Enhancement of antibody synthesis in rats by feeding cis-9,trans-11 conjugated linoleic acid during early life

The Effect of Supplementation Using a Mixture of Fish Oil and Linseed on the Level of Immunomodulatory Components in Bovine Colostrum

The aim of this study was to determine the effect of supplementing rations, with a mixture of fish oil and linseed, on the level of immunomodulatory components in colostrum. Twenty multiparous cows, that were three weeks before scheduled calving, had a body condition of 3-3.5, and had not been diagnosed with multiple pregnancies, were qualified for the experiment. The cows were divided into two groups: experimental (FOL) (n = 10) and control (CTL) (n = 10). The CTL group were individually given the standard food ration for dry cows for about 21 days before calving, while the FOL group received food rations that were enriched with 150 g of fish oil and 250 g of linseed (golden variety). Colostrum samples for testing were taken twice a day on the first and second days of lactation, and then once a day from the third to the fifth day of lactation. The experiment showed that the applied supplementation had an impact, in the form of increasing the fat, protein, IgG, IgA, IgM, vitamin A, C22:6 n-3 (DHA), and C18:2 cis9 trans11 (CLA) contents in colostrum; however, the C18: 2 n-6 (LA) and C20:4 n-6 (AA) contents decreased. Due to the lower quality of colostrum found in high-yield cows, and therefore in the Holstein-Friesian breed, it is possible to improve the quality by, among other things, introducing nutritional modifications during the second stage of the dry period.

Effects of the Partial Substitution of Corn with Wheat or Barley on the Growth Performance, Blood Antioxidant Capacity, Intestinal Health and Fecal Microbial Composition of Growing Pigs

This experiment aimed to investigate the effects of wheat and barley substitution for corn on growth performance, blood antioxidant capacity, intestinal health and fecal microbial composition in growing pigs. Eighteen healthy “Duroc × Landrace × Yorkshire” pigs (50 ± 0.85 kg) were randomly divided into three groups with six replicates and one pig per replicate. The three treatment groups were fed the basal diet (CON) based on corn and soybean meal, respectively, and the experimental group diet was partially replaced by wheat (WH) and barley (BL), respectively. The nutritional levels of the three treatments were the same. The experiment lasted 28 days. Wheat and barley partially replacing corn had no significant effects on growing pigs’ growth performance, blood antioxidant capacity and nutrient digestibility (p > 0.05). Compared with CON and BL, WH significantly increased the duodenal villus height and villus height/crypt depth ratio of growing pigs (p < 0.05). Compared with CON, WH and BL significantly increased the contents of butyric acid, propionic acid and total volatile fatty acid (VFA) in the cecum and colonic digesta of growing pigs (p < 0.05). In addition, the abundance of Turicibacter, Escherichia-Shigella and other harmful bacteria in barley and wheat diet groups were significantly decreased at the genus level (p < 0.05). The abundance of Bifidobacterium, Lactobacillus, Prevotella and Roseburia increased significantly (p < 0.05). In conclusion, barley and wheat partially replacing corn as energy feedstuffs does not affect the growth performance of pigs but can regulate intestinal flora and promote intestinal health.

Comparative Effects of Compound Enzyme and Antibiotics on Growth Performance, Nutrient Digestibility, Blood Biochemical Index, and Intestinal Health in Weaned Pigs

This experiment aims to explore the effects of compound enzyme preparation substituting chlortetracycline on growth performance, serum immune markers, and antioxidant capacity and intestinal health in weaned piglets. A total of twenty-four 28-day-old “Duroc × Landrace × Yorkshire” weaned piglets with an average initial weight of 7.25 ± 0.25 kg were randomly divided into three groups according to their body weight, with eight replicates in each group and one pig in each replicate. The three dietary treatments were basal diet (CON), basal diet + 1,000 mg/kg compound enzyme preparation (cellulase 4,000 IU/g, α-amylase 1,000 IU/g, β-glucanase 150 IU/g, and neutral protease 3,000 IU/g, CE), and basal diet + 75 mg/kg chlortetracycline (CTC). The animal experiment lasted for 28 days and was divided into two stages: the early stage (0–14 days) and the late stage (15–28 days). The results showed that (1) compared with the CON, the CE and CTC significantly increased the ADG of weaned piglets during the early and whole period of experiment (p < 0.05), decreased the F:G in the whole experiment period (p < 0.05), and diarrhea rate in the early stage (p < 0.01). (2) Compared with the CON, the apparent total tract digestibility of ADF and NDF was significantly increased in pigs fed the CE diet in the early and late stages of experiment (p < 0.05) with no significant difference compared with the CTC. (3) Compared with the CON, the concentrations of serum IgA and SOD in weaned piglets were significantly increased in the CE group in the early stage of the experiment (p < 0.05). (4) Compared with the CON group, the acetic acid, propionic acid, and total VFA contents in cecum and colon segments were elevated in the CE group (p < 0.05) with no significant difference compared with the CTC. (5) Compared with the CON group, the villus height of duodenum and jejunum and the ratio of villus height to recess depth of ileum were increased in the CE and CTC group (p < 0.05). (6) Compared with the CON group, the abundance of Lactobacillus significantly increased (p < 0.01) while the abundance of Escherichia coli decreased in the CE group and CTC group (p < 0.01). In conclusion, CE preparation instead of CTC can significantly improve the nutrient digestibility, the immunity, antioxidant capacity, and intestinal health of pigs, which may contribute to the improved growth performance of piglets.

Effects of dietary CLA supplementation, parity and different concentrate levels before calving on immunoglobulin G1, G2 and M concentrations in dairy cows

Peripartal dairy cows exhibit a higher susceptibility for infectious diseases, which might be linked to the negative energy balance occurring at the onset of lactation. A dietary supplementation of conjugated linoleic acids (CLA) may reduce milk fat yield and subsequently lower the energy deficit. The utilization of immunoglobulins (Ig) for colostrogenesis might impair humoral immunity in peripartal dairy cows; therefore this study investigated the effects of a CLA supplement, parity and different dietary energy levels on plasma and colostrum IgG1, IgG2 and IgM levels in dairy cows and their calves. Blood samples were collected from 64 cows from 21days before until 56days after parturition and colostrum samples for the first 3days of lactation. Plasma immunoglobulin concentrations of 19 calves were determined before colostrum uptake. Neither plasma IgG1, nor IgG2 levels were affected by CLA or dietary energy level. However, immunoglobulin levels were affected by parity. Heifers possessed the lowest IgG1 concentrations. IgG2 concentrations were highest in cows with 2 lactations prior to parturition and in heifers after parturition. Plasma IgM levels were characterized by a sharp decrease 3days prior to parturition and were scarcely affected by the feeding regimen or parity. Generally, immunoglobulin levels appear to be mostly independent from the peripartal energy balance of the cows and are not influenced by dietary CLA. However, pronounced differences among parities for IgG1 and IgG2 were revealed which should be further evaluated.

Goat milk fat naturally enriched with conjugated linoleic acid increased lipoproteins and reduced triacylglycerol in rats

Goat milk is source of different lipids, including conjugated linoleic acid (CLA). CLA reduces body fat and protect against cardiovascular diseases. In the present study fat from goat milk naturally enriched with CLA was used. Male Wistar rats were divided into three groups that received during a 10 week diet with different lipid sources: soybean oil (CON), coconut oil (CO) and goat milk fat naturally enriched with CLA (GM-CLA). We evaluated the effects of a GM-CLA on biochemistry parameters - high density lipoprotein (HDL), triacylglycerol (TAG), TAG/HDL ratio, total cholesterol and glucose -, body weight and histopathological aspects of the intestine and liver. GM-CLA increased body weight from the second to the fifth week of the experiment compared to CON. Feed intake differed between the CON group and GM-CLA early in the first to third week of the experiments and later between the ninth and tenth week. The CLA-diet group showed increased levels of HDL, reduced levels of TAG and TAG/HDL ratio and no effect on LDL, but enhanced total cholesterol. Serum glucose of the GM-CLA group showed no difference from the control group. Thus, a GM-CLA diet promoted growth in young rats and acted as protector of cardiovascular function, but further studies are still needed to clarify these effects.

The suckling rat as a model for immunonutrition studies in early life

Diet plays a crucial role in maintaining optimal immune function. Research demonstrates the immunomodulatory properties and mechanisms of particular nutrients; however, these aspects are studied less in early life, when diet may exert an important role in the immune development of the neonate. Besides the limited data from epidemiological and human interventional trials in early life, animal models hold the key to increase the current knowledge about this interaction in this particular period. This paper reports the potential of the suckling rat as a model for immunonutrition studies in early life. In particular, it describes the main changes in the systemic and mucosal immune system development during rat suckling and allows some of these elements to be established as target biomarkers for studying the influence of particular nutrients. Different approaches to evaluate these immune effects, including the manipulation of the maternal diet during gestation and/or lactation or feeding the nutrient directly to the pups, are also described in detail. In summary, this paper provides investigators with useful tools for better designing experimental approaches focused on nutrition in early life for programming and immune development by using the suckling rat as a model.

Gene expression profiles in rat mesenteric lymph nodes upon supplementation with conjugated linoleic acid during gestation and suckling

Background

Diet plays a role on the development of the immune system, and polyunsaturated fatty acids can modulate the expression of a variety of genes. Human milk contains conjugated linoleic acid (CLA), a fatty acid that seems to contribute to immune development. Indeed, recent studies carried out in our group in suckling animals have shown that the immune function is enhanced after feeding them with an 80:20 isomer mix composed of c9,t11 and t10,c12 CLA. However, little work has been done on the effects of CLA on gene expression, and even less regarding immune system development in early life.

Results

The expression profile of mesenteric lymph nodes from animals supplemented with CLA during gestation and suckling through dam's milk (Group A) or by oral gavage (Group B), supplemented just during suckling (Group C) and control animals (Group D) was determined with the aid of the specific GeneChip^® Rat Genome 230 2.0 (Affymettrix). Bioinformatics analyses were performed using the GeneSpring GX software package v10.0.2 and lead to the identification of 89 genes differentially expressed in all three dietary approaches. Generation of a biological association network evidenced several genes, such as connective tissue growth factor (Ctgf), tissue inhibitor of metalloproteinase 1 (Timp1), galanin (Gal), synaptotagmin 1 (Syt1), growth factor receptor bound protein 2 (Grb2), actin gamma 2 (Actg2) and smooth muscle alpha actin (Acta2), as highly interconnected nodes of the resulting network. Gene underexpression was confirmed by Real-Time RT-PCR.

Conclusions

Ctgf, Timp1, Gal and Syt1, among others, are genes modulated by CLA supplementation that may have a role on mucosal immune responses in early life.