evidence for differences (P > 0.10) in subsequent sow reproductive or litter performance due to previous lactation EFA intake. In conclusion, increased LA and ALA intake provided by soybean oil during lactation increased overall litter growth and pig weaning weights, reduced sow ADFI, but did not affect piglet survivability or subsequent performance of sows.

Supplemental fat sources are an effective and widely accepted strategy to increase energy density of sow lactation diets that can also provide essential fatty acids such as linoleic acid (LA) and α-linolenic acid (ALA). Currently, the effects of supplemental LA and ALA provided shortly before farrowing on colostrum and milk composition are not fully understood. Additionally, the influence of elevated LA and ALA provided in sow lactation diets on litter growth and survivability responses has not been extensively evaluated. Therefore, this trial was conducted to evaluate the effects of fat sources providing low and high LA and ALA intake on sow performance, litter growth and survivability, colostrum and milk composition, and subsequent reproductive performance. Overall, sows consuming diets with high LA and ALA provided by soybean oil produced litters with heavier piglet weaning weights and greater litter average daily gain when compared with sows consuming diets with low LA and ALA content. Increasing LA and ALA by added soybean oil also increased their content in colostrum and milk. However, there was no influence of sow LA and ALA intake on litter survivability or subsequent reproductive performance of sows.

The model of litter size reduction induces long-term disruption of the gut-brain axis: An explanation for the hyperphagia of Wistar rats of both sexes.

The gut microbiota affects the host's metabolic phenotype, impacting health and disease. The gut-brain axis unites the intestine with the centers of hunger and satiety, affecting the eating behavior. Deregulation of this axis can lead to obesity onset. Litter size reduction is a well-studied model for infant obesity because it causes overnutrition and programs for obesity. We hypothesize that animals raised in small litters (SL) have altered circuitry between the intestine and brain, causing hyperphagia. We investigated vagus nerve activity, the expression of c-Fos, brain-derived neurotrophic factor (BDNF), gastrointestinal (GI) hormone receptors, and content of bacterial phyla and short-chain fatty acids (SCFAs) in the feces of adult male and female Wistar rats overfed during lactation. On the 3rd day after birth, litter size was reduced to 3 pups/litter (SL males or SL females) until weaning. Controls had normal litter size (10 pups/litter: 5 males and 5 females). The rats were killed at 5 months of age. The male and female offspring were analyzed separately. The SL group of both sexes showed higher food consumption and body adiposity than the respective controls. SL animals presented dysbiosis (increased Firmicutes, decreased Bacteroidetes) and had increased vagus nerve activity. Only the SL males had decreased hypothalamic GLP-1 receptor expression, while only the SL females had lower acetate and propionate in the feces and higher CCK receptor expression in the hypothalamus. Thus, overfeeding during lactation differentially changes the gut-brain axis, contributing to hyperphagia of the offspring of both sexes.

Correlations of gestational hemoglobin level, placental trace elements content, and reproductive performances in pregnant sows.

The iron status of sows has a great influence on reproductive performance. Iron deficiency reduces reproductive performance and newborn piglet survival rate of sow. The hemoglobin is a potential predictor for the iron status of sows and is convenient for rapid detection in pig farms. However, the relationship between iron status, hemoglobin, placental trace elements, and reproductive performance remains unclear. In this study, the hemoglobin and reproductive performance of more than 500 sows with first to sixth parities at different gestation stages (25, 55, 75, 95, and 110 d of gestation) in two large-scale sow farms were collected, and the content of placental Fe, Zn, Mn, and Cu was analyzed. The results show that hemoglobin levels of sows during pregnancy (days 75, 95, and 110) decreased significantly (P < 0.001). As the parity increases, the hemoglobin levels of sows at days 25 and 55 of gestation and placental mineral element contents including Fe, Zn, Mn, and Cu at delivery decreased (P < 0.05), while the litter size, birth alive, and litter weights increased gradually (P < 0.001). Furthermore, hemoglobin during pregnancy had a negative linear correlation with litter weight and average weight (P < 0.05), and higher hemoglobin at day 25 of gestation may reduce the number of stillbirths (P = 0.05), but higher hemoglobin at day 110 of gestation may tend to be a benefit for the birth (P = 0.01). And there was a significant positive linear correlation between hemoglobin at day 110 of gestation and placental Fe and Mn levels (P = 0.002, P = 0.013). There was also a significant positive linear correlation among Fe, Zn, Mn, and Cu in the placenta (P < 0.001). The levels of Fe, Zn, and Mn in the placental at delivery were positively related to the average weight of the fetus (P = 0.048, P = 0.027, P = 0.047), and placental Cu was linearly correlated with litter size (P = 0.029). Our research revealed that the requirements for iron during gestation were varied in different gestation periods and parities. The feeds should be adjusted according to the gestation periods, parities, or iron status to meet the iron requirements of sows and fetal pigs.

Iron deficiency and iron excess may cause adverse outcomes during pregnancy. In sows' feed, iron is added as ferrous sulfate, ferrous glycine, or other forms to improve their reproductive performance and prevent iron-deficiency anemia in their offspring. However, it is always ineffective and iron-deficiency anemia often occurs in piglets. To explore the iron requirements in pregnant sows, we conducted a large-scale farm study to track the hemoglobin levels, placental trace element content, and reproductive performances of hundreds of sows. The correlation between the hemoglobin levels, placental trace element content, and reproductive performance indicators of sows during pregnancy at different parities was analyzed. We found that pregnancy hemoglobin level of sows decreases during the gestation and varies at different parities. The hemoglobin level of sows during pregnancy was linearly negatively correlated with reproductive performance. The content of iron, zinc, manganese, and copper in the placenta was linearly positively correlated. Our results revealed that iron deficiency or excess in sows' feed may not be conducive to the improvement of reproductive performance, and the optimal iron supplementation dose during pregnancy may depend on the iron status and number of fetuses of sow.

Folic acid supplementation during pregnancy modulates hepatic methyl metabolism and genes expression profile of neonatal lambs of different litter sizes.

Maternal folic acid (FA) plays an important role in the fetus development, but it is unknown the response of hepatic metabolism in the offspring from different litter sizes to maternal FA supplementation. In the present study, this was done by feeding the ewes with 0, 16 and 32 mg/(kg·DM) FA supplemented diet during pregnancy and analysing the hepatic one-carbon metabolism-related indices and gene expression in the neonatal lambs of different litter sizes (twins, TW; triplets, TR). Regardless of litter sizes, the concentrations of folate, methionine, S-adenosylmethionine and DNA methyltransferase increased significantly, but homocysteine and S-adenosylhomocysteine decreased in the liver of newborn lambs from ewes whose diet was supplemented with FA. In TW, maternal FA status has little effect on hepatic genes expression profile of newborn lambs, and no significant enriched pathway was found. However, DEG involved in cell proliferation such as CCNA2, CCNB2, CCNE2, CDK1 and BUB1 were significantly enriched when the ewes were supplemented with FA in TR groups. In addition, nucleotide synthesis-related genes such as POLD1, POLD2, MCM4 and MCM5 were enriched markedly in DNA replication and pyrimidine metabolism pathways in triplets when a higher FA ingestion [32 mg/(kg·DM)] was implemented in ewes. This finding demonstrated that the hepatic methyl metabolism in TW and TR newborn lambs was regulated by maternal FA status. The hepatic cell proliferation and nucleotide metabolism related genes in TR were more susceptible to maternal dietary FA supplementation during pregnancy.

Effect of Mulberry Leaf powder on reproductive performance, serum indexes and milk amino acid composition in lactating sows.

Experiment was conducted to study the effects of Mulberry Leaf (ML) powder on reproductive performance, serum and milk amino acid composition in sows. Fifty sows (D 85 at gestation) with parity 3 or 4 were randomly divided into 5 groups: C, M100, M200, M300 and M400, receiving 0, 100, 200, 300 and 400 g ML powder per sow per day. Blood and milk of sows at Days 1 and 21 of lactation were collected. Results showed that average daily feed intake (ADFI) during lactation was higher in groups supplemented ML compared with control group (p < 0.01). Litter weight gain during lactation was higher in M400 than in groups M200 and C (p < 0.05), with no significant difference compared with M100 and M300. Serum glucose concentration in groups M400 and M300 was higher than those in the other groups (p < 0.01). Serum HDL-C concentration in group M400 was significantly greater than those in groups M100 and M200 (p < 0.05), with no significant difference between group M400 and groups M300, control. Milk amino acid concentrations such as isoleucine, leucine, lysine and valine were all lower in group M400 than in control (p < 0.01). Serum methionine (Met) concentration was higher in M300 than in other groups (p < 0.01). Milk Met concentration in group C was higher than those of the sows in the group M400, with no significant difference compared with groups M100, M200 and M300 (p < 0.05). Serum Lys and Met concentrations were lower in M400 than in control group (p < 0.05). In summary, our results have revealed the ML supplementation at a high dose such as 300 g/day during later gestation and lactation showed benefit in regulating lipid and amino acid metabolism in sows and then improved growth performance of their offspring.

Review: Improving the performance of neonatal piglets.

Newborn piglets have a high incidence of preweaning mortality that is not only associated with low birth weights but also with the presence of intra-uterine growth-restricted (IUGR) piglets. Such IUGR piglets are commonly seen in litters from hyperprolific sows as a result of insufficient placental transfer of nutrients. Nutritional strategies can be used prior to and during gestation to enhance foetal development and can also be implemented in the transition period to reduce the duration of farrowing and increase colostrum yield. Recent findings showed that the energy status of sows at the onset of farrowing is crucial to diminish stillbirth rate. Newborn piglets often fail to consume enough colostrum to promote thermostability and subsequent growth, and this is particularly problematic in very large litters when there are fewer available teats than the number of suckling piglets. One injection of 75 IU of oxytocin approximately 14 h after farrowing can prolong the colostral phase, hence increasing the supply of immunoglobulins to piglets. Nevertheless, assistance must be provided to piglets after birth in order to increase their chance of survival. Various approaches can be used, such as: (1) optimising the farrowing environment, (2) supervising farrowing and assisting newborn piglets, (3) using cross-fostering techniques, (4) providing nurse sows, and 5) providing artificial milk. Although research advances have been made in developing feeding and management strategies for sows that increase performance of their newborn piglets, much work still remains to be done to ensure that maximal outcomes are achieved.

Lycopene improves maternal reproductive performance by modulating milk composition and placental antioxidative and immune status.

Placental health and milk quality are important for maternal reproductive performance during pregnancy and lactation. Lycopene plays an important role in antioxidation, anti-inflammation and regulating lipid metabolism. The goal of the present study was to investigate the effects of dietary lycopene supplementation in the pig model on reproductive performance, placental health and milk composition during maternal gestation and lactation. In the present study, the litter size of live piglets was increased and the litter size of dead piglets was decreased by lycopene supplementation of the diet of sows. The litter weight at birth and weaning were increased in the lycopene group. Through placental proteomics, we enriched differentially expressed proteins (DEPs), gene ontology (GO) terms, and Kyoto encyclopedia of proteins and genomes (KEGG) pathways involved in immunity, anti-inflammation, antioxidants, and lipid metabolism and transport. Furthermore, in terms of placental health, we analyzed the levels of related enzymes, metabolites and mRNA expression in the placenta. Lycopene was shown to reduce mRNA expression and the levels of placental inflammatory factors, increase the content of immunoglobulin, improve the antioxidant capacity, and improve lipid metabolism and lipid transport in the placenta. In terms of sow milk composition, lycopene increased the levels of immunoglobulins in colostrum and lactose in colostrum and milk. Overall, the results of the present study demonstrate that dietary lycopene supplementation of sows during gestation and lactation improves the reproductive performance to a certain extent; this may be due to lycopene improving the placental health and milk composition of sows.

Free-range system and supplementation of 25-hydroxicholecalciferol increases the performance and serum vitamin levels in mixed-parity sows.

Improvements in sow productivity have raised questions regarding dietary vitamin D recommendations. The present study aimed to evaluate the effects of the housing system with access to sunlight exposure and supplementation of 25-hydroxicholecalciferol on performance and serum levels of 25(OH)D3 in sows during gestation and lactation. Sows were distributed in an experimental design with two housing systems: gestation crates or gestation free-range system with external area for sunlight exposure; and two diets: 0 or 50 µg of 25-hydroxicholecalciferol kg-1 . The use of 25-hydroxicholecalciferol tended (P = 0.052) to improve total born and influenced (P = 0.046) on number of born alive. Litter weight at birth was also increased (P = 0.01) by 25-hydroxicholecalciferol supplementation; 25-hydroxicholecalciferol supplementation and housing system (free-range with sunlight exposure) tended to increase weaning weight (P = 0.07) and litter daily gain (P = 0.051) during lactation. Exposure to sunlight and 25-hydroxicholecalciferol supplementation increased 25(OH)D3 serum levels when compared with control treatment during gestation (136.95 vs. 113.92 ng mL-1 ; P = 0.035) and lactation (120.29 vs. 88.93 ng mL-1 ; P = 0.026). In conclusion, the association of 25-hydroxicholecalciferol supplementation with exposure to sunlight during gestation improved significantly 25(OH)D3 serum levels and consequently performance traits in gestation and lactation.

Composition and physiological functions of the porcine colostrum.

The first secretion, 24-h post parturition of the mammary glands of sows, known as colostrum, is high in protein and low in lactose and fat. As a consequence of an insufficient ingestion of colostrum, more than 50% of piglets fail to reach weaning and die. The composition and some functions of colostrum have been previously reported. For example, colostrum carbohydrates consist of mainly lactose. Lipids in the colostrum are mostly triacylglycerols, but <1% is fatty acids, which may act as homeostasis regulators. Similarly, proteins are found mostly as casein and whey, the latter being ≥80% immunoglobulins. Colostrum-derived immunoglobulins and bioactive proteins such as azurocidin help the immune system of the piglet fend off infections. In addition, leukocytes and exosomes are other minor but nonetheless equally crucial bioactive components in the porcine colostrum. Modern pig farming has achieved increases in pig productivity and litter size, but this has been accomplished in detriment of the health and the survival rate of piglets. Therefore, porcine colostrum is now even more important in pig farming. In the present review, we discuss the current knowledge on the composition and physiological functions of the porcine colostrum and briefly propose future research directions.

Effect of litter birth weight standardization before first suckling on colostrum intake, passive immunization, pre-weaning survival, and growth of the piglets.

Within-litter variation in birth weight is a relevant factor in pig production. This study aimed at comparing pre-weaning mortality, colostrum intake (CI), passive immunization, and growth of piglets from litters of uniform (UN) or heterogeneous (HET) birth weights. The study included 52 multiparous sows (Large White × Landrace) and their litters. Two types of litters were constituted based on birth weight, namely: UN or HET, the control group, using piglets from two to three sows farrowing approximately at the same time. At birth, piglets were weighed, identified, and placed in a box under an IR lamp. At the end of farrowing, piglets were re-weighed and allotted to groups UN or HET (12 per litter) with average weights of 1394 and 1390 g, respectively, and allowed to suckle (time 0). They were re-weighed 24 h later to estimate CI and sows' colostrum yield. At time 0, the average intra-litter CV (%) in weight of experimental litters were 9.3 ±â€¯0.8 (SEM) and 27.8 ±â€¯0.7 in groups UN and HET, respectively (P < 0.001). At 2 days of age, blood samples were taken from the piglets of 11 litters five UN and six HET) and serum Immunoglobulin G (IgG) contents were determined. Mean CI/piglet/litter was similar in both groups, that is, 415 ±â€¯13 in UN and 395 ±â€¯13 g in HET (P = 0.28), but was less variable in UN litters (CV = 22.4 ±â€¯2 vs 36.0 ±â€¯2%, P < 0.001). The IgG levels at 2 days of age were higher in piglets from UN litters (22.5 ±â€¯0.8 vs 18.4 ±â€¯0.7 g/l; P < 0.001) but the CV of IgG levels was not different between litter type (P= 0.46). Mortality up to 21 days of age was lower in UN litters (6.4 vs 11.9%, P = 0.03). The BW at 21 days was not different between litter type (P = 0.25) but it was less variable among piglets from UN litters (CV: 17.1 ±â€¯1.3 vs 25.7 ±â€¯1.3%; P = 0.01). Results reveal that CI is less variable and mortality is lower in piglets from litters of UN birth weight. The results infer that genetic improvement to decrease variation in birth weight within-litter could have a positive effect on homogeneous CI and thus contribute to reducing piglet mortality.

Neonatal overfeeding reduces estradiol plasma levels and disrupts noradrenergic-kisspeptin-GnRH pathway and fertility in adult female rats.

This work evaluated the effects of neonatal overfeeding, induced by litter size reduction, on fertility and the noradrenaline-kisspeptin-gonadotrophin releasing hormone (GnRH) pathway in adult female rats. The litter size was adjusted to 3 pups with each mother in the small litters (SL) and 10 pups with each mother in the normal litters (NL). SL females exhibited metabolic changes associated with reproductive dysfunctions, shown by earlier vaginal opening and first estrus, later regular cyclicity onset, and lower and higher occurrences of estrus and diestrus phases, respectively, as well as reduced fertility, estradiol plasma levels, and mRNA expressions of tyrosine hydroxylase in the locus coeruleus, kisspeptin, and GnRH in the preoptic area in adult females in the afternoon of proestrus. These results suggest that neonatal overfeeding in female rats promotes reproductive dysfunctions in adulthood, such as lower estradiol plasma levels associated with impairments in fertility and noradrenaline-kisspeptin-GnRH pathway during positive feedback.

IGF-1 concentrations after weaning in young sows fed different pre-mating diets are positively associated with piglet mean birth weight at subsequent farrowing.

Pre-mating diets can influence piglet birth weight and within-litter birth weight variation and thereby piglet survival and development. The major objective of this study was to evaluate the litter characteristics of young sows whose pre-mating diets received different supplementation. The supplements included a top-dressing of 200 g, consisting of either wheat (CON) or wheat plus microfibrillated cellulose, L-carnitine or L-arginine at one of two supplementation levels (low and high) in late lactation and during the weaning-to-oestrus interval (WEI). The second objective was to investigate the role of body condition loss and IGF-1 concentration during the WEI for subsequent litter characteristics. In total, sows after their first (N =41) and second (N =15) lactation were used. One week before weaning, the sows were allocated to the seven treatments based on the number of piglets and BW loss from farrowing until 1 week before weaning. Pre-mating diets did not affect litter characteristics at subsequent farrowing. However, at subsequent farrowing, sows after their first lactation had a lower total number of piglets born per litter (18.3 v. 20.3), higher mean piglet birth weight (1365 v. 1253 g), lower CV of birth weight (20.0 v. 26.1%) and lower percentage of piglets <1000 g (11.5 v. 24.4%) than sows after their second lactation. Litter weight at second parturition was positively related to IGF-1 during the WEI after first lactation (P <0.04). Within parity, piglet mean birth weight was positively related to IGF-1 at oestrus (P <0.02). Surprisingly, within parity, a higher relative loin muscle depth loss during previous lactation was related to lower CV and SD of birth weight (P <0.05, for both). In conclusion, pre-mating diets did not affect litter characteristics at subsequent birth. However, a higher IGF-1 concentration during the WEI was positively associated with subsequent litter weight and piglet mean birth weight. Further studies should elucidate the role of IGF-1 during the WEI for subsequent litter characteristics and dietary interventions to stimulate IGF-1.