Maternal undernutrition programs fetal energy homeostasis and increases the risk of metabolic disorders later in life. This study aimed to identify the signs of hepatic metabolic programming in utero and during the juvenile phase after intrauterine undernutrition during midgestation. Fifty-three pregnant goats were assigned to the control (100% of the maintenance requirement) or restricted (60% of the maintenance requirement from day 45 to day 100 of midgestation and realimentation thereafter) group to compare hepatic energy metabolism in the fetuses (day 100 of gestation) and kids (postnatal day 90). Undernutrition increased the glucagon concentration and hepatic hexokinase activity, decreased the body weight, liver weight and hepatic expression of G6PC, G6PD, and PGC1α mRNAs, and tended to decrease the hepatic glycogen content and ACOX1 mRNA level in the dams. Maternal undernutrition decreased the growth hormone (GH) and triglyceride concentrations, tended to decrease the body weight and hepatic hexokinase activity, increased the hepatic PCK1, PCK2 and PRKAA2 mRNAs levels and glucose-6-phosphatase activity, and tended to increase the hepatic PRKAB1 and CPT1α mRNAs levels in the male fetuses. In the restricted female fetuses, the hepatic hexokinase activity and G6PC mRNA level tended to be increased, but PKB1 mRNA expression was decreased and the ACACA, CPT1α, NR1H3 and STK11 mRNA levels tended to be decreased. Maternal undernutrition changed the hepatic metabolic profile and affected the metabolic pathway involved in amino acid, glycerophospholipid, bile acid, purine, and saccharide metabolism in the fetuses, but not the kids. Additionally, maternal undernutrition increased the concentrations of GH and cortisol, elevated the hepatic glucose-6-phosphate dehydrogenase activity, and tended to decrease the hepatic glycogen content in the male kids. No alterations in these variables were observed in the female kids. Maternal undernutrition affects the metabolic status in a sex- and stage-specific manner by changing the metabolic profile, expression of genes involved in glucose homeostasis and enzyme activities in the liver of the fetuses. The changes in the hormone levels in the male fetuses and kids, but not the female offspring, represent a potential sign of metabolic programming.

This study was conducted to examine the influences of replacing soybean meal (SBM) with fermented soybean meal (FSBM) in the diet of lactating Holstein cattle on rumen fermentation and ruminal bacterial microbiome. Twenty-four lactating Chinese Holstein dairy cattle were assigned to each of the two treatments in a completely randomized design: the SBM group [the basal total mixed ration (TMR) diet containing 5.77% SBM] and the FSBM group (the experimental TMR diet containing 5.55% FSBM). This trial lasted for 54 days (14 days for adjustment and 40 days for data and sample collection), and samples of rumen liquid were collected on 34 d and 54 d, respectively. The results showed that replacing SBM with FSBM significantly increased the molar percentages of propionate (P < 0.01) and valerate (P < 0.05), but reduced the total volatile fatty acid (TVFA) concentration (P < 0.05), butyrate molar proportion (P < 0.05), and the acetate to propionate ratio (P < 0.01). The copy numbers of total bacteria (P < 0.05), Fibrobacter succinogenes (P < 0.01), Selenomonas ruminantium (P < 0.01), and Prevotella spp. (P < 0.05) in the FSBM group were greater, while the density of Prevotella ruminicola (P < 0.05) was lower than those in the SBM treatment. Additionally, Succiniclasticum ruminis and Saccharofermentans acetigenes were significantly enriched (P < 0.05) in the rumen fluid of FSBM-fed cows, despite the fact that there was no remarkable difference in the Alpha diversity indexes, structure and KEGG pathway abundances of the bacterial community across the two treatments. It could hence be concluded that the substitution of FSBM for SBM modulated rumen fermentation and rumen bacterial microbiota in lactating Holstein dairy cows. Further research is required to elucidate the relevant mechanisms of FSBM, and provide more insights into the application of FSBM in dairy cattle.

The objective of this study was to investigate the effects of partial substitution of corn silage (CS) with sweet sorghum silage (SS) in the diets of lactating dairy cows on dry matter (DM) intake, milk yield and composition, blood biochemistry, and ruminal fermentation and microbial community. Thirty mid-lactation Holstein dairy cows [mean ± standard deviation; 639 ± 42.0 kg of body weight; 112 ± 24.0 d in milk (DIM)] were assigned to 3 groups (n = 10/treatment) by considering parity, milk yield, and DIM. The cows were fed ad libitum total mixed rations containing 55% forage and 45% concentrate, with only the proportion of CS and SS varying in 3 treatments (DM basis): SS0 (0% substitution of CS), 40% CS and 0% SS; SS25 (25% substitution of CS)_, 30% CS and 10% SS; and SS50 (50% substitution of CS)_, 20% CS and 20% SS. Dry matter intake and milk protein concentration tended to linearly decrease with increasing proportion of SS in the diet. Yields of milk (mean ± standard deviation, 30.9 ± 1.12 kg/d), 4% fat-corrected milk (30.0 ± 0.81 kg/d), energy-corrected milk, milk protein, lactose, and total solids, concentrations of milk fat, lactose, somatic cell counts, and milk efficiency did not differ among diets. The concentrations in blood of urea nitrogen, phosphorus, aspartate aminotransferase, and malondialdehyde linearly increased with increasing SS proportion. Blood IgA decreased with increasing SS substitution rate, but blood IgG and IgM were not different among diets. Ruminal pH did not differ among diets, whereas ruminal NH₃-N concentration quadratically changed such that it was greater for SS50 than for SS0 and SS25. Molar proportions of propionate and acetate to propionate ratio were less for SS25 than for SS0. Although the diversity and general ruminal microbial community structure were not altered by partially replacing CS with SS, the relative abundances of predominant bacteria were affected by diets at the phylum and genus levels. Firmicutes and Bacteroidetes were dominant phyla in the ruminal bacterial community for all diets, and their relative abundance linearly decreased and increased, respectively, with increasing SS substitution rate. Prevotella_1 and Ruminococcaceae_NK4A214_group were detected as the most and the second most abundant genera, with their relative abundance linearly increased and decreased, respectively, with increasing SS substitution rate. The relative abundance of Fibrobacter linearly increased with increasing dietary SS proportion, with greater abundance observed for SS25 and SS50 than for SS0. These results suggest that substitution of CS with SS altered the relative abundances of some predominant bacteria; however, these changes had little effect on ruminal fermentation and milk yield. Under the current experimental conditions, substituting up to 50% of CS with SS had no negative effects on milk yield, indicating that SS can partially replace CS in the diets of high-producing lactating dairy cows without adding extra grain, when diets are fed for a short time. As the effects of substituting CS with SS depend upon the chemical composition and digestibility of these silages and the nutrient requirements of the cows, additional grain may be required in some cases to compensate for the lower starch content of SS.

The objective of this study was to evaluate the effects of dietary inclusion of stevioside on feed intake, feeding behavior, nutrient digestion, rumen fermentation, and serum biochemical parameters in goats. Nine male Xiangdong black goats (21.8 ± 1.5 kg of body weight) were used in a replicated 3 × 3 Latin square. All goats were fed a basal diet including concentrate and forage (chopped rice straw). The three treatments were 0, 400, or 800 mg stevioside per kg chopped rice straw on a dry matter (DM) basis. Dry matter intake of forage and total diet linearly increased (p = 0.03 and p = 0.04) with increasing stevioside in the diet. There was no effect (p > 0.05) of stevioside inclusion in the diets on eating time, rumination time, or total mastication time for the goats. Total volatile fatty acid (VFA) concentration in the rumen responded quadratically (p < 0.01), decreasing from 0 to 400 mg/kg stevioside inclusion and increasing thereafter. The inclusion of steviosid in the diets promoted a quadratic increase in the apparent total tract digestibilities of neutral detergent fiber (NDF) (p = 0.02) and acid detergent fiber (ADF) (p = 0.01). Based on the results of this experiment, it could be concluded that supplementing goat diets with stevioside at 400 mg/kg to 800 mg/kg forage (about 270 to 541 mg/kg diet) resulted in increased dry intake of forage and total diet, suggesting that stevioside has positive potential as a feed additive to improve feed intake.

This study examined the effects of a high-dose Saccharomyces cerevisiae inoculant alone or jointly with Lactobacillus plantarum on nutrient preservation, fermentation quality, and aerobic stability of sweet corn stalk silage. Fresh stalks (231 g dry matter (DM)/kg) were chopped and subjected to the following treatments: (1) deionized water (Uninoculated; U); (2) S. cerevisiae at 1 × 10⁸ cfu/g of fresh forage (S); and (3) S. cerevisiae at 1 × 10⁸ cfu/g plus L. plantarum at 1 × 10⁵ cfu/g (SL). Treated stalks were ensiled in 5-litre laboratory silos for 30, 60, and 90 day. The S and SL silages had a greater (p < 0.001) pH and greater crude protein, ammonia nitrogen/total nitrogen, neutral detergent fibre, acid detergent fibre, and ethanol contents at all three ensiling periods than the U silage. Acetate, propionate and volatile fatty acids in the S and SL silages after 30 and 90 day of ensiling were greater (p < 0.05) than those in the U silage, but they were lower (p < 0.05) in the S and SL silages than in the U silage after 60 day. The lactate and V-score of the S and SL silages were lower (p < 0.001) than those of the U silage at all three ensiling periods. Compared with the U group, the aerobic stability of the S silage after 90 day of ensiling decreased (p < 0.05), and the aerobic stability of the SL silage was unaffected (p > 0.05). Overall, the quality of sweet corn stalk silage was not improved by inoculation with 10⁸ cfu/g of S. cerevisiae alone or in combination with 1 × 10⁵ cfu/g of L. plantarum.

The purpose of this study was to investigate the effects of dietary L-theanine supplementation on apparent nutrient digestibility, milk yield, milk composition, and blood biochemical indices of dairy cows under heat stress. Thirty Chinese Holstein cows (19.84 ± 2.42 kg milk/d, 192.36 ± 40.77 d in milk and 2 ± 0.93 parities) were divided into 3 groups of 10 animals each. The control group was fed a basal total mixed ration (TMR) diet, while treatment 1 (LTA16) and treatment 2 (LTA32) groups were fed a basal TMR diet supplemented with L-theanine at 16 and 32 g/cow per day, respectively. The results showed that feeding the dairy cows with LTA16 treatment decreased (P < 0.05) their rectal temperature, whereas feeding with LTA32 treatment decreased (P < 0.05) their rumen fluid ammonia nitrogen content. In comparison to the control group, the supplementation of L-theanine had no significant effect (P > 0.05) on the dry matter intake, nutrient digestibility, total volatile fatty acid (TVFA) concentration and molar proportion of volatile fatty acid, milk yield, milk composition, feed efficiency and antioxidant capacity of the dairy cows. The triglyceride (TG) content of the LTA32 group was significantly greater (P = 0.014) than that of the control group. With the increase in L-theanine dosage, the serum cholesterol (CHOL) content significantly increased (P = 0.013). The serum albumin (ALB; P = 0.067), low-density lipoprotein cholesterol (LDL-C; P = 0.053), and high-density lipoprotein cholesterol (HDL-C; P = 0.067) contents showed an upward trend as L-theanine dosage increased. Ultimately, the results of this study show that supplementing dairy cow diet with L-theanine could decrease dairy cow rectal temperature, affect lipid metabolism, and potentially relieve the heat stress of dairy cows to some extent.