Effects of the dietary proportions of lipids and carbohydrates on milk fat, blood metabolites, and the fecal microbial community in lactating jennies

Simple SummaryIn this study, we elucidated the changes in metabolites and microbial communities in pregnant ewes during early gestation, and tried to find new biomarkers to predict early pregnancy in sheep. Significant differences were found in the blood biochemical parameters and blood metabolites, but not in the faecal microbial community. At the same time, five potential pregnancy biomarkers were found to predict early pregnancy in ewes. These detected differences will provide a scientific theoretical basis for the rational nutritional regulation of farmers, and these newly discovered biomarkers will promote the development of technology for detecting early pregnancy in sheep in highly cold areas.Ewes undergo complex metabolic changes during pregnancy. Understanding the specific process of these changes is a necessary prerequisite in ewes for regulating and intervening in order to maintain pregnancies. However, there have been relatively few studies on the specific changes that occur in nutritional metabolism in pregnant ewes during early gestation, especially for some landrace ewes in highly cold areas. Therefore, this study aimed to (1) elucidate the changes in metabolites and microbial communities in pregnant ewes during early gestation using metabolomics and 16S ribosomal RNA gene (rDNA) amplicon sequencing approaches, and to (2) discover novel early pregnancy-induced biomarkers in the blood and faeces. Rams were placed together with ewes on D0 and removed on D45. During early gestation, blood and faecal samples were collected from ewes in a highly cold area for analysing the metabolites and microbial communities; these were retrospectively classified as the early gestation pregnant (EP) ewe group or the nonpregnant (NP) ewe group based on the lambing status recorded during the expected delivery period. The differences in the plasma biochemical parameters, plasma metabolites, and faecal microbial communities of pregnant and nonpregnant ewes were characterised. The GC, IL-6, O-acetyl-l-serine, L-glutamine, and 6-acetamido-2-oxohexanoic acid were screened out as potential biomarkers for evaluating the occurrence of early pregnancy. These novel early pregnancy-induced metabolites discovered in ewes might allow for the development of technologies to detect early pregnancies in sheep in highly cold areas.

A single faecal microbiota transplantation modulates the microbiome and improves clinical manifestations in a rat model of colitis.

Effects of Feed Delivery Time on Feed Intake, Milk Production, and Blood Metabolites of Dairy Cows

The objective of this study was to determine the effects of diets having different fermentability on blood gases, blood metabolites and ruminal fermentation parameters in Holstein dairy cows. Four multiparous Holstein dairy cows (665 ± 25 kg BW, 170 ± 7.0 DIM and 15±1.5 kg of milk yield), fitted with rumen cannulae, were used in a 4×4 Latin Square design with 28-d periods. Corn starch and sucrose were added to diets and corn starch was replaced with sucrose at 0 (diet 1), 25 (diet 2), 50 (diet 3) and 75 g (diet 4) per kg diet dry matter in diets containing 600g concentrate and 400g forage. Dry matter intake (DMI), body weight changes (BWC) and milk yield were not affected by the diets (P > 0.05). Milk fat content increased by replacing starch with sucrose (P ≤ 0.05). Milk protein concentration (%) tended to increase by replacing starch with sucrose (P = 0.06). Inclusion of sucrose in the diet did not affect ruminal pH (averaged 6.41) but reduced (P ≤ 0.05) ruminal NH3-N concentration. Total volatile fatty acids (VFA) and molar proportion of most of the individual VFA were unaffected by diets except for the molar proportion of butyrate that was increased with increasing levels of sucrose (P ≤ 0.05). Total branched chain VFA also tended (P = 0.06) to increase with sugar levels. Blood gases and metabolites were not affected but blood urea N which was decreased (P ≤ 0.05) by increasing the level of sucrose in the diets. In conclusion, dairy cows fed diets containing sucrose had lower ruminal NH3 and BUN concentrations without any adverse effects on rumen fermentation characteristics, and blood gases and metabolites. This indirectly shows reduced nitrogen excretion to the environment which is critical for decreasing environmental pollution.

Replacing corn with full-fat corn germ in a basal diet containing cactus (Opuntia stricta) cladodes and sugarcane as forage sources induces milk fat depression associated with the trans-10 shift in dairy cows

The objective of this study was to investigate the effects of pistachio by-products (PBP) in replacement of alfalfa hay (AH) on ruminal fermentation, blood metabolites, and milk fatty acid composition in Saanen dairy goats fed a diet containing fish oil. For this purpose, 15 multiparous lactating Saanen goats (on day 25 postpartum, 38.15±1.2 kg) were randomly assigned to three treatment diets in a completely randomized design with five goats per treatment. The treatment consisted of feeding the following diets: (1) control (AH), (2) 30% PBP, and (3) 30% PBP + polyethylene glycol (PEG, 1 g/Kg of dry matter [DM]). The experiment lasted 21 days, including 16 days of adaptation to the experimental diets followed by a five-day sampling period for determining milk yield and composition, dry matter intake (DMI), and blood metabolites. The results showed that DMI was affected (P<0.05) by using PBP in the diets. The goats fed PBP had a lower (P<0.05) DMI than those in other treatments. No differences were observed in milk yield and composition among the dietary treatments. The goats fed PBP (with and without PEG) had higher (P<0.05) amounts of C16:0 and trans-C18:1 isomer in their milk fat than those fed AH. C24:0 was detected at higher (P<0.05) concentrations in goats fed AH than those in other treatments. Overall, different treatments had no significant effects on the concentrations of saturated, monounsaturated, and polyunsaturated fatty acids (PUFA) in milk fat. Trans fatty acids (TFA) in milk fat exhibited higher (P<0.05) concentrations in PBP and PBP-PEG treatments than in AH. However, no differences were detected in the concentrations of short, medium, and long chain fatty acids among the treatments. No differences were observed in rumen pH among the treatments, while rumen ammonia-N concentrations were lower (P<0.01) in goats fed PBP than those in the other treatments. Treatments showed no differences with regard to blood metabolites (i.e., cholesterol, triglyceride, blood urea nitrogen, total protein, albumin, and glucose). These findings indicate that the inclusion of PBP in replacement of AH in the diet of dairy Saanen goats have no adverse effects on ruminal fermentation and blood metabolites. Moreover, PBP is capable of modifying the fatty acid profile of milk in dairy goat.

ABSTRACTIn the present study, 42 multiparous Holstein cows were used to investigate the relationship between fat accumulation in the liver and dry matter intake, milk yield and blood metabolites. Based on the percentage of fat in the liver cell at 2 weeks post‐parturition, the cows were classified into three groups. These groups were: (i) less than 10% of fat (normal group, n = 29); (ii) 10–20% of fat (mild group, n = 6); and (iii) more than 20% of fat (moderate group, n = 7). The bodyweight of the moderate group was high (771 kg) before calving. The sufficiency rates of total digestible nutrients (TDN) were remarkably decreased (approximately 65%) in early lactation. The milk fat yield and milk fat composition of the moderate group were higher (P &lt; 0.05) than the other groups at 1 and 2 weeks post‐parturition. It was suggested that non‐esterified fatty acids (NEFA) mobilized from adipose tissues was directly used by the mammary gland for synthesis of milk fat. The percentage of bromsulfalein (BSP) retention of the moderate group was high (21.1%) at 30 min, and it showed that the BSP clearance function was significantly decreased. The concentrations of NEFA, β‐hydroxybutyric acid and glucose were appropriate indicators of energy status; however, aspartate aminotransferase, γ‐glutamyl transpeptidase and total bilirubin were not sensitive indicators of a moderate fatty liver. Thus, high‐yielding cows that calve in an overweight condition are more likely to develop excessive fat accumulation in the liver because of great mobilization from adipose tissues post‐parturition. In cows with a moderately fatty liver, a decrease in TDN sufficiency rates, an increase of milk fat yield and a reduction of liver function were observed in early lactation. The increase of serum NEFA and milk fat composition resulting from mobilization of adipose tissues helped to diagnose moderate fatty liver.

A negative dietary cation-anion difference (DCAD) induces a compensated metabolic acidosis, stimulating calcium (Ca) absorption and mobilization before calving, thereby decreasing clinical and subclinical hypocalcemia postpartum. The study was designed to determine the effects of varying pre- and postpartum DCAD diets on serum total calcium, ionized calcium, blood and ruminal fluid metabolites, and milk production in prepartum and postpartum Holstein cows. Fifty-four multiparous dry Holstein cows n= 54, were enrolled in a completely randomized block experimental design at 29 days prior to expected parturition through 86 days in milk. A 3 x 2 factorial arrangement of treatments was utilized. Three DCAD levels were fed precalving (0, -120 and -200 mEq/kg DM), n=18 cows per treatment and two DCAD levels were fed post calving (+200 and +400 mEq/kg DM), n=27 cows per treatment. Prepartum urine pH was lower for cows fed -200 DCAD compared with those fed -120 or 0 DCAD. Postpartum urine pH was higher for cows fed +400 mEq/kg compared to cows fed +200 mEq/kg DCAD. Prepartum serum total calcium, ionized calcium, and hydroxyproline was highest for cows fed -200 DCAD compared to those fed -120 and 0 DCAD. Parathyroid hormone was highest for cows fed 0 DCAD compared to those fed -120 and -200 DCAD. Prepartum dry matter intake (DMI) was lower for -200 and -120 DCAD compared with 0 DCAD. Postpartum DMI was not different among treatments. Pre- and postpartum DCAD treatments did not affect total milk yield or milk fat, percentage of milk protein not affected by different pre-and postpartum DCAD levels. Prepartum anionic diets lowered urine pH and parathyroid hormone and raised serum hydroxyproline, resulting in improved Ca availability after parturition. Postpartum blood metabolites were unaffected in cows given positive DCAD (+200 and +400 mEq/kg DM). Calves born to cows fed low DCAD had no change in calf bieth weight. Colostrum amount and IgG concentrations were unaffected by treatments. No effects of pre-or postpartum DCAD treatments were observed for milk yield and fat-corrected milk. Feeding prepartum an acidogenic diet improved postpartum Ca status in multiparous Holstein cows.

Effects of silage digestibility on intake and body reserves of dry cows and performance in the first part of the next lactation

Enhancing productive performance in dairy cows through supplementation of a blend of essential oils and Saccharomyces cerevisiae.

BackgroundConjugated linoleic acid (CLA) is a collective term for isomers of octadecadienoic acid with conjugated double-bond system. Thus, it was the objective to investigate whether milk composition and metabolic key parameters are affected by adding CLA to the diet of dairy cows in the first four weeks of lactation.MethodsA study was carried out with five primiparous cows fed a CLA supplemented diet compared to five primiparous cows without CLA supplementation. CLA supplemented cows received 7.5 g CLA/day (i.e. 50% cis(c)9,trans(t)11- and 50% t10,c12-CLA) starting two weeks before expected calving and 20 g CLA/day (i.e. 50% c9,t11- and 50% t10,c12-CLA) throughout day 1 to 28 of lactation.ResultsThe CLA supplement was insufficiently accepted by the animals: only 61.5% of the intended amount was ingested. Fed CLA were detectable in milk fat, whereas contents of c9,t11-CLA and t10,c12-CLA in milk fat were higher for CLA supplemented cows compared to the control group. On average over the entire treatment period, there was a decrease of saturated fatty acids (FA) in milk fat of CLA supplemented cows, combined with a higher content of monounsaturated and trans FA.Our study revealed no significant effects of c9,t11- and t10,c12-CLA supplementation either on milk yield and composition or on metabolic key parameters in blood. Furthermore the experiment did not indicate significant effects of c9,t11- and t10,c12-CLA-supplementation on gene expression of peroxisome proliferator-activated receptor-alpha (PPARα), PPARγ, sterol regulatory element-binding protein-1 and tumor necrosis factor-alpha in liver tissue.ConclusionsFeeding c9,t11- and t10,c12-CLA during the first weeks after calving did not affect metabolic key parameters of blood serum or milk composition of fresh cows. Milk fatty acid composition was changed by feeding c9,t11- and t10,c12-CLA resulting in higher contents of these isomers in milk fat. High contents of long chain FA in milk fat indicate that CLA supplementation during the first four weeks of lactation did not affect massive peripheral lipomobilization.

Concentrate allowance and corn grain processing influence milk production, body reserves, milk fatty acid profile, and blood metabolites of dairy cows in the early postpartum period

Simple SummaryThis project investigated the effects of alkyl polyglycoside (APG), a non-ionic surfactant, on lactation performance, blood metabolites and nutrient digestibility of lactating dairy cows, and found that the addition of APG at doses up to 22 mL/kg of pelleted concentrate (around 9 mL/kg of diet or 100 mL/day/head) had positive effects on milk quality in dairy cows.This study evaluated the effects of alkyl polyglycoside (APG), which is a non-ionic surfactant, on lactation performance, nutrient digestibility and blood metabolites in dairy cows. Twenty dairy cows were randomly divided into four groups and fed a basal diet that included pelleted concentrate, distillers grains, and fresh limpograss. The four treatments included 0, 5.5, 11 and 22 mL APG per kg of pelleted concentrate on a dry matter basis; treatments were defined as APG0, APG5.5, APG11, and APG22, respectively. Dry matter intake was not affected by APG supplementation. There was an increase in milk yield (from 13.96 to 16.71 kg/day) and increases in milk fat (quadratic, p = 0.04), protein (quadratic, p = 0.10), and lactose concentrations (linear, p = 0.07) with increasing APG supplementation. In addition, APG supplementation increased (p ≤ 0.03) the milk fat, protein, solid non-fat, and total solid yields, while the lactose yield increased (linear, p = 0.01) as the APG level increased. Dietary APG supplementation had no effect on nutrient digestibility and blood metabolites. It was concluded that the addition of APG at doses up to 22 mL/kg of pelleted concentrate had positive effects on the milk composition in dairy cows.

Liver cirrhosis is the pathologic end stage of chronic liver disease. Increasing evidence suggests that gut flora is implicated in the pathogenesis of liver cirrhosis complications. The aim of this study was to characterize the fecal microbial community in patients with liver cirrhosis in comparison with healthy individuals. We recruited 36 patients with liver cirrhosis and 24 healthy controls. The fecal microbial communities was analyzed by way of 454 pyrosequencing of the 16S ribosomal RNA V3 region followed by real-time quantitative polymerase chain reaction. Community-wide changes of fecal microbiota in liver cirrhosis were observed compared with healthy controls. The proportion of phylum Bacteroidetes was significantly reduced (P=0.008), whereas Proteobacteria and Fusobacteria were highly enriched in the cirrhosis group (P=0.001 and 0.002, respectively). Enterobacteriaceae (P=0.001), Veillonellaceae (P=0.046), and Streptococcaceae (P=0.001) were prevalent in patients with cirrhosis at the family level. A positive correlation was observed between Child-Turcotte-Pugh (CTP) score and Streptococcaceae (R=0.386, P=0.02). Lachnospiraceae decreased significantly in patients with cirrhosis (P=0.004) and correlated negatively with CTP score (R=-0.49, P=0.002). Using partial least square discriminate analysis, we identified 149 operational taxonomic units (OTUs) as key phylotypes that responded to cirrhosis, most of which were Lachnospiraceae (65 OTUs), Streptococcaceae (23 OTUs), and Veillonellaceae (21 OTUs). Fecal microbial communities are distinct in patients with cirrhosis compared with healthy individuals. The prevalence of potentially pathogenic bacteria, such as Enterobacteriaceae and Streptococcaceae, with the reduction of beneficial populations such as Lachnospiraceae in patients with cirrhosis may affect prognosis.

Effects of a root extract from Achyranthes Japonica Nakai on the growth performance, blood profile, fecal microbial community, fecal gas emission, and meat quality of finishing pigs