Homocysteine metabolism, growth performance, and immune responses in suckling and weanling piglets

Effects of sources and routes of administration of vitamins A, D and copper on postnatal status of these micronutrients in piglets

Twenty-six nulliparous sows were fed conventional gestation and lactation diets supplemented (N = 13) or not (N = 13) with extra daily supplements of 25-hydroxy-cholecalciferol (25-OH-D3; 4 ĸIU), β-carotene (24 ĸIU), and copper (Cu)-proteinate (45 mg) from day 90 of gestation to 21 d of lactation (L21). In each litter, 10 piglets were divided into 5 pairs received, at 2 (L2) and 8 d (L8) of age, one of the five combinations of micronutrient sources and routes of administration (N = 260 piglets total). These neonatal treatments (N = 26 pairs or 52 piglets each) consisted of oral vitamin D3, retinol acetate and CuSO4 (T1); oral 25-OH-D3, β-carotene, and Cu proteinate (T2); exposure to ultraviolet light (UVB), oral retinol palmitate and Cu gluconate (T3); intramuscular vitamin D3 and retinyl propionate and oral Cu acetate (T4); oral saline (CTRL). Oral or intramuscular provisions corresponded to 12 mg of Cu and 70 and 12 ĸIU of vitamins A and D, respectively. Blood samples were collected from all piglets at L2, L8, and L21 for determination of serum Cu, retinol, and 25-OH-D3. Body weight was measured at birth, L2, L8, and L21. Piglets were weaned at L21, and liver and blood samples were collected 2 d later to evaluate oxidative enzymes in blood and liver and hepatic ATP concentrations and expression of genes associated with antioxidant status. Sow treatments had marginal or no impacts on Cu, retinol, 25-OH-D3, or antioxidant status in piglet blood serum and liver. However, when supplements were given to piglets, hepatic Cu was 38% greater in for all treated piglets compared to CTRL (P < 0.01), hepatic retinol was 3 times higher in T1 than in CTRL (P < 0.01) and intermediate for other treatments whereas serum 25-OH-D3 was markedly increased with T2 and T3 at L8 and L21, respectively, compared to CTRL (Piglet treatment × Age interaction, P < 0.01). Concerning antioxidant activities, glutathione peroxidase, and superoxide dismutase were increased (P < 0.03) in plasma of T2 piglets whereas the highest values (P < 0.03) for indicators of oxidative damage to proteins were observed in T4 piglets. The study revealed that oral Cu proteinate from T2, oral retinol acetate from T1, oral 25-hydroxy-cholecalciferol from T2, and UVB light exposure from T3 were the most efficient ways of increasing the postnatal status of these micronutrients in suckling piglets and this may have some impacts on their peri-weaning antioxidant status.

Homocysteine-Potential Novel Diagnostic Indicator of Health and Disease in Horses

Homocysteine is an endogenous, non-protein sulfuric amino acid, an intermediate metabolite formed by the methionine transmethylation reaction. Its elevated serum concentration in humans, hyperhomocysteinemia, is a sensitive indicator and a risk factor for coagulation disorders, cardiovascular diseases and dementia. However, the role of homocysteine in veterinary species has not been unequivocally established. Although some research has been conducted in dogs, cats, cattle and pigs, relatively few studies on homocysteine have been conducted in horses. So far, it has been established in this species that homocysteine has an atherogenic effect, plays a role in early embryo mortality and is responsible for the induction of oxidative stress. These preliminary findings support establishing a reference range in a normal population of horses, including horses in training and merit further investigations into the role of this amino acid in health and disease in this species.

Do Micronutrient and Omega-3 Fatty Acid Supplements Affect Human Maternal Immunity during Pregnancy? A Scoping Review

Maternal dietary micronutrients and omega-3 fatty acids support development of the fetal and neonatal immune system. Whether supplementation is similarly beneficial for the mother during gestation has received limited attention. A scoping review of human trials was conducted looking for evidence of biochemical, genomic, and clinical effects of supplementation on the maternal immune system. The authors explored the literature on PubMed, Cochrane Library, and Web of Science databases from 2010 to the present day using PRISMA-ScR methodology. Full-length human trials in English were searched for using general terms and vitamin A, B12, C, D, and E; choline; iodine; iron; selenium; zinc; and docosahexaenoic/eicosapentaenoic acid. Of 1391 unique articles, 36 were eligible for inclusion. Diverse biochemical and epigenomic effects of supplementation were identified that may influence innate and adaptive immunity. Possible clinical benefits were encountered in malaria, HIV infections, anemia, Type 1 diabetes mellitus, and preventing preterm delivery. Only limited publications were identified that directly explored maternal immunity in pregnancy and the effects of micronutrients. None provided a holistic perspective. It is concluded that supplementation may influence biochemical aspects of the maternal immune response and some clinical outcomes, but the evidence from this review is not sufficient to justify changes to current guidelines.

Effect of nutritional status on nutrient and gas utilization by the mammary gland of lactating sows

Milk synthesis being a continuous process in lactating sows, the mammary gland has to adapt its metabolism in response to extreme short-term changes in nutrient availability in the arterial bloodstream, due to the feeding pattern. The objective of the present study was to better quantify and understand these adaptations. The effect of morning refeeding after an overnight 16-h feed withdrawal was measured on the uptake of energy-supplying nutrients, amino acids (AA), and some vitamins and minerals. After farrowing, catheters were fitted in the right anterior mammary vein and in the carotid artery of six sows. Blood samples were drawn on days 7, 14, and 21 of lactation, every 30 from 60 min before the morning meal to 300 min after the morning meal. Plasma concentrations of glucose, lactate, triglycerides (TG), non-esterified fatty acids (NEFA), glycerol, α-amino nitrogen (N), vitamins B₁₂, and folates were determined on all samples. Riboflavin and AA concentrations were only measured 30 min before the meal and 120 min after the meal. Arterial and venous plasma concentrations of glucose, lactate, and α-amino N increased after the meal (P < 0.01), and concentrations of NEFA, glycerol, and TG decreased (P < 0.01). Mammary arteriovenous concentration difference increased after the meal for glucose, lactate, and α-amino N (P < 0.01), remained constant for TG, and decreased for NEFA (P < 0.01) and glycerol (P < 0.05). Arterial concentrations of all AA increased after the meal, but changes of arteriovenous difference with the meal differed among AA. Arteriovenous difference of energy (7.6 kJ/l plasma) concentration was similar in feed-deprived and fed sows, but the contribution of the various nutrients differed, and the respiratory quotient was lower (P < 0.01) before the meal (0.95) than after the meal (1.54). The relative contributions of glucose, lactate, TG, NEFA, and AA to arteriovenous difference in energy concentration were 50.2, 3.8, 25.1, 0, and 20.8% in fed and 24.6, 2.2, 24.9, 32.9, and 15.0% in feed-deprived sows, respectively. The daily mammary extraction of vitamin B₁₂, estimated from arteriovenous differences was higher than the amount of this vitamin bioavailable from the diet, probably contributing to the 50% decrease in plasma concentration between day 7 and day 21 of lactation. For both riboflavin and folates, arteriovenous differences in plasma concentrations were small or not different from zero. These results indicate that the mammary gland has a great capacity to adapt nutrient uptake very rapidly and modify its metabolism according to the nutrients available in the bloodstream.

The combination of nutraceuticals and functional feeds as additives modulates gut microbiota and blood markers associated with immune response and health in weanling piglets

This study aimed to evaluate the effects of a combination of feed additives with complementary functional properties on the intestinal microbiota, homocysteine, and vitamins E and B status as well as systemic immune response of weanling piglets. At weaning, 32 litters were assigned to one of the following dietary treatments (DT): 1) conventional diet (CTRL); 2) CTRL diet supplemented with antibiotics (ATB); 3) a cocktail of feed additives containing cranberry extract, encapsulated carvacrol, yeast-derived products, and extra vitamins A, D, E, and B complex (CKTL); or 4) CKTL diet with bovine colostrum in replacement of plasma proteins (CKTL + COL). Within each litter, the piglets with lowest and highest birth weights (LBW and HBW, respectively) and two piglets of medium birth weight (MBW) were identified. The MBW piglets were euthanized at 42 d of age in order to characterize the ileal and colonic microbiota. Blood samples were also collected at weaning and at 42 d of age from LBW and HBW piglets to measure insulin-like growth factor-1 (IGF-1), cysteine, homocysteine, and vitamins E, B₆, and B₁₂, and to characterize the leukocyte populations. At 42 d of age, cytokine production by stimulated peripheral blood mononuclear cells was also measured. In a second experiment, piglets were reared under commercial conditions to evaluate the effects of the DT on the growth performance. At the indicator species analysis, the highest indicator value (IV) for Succinivibrio dextrinosolvens was found in the CKTL group, whereas the highest IV for Lactobacillus reuteri and Faecalibacterium prausnitzii was evidenced in the CKTL + COL group (P < 0.05). Compared with the other DT, CTRL piglets had higher concentrations of homocysteine, whereas the CKTL and CKTL + COL supplementations increased the concentrations of vitamins E and B₁₂ (P < 0.05). DT had no effect on IGF-1 concentration and on blood leukocytes populations; however, compared with HBW piglets, LBW animals had lower values of IGF-1, whereas the percentages of γδ T lymphocytes and T helper were decreased and increased, respectively (P < 0.05). CKTL + COL also improved the growth performance of piglets reared under commercial conditions (P < 0.05). This study highlights the impact of birth weight on piglet systemic immune defenses and the potential of weaning diet supplemented with feed additives and bovine colostrum to modulate the homocysteine metabolism and the intestinal microbiota.

Maternal perinatal transfer of vitamins and trace elements to piglets

Nursing piglets are entirely dependent, for their micronutrient provisions, upon in utero, colostrum and milk transfers from the dam. An adequate maternal transfer of micronutrients is all the more important during these periods which, in fact, lasts for approximately half the life cycle (conception to slaughter) of modern pigs. The present study aimed to set up a simple approach to assess the maternal perinatal transfer of vitamins and trace elements in sows. Prenatal transfer (R-u) was estimated as limited, passive or active using the ratio between pre-colostral serum concentrations of a given micronutrient in newborn piglets and corresponding pre-farrowing values in sows. Efficiency of the postnatal transfer (R-c) was estimated from the ratio between serum concentrations of post- and pre-colostral micronutrients in piglets. Data from literature (12 studies) were used for vitamins A, D, E, C, folic acid and B12, whereas vitamins B2, B3, B6 and B8 as well as Zn, Fe, Cu and Se were generated from a trial where blood sera from 20 sows, and their litter were collected during the perinatal period. In sow trial, statistical t tests were used to determine if ratios differed from 1. Prenatal transfer was active and in favour of piglets (R-u > 1, P < 0.03) for Zn and vitamins B6 and B8 (sow trial) as well as for vitamins C and B12 (literature data). This transfer was limited (R-u < 1, P < 0.01) for vitamin B2, Fe, Cu and Se (sow trial) and for vitamins A, E, D and folic acid (literature data) whereas it was passive for vitamin B3 (R-u = 1, P > 0.37). After birth, the early postnatal transfer through colostrum was active towards piglets for most micronutrients but vitamins B6 and B8 (R-c < 1, P < 0.01). Globally, the perinatal transfer (combination of R-u and R-c) was favourable to the neonatal piglets for most micronutrients except for vitamins A and D as well as Fe, Cu and Se whereas there is apparently a barrier for prenatal transfer which is not compensated by the colostrum provision to neonatal piglets. Then, post-colostral concentrations of these micronutrients in piglets remain below prenatal levels of their dam. Neonatal strategies of micronutrient provision are known for Fe (intramuscular injection) and Se (sow milk enrichment). Further studies are needed to assess the importance of the unfavourable perinatal transfer for Cu and vitamins A and D for piglet robustness later in life.

Role of homocysteine metabolism in animal reproduction: A review

Homocysteine (Hcy) is a thiol-containing essential amino acid, important for the growth of cells and tissues. Several hypotheses exist regarding Hcy toxicity in humans; Hcy is involved in protein structural modifications, oxidative stress, and neurotoxicity induction and is therefore associated with several pathological conditions in humans. In veterinary science, knowledge regarding Hcy has increased recently due to several studies; however, many aspects remain undiscovered. Many details remain unknown regarding the effect of Hcy levels on pregnancy and the optimal management of pathological conditions associated with Hcy levels during pregnancy in various species. In this review, we aimed to compile various studies on Hcy metabolism to elucidate its current status in the veterinary field, particularly for ovine, bovine, equine, porcine, canine, and feline species.

Lessons from animal nutritionists: dietary amino acid requirement studies and considerations for healthy aging studies

Dietary restriction (DR) increases median life span and protects against age-related disease. Improved longevity can be achieved by restriction of dietary energy, protein, or amino acids (AAs), such as methionine (Met). Met requirements have been defined using methodologies that measure the dose response to Met when all other dietary variables are held constant and with outcomes focused on protein turnover. Here, we cover protein and sulfur AA requirements and discuss the terms "deficient," "optimal," and "excess" and how these need to be considered. We additionally discuss the effect of methyl-donating compounds on sulfur AA metabolism and outcomes. We will discuss how the mechanistic target of rapamycin complex 1 (mTORC1) signaling network regulates protein turnover, lipogenesis and cell growth, proliferation, differentiation, and metabolism in response to hormones, AAs, and cellular energy status. Inhibition of mTORC1 signaling with rapamycin or genetic mutation increases median life span in model organisms, and mTORC1 inhibition may be responsible for some of the life span-extending effects of DR. Finally, we discuss how the sulfur AAs may regulate aspects of reactive oxygen species (ROS) mitigation. Overall, we suggest that approaches evaluating AA intake need to consider whole-body protein synthesis and measures related to tissue-specific and whole-body metabolism that have been associated with longevity.

Oral supplementations of betaine, choline, creatine and vitamin B6 and their influence on the development of homocysteinaemia in neonatal piglets

Homocysteine (Hcy) is an intermediary sulphur amino acid recognised for pro-oxidative properties in several species which may weaken immune competence in piglets. In this species, there is an acute 10-fold increase of concentrations of plasma Hcy (pHcy) during the first 2 weeks of life. The present experiment aimed to determine if pHcy in piglets can be regulated by oral supplementations of betaine as a methyl group supplier, creatine for reducing the demand for methyl groups, choline with both previous functions and vitamin B₆ as enzymic co-factor for Hcy catabolism. A total of seventeen sows (second parity) were fed gestation and lactation diets supplemented with folic acid (10 mg/kg) and vitamin B₁₂ (150 µg/kg). Eight piglets in each litter received daily one of the eight following oral treatments (mg/kg body weight): (1) control (saline); (2) betaine (50); (3) choline (70); (4) creatine (300); (5) pyridoxine (0·2); (6) treatments 2 and 5; (7) treatments 3 and 4; and (8) treatments 2, 3, 4 and 5. According to age, pHcy increased sharply from 2·48 µm at birth to 17·96 µm at 21 d of age (P < 0·01). Concentrations of pHcy tended to be lower (P = 0·09) in treated than in control piglets but the highest and sole pairwise significant decrease (23 %) was observed between treatments 1 and 8 (P = 0·03). Growth from birth to 21 d of age was not influenced by treatments (P > 0·70). Therefore, it appears possible to reduce pHcy concentrations in suckling piglets but a combination of all chosen nutrients is required.