Animal Feed Science and Technology最新文献

In late pregnancy and early lactation, ewe^'s demand increases for zinc (Zn), and selenium (Se) for scavenging of free radicals and due to transfer via placenta, colostrum or milk to lamb.This experiment was conducted to study the effect of slow-release bolus of Zn and Se on performance, and some blood parameters of pregnant ewes in the last third of pregnancy, and early lactation as well as their lambs. Twenty-one ewes were estrus synchronized in the breeding season by intra vaginal insertion of sponge containing medroxyprogesterone acetate. Forty-five days before the expected date of parturition, the pregnant ewes (3–4 years old and 55±5.2 kg in weight) were randomly assigned to one of the three groups: 1) control, 2) slow-release glass bolus with mean release of 20 mg Zn and 0.2 mg Se per day (Bolus), and 3) 20 mg Zn and 0.2 mg Se per day as sulfate and selenite, respectively via Daily feeding (Daily). Blood samples were obtained from ewes at 105th and 135th days of pregnancy, at parturition and 15th day postpartum and from lambs at 15 days of age. The results indicated that total feed intake of ewes increased (P = 0.03) in the Bolus and Daily groups than control. Supplementation of Zn and Se in both methodssignificantly increased Total Antioxidant Capacity (TAC) in the ewesand their lambs than the control group. Compared with the control, there was higher triiodothyronine (T₃) in ewes and their lambs and lower tetraiodothyronine (T₄) only in lambs in Bolus and Dailygroups. Increased T₃ to T₄ ratio in ewes (at days 135 of pregnancy and at parturition) and their lambs was recorded in Bolus and Daily than the control group. An increased level of alkalinephosphatase (ALP) in ewes was observed in the Bolus and Daily groups compared with the control. Alanine amino transferase (ALT) activity on day 135 of pregnancy was significantly reduced by Zn and Se supplementation in both methods. Bolus and Daily groups of ewes had lower creatinephosphokinase (CPK), and their lambs had lower aspartate amino transferase (AST), ALT, CPK, and gamma-glutamyltransferase (GGT) than the control group. Regardless of the supplementation method, Zn and Se increased glucose (P = 0.02) and decreased triglyceride (P = 0.06) in ewes. In the ewes supplemented with Zn and Se, creatinine concentration significantly decreased in parturition day compared to control. Total protein, albumin, globulin and ratio of albumin to globulin in ewes and their lambs were not different between treatments. As a result, Zn and Se improved antioxidant status and some blood parameters in ewes and their lambs. Efficacy of slow-release bolus of Zn and Se was similar with daily feeding of these elements.

Plant protein sources are the main alternative to fish meal (FM), but excessive substitution can induce inflammatory responses and oxidative stress in aquatic animals. In this study, the antioxidant capacity, endoplasmic reticulum stress (ERS), apoptosis and intestinal health of Litopenaeus vannamei at the different stages of feeding trial were evaluated after replacing FM with soy protein concentrate (SPC). Two diets were designed: HF diet (25% FM) and LF diet (15% FM + 10% soy protein concentrate), respectively. The samples were collected at 7d, 14d, 28d, 42d, 56d of the feeding trial. The results showed that the antioxidant capacity of the hepatopancreas of shrimp fed the LF diet gradually decreased after 28d. The glutathione peroxidase (GSH-PX) activity, superoxide dismutase (T-SOD) activity and total antioxidant capacity (T-AOC) showed a decreasing trend with the went on of the feeding trial and were lower than those of shrimp fed a HF diet. The length of microvilli and height of mucosal folds in shrimp fed the LF diet were significantly lower than those fed the HF diet after 42d (P<0.05), and the endoplasmic reticulum and mitochondria were swollen, and the mitochondrial matrix showed irregular structure and even almost complete dissolution at 56d. The expression of hepatopancreatic endoplasmic reticulum stress (ERS)-related genes was highest at 14d, and the hepatopancreatic endoplasmic reticulum-related genes were overall higher in shrimp fed the LF diet than those fed the HF diet after 28d. The expression of apoptosis-associated genes in hepatopancreatic cells showed an overall decreasing trend. However, the relative expression of intestinal ERS and apoptosis related gene was in the opposite trend. ERS was enhanced and apoptosis was inhibited in shrimp since 7d of the feeding trial when the dietary FM level was reduced. In conclusion, the antioxidant capacity and immune response of shrimp would be reduced as the feeding trial went on, ERS and apoptosis in the intestine of shrimp fed a LF diet would be earlier to be induced compared to those fed the HF diet.

AMP-activated protein kinase-alpha 1 (AMPKα1) plays a vital role in glucose and lipid metabolism. Five isonitrogenous and isolipid diets with starch levels (15%, 20%, 25%, 30% and 35%) were formulated to study the modulation of AMPKα1 in hepatic lipid deposition induced by high gelatinized starch diet in rice field eel (Monopterus albus) (initial body weight, 30.00 ± 0.10 g) and the growth trial lasted for 8 weeks. The results showed that dietary gelatinized starch did not affect the growth performance of rice filed eel compared with S15 group. High gelatinized starch could induce AMPKα1 expression and glucose catabolism, and inhibit hepatic glycogen synthesis without effecting glucose content. Dietary ≥ 30% gelatinized starch began to dramatically suppress gluconeogenesis and promote the lipid synthesis, followed by a higher triglyceride (TG) and hepatic crude lipid. Dietary 20–30% gelatinized starch induced phosphorylation of AMPKα compared to 15% gelatinized starch diet, whereas 35% starch dramatically suppressed AMPKα phosphorylation together with unnormal increase in phosphorylation of forkhead box O1 A (FOXO1A) and acetyl-CoA carboxylase (ACC), TG content compared to 30% starch. In short, high gelatinized starch could induce AMPKα1 expression and promoted systemic metabolism, whereas dietary ≥ 25% gelatinized starch initially suppressed AMPKα1 activation and caused abnormal lipid deposition in liver of rice field eel.

A 56-days nutritional trial was conducted to examine the influence of including a corn-oil based diet with lysolecithin (LL) on stellate sturgeon (Acipenser stellatus) juveniles. Fish were fed four experimental diets (44% crude protein, 15% crude lipid) containing graded levels of LL [0 (control), 0.5, 1 and 2%)]. One hundred and eighty juvenile fish (45.3 ± 0.1 g, mean ± standard deviation) were stocked in twelve 300 L-polyethylene tanks containing ground water at 18.9 ± 0.5°C. Feeds were offered to fish at apparent satiation four times daily. Fish fed 1% LL-supplemented diet had higher growth and better feed conversion ratio than the control group (P < 0.05). The amounts of protein and lipid levels in the whole body increased in fish fed LL-supplemented diets compared to control, whereas the levels of n-6 PUFA, particularly linoleic acid, increased in fish fed 0.5 and 1% LL-supplemented diets. Total long chain polyunsaturated fatty acids increased in fish fed 1% LL-supplemented diet. Regarding digestive enzymes, trypsin (alkaline pancreatic proteases) and pepsin (acid gastric protease) activities decreased with increasing LL in the diet. Overall, these results indicated that 1% LL is recommended for better growth performance of stellate sturgeon juveniles.

Eichhornia crassipes leaf meal (ELM) was fermented by solid-state fermentation using Chaetomium globosum MTCC 4179 that resulted in considerable changes in its nutrients and anti-nutrient profile. Both fermented ELM (FELM) and raw ELM were evaluated in the feed of Cyprinus carpio fingerlings through a feeding trial of 56 days. Five iso-nitrogenous and iso-caloric diets viz. C, Control (30% DORB and 0% ELM or FELM), ELM15 (15% ELM with replacement of 50% DORB), ELM30 (30% ELM with replacement of 100% DORB), FELM15 (15% FELM with replacement of 50% DORB), and FELM30 (30% FELM with replacement of 100% DORB) were prepared and fed on satiation basis to 180 acclimated fish (body weight 8.38–8.48 g) of five respective groups in triplicate with the stocking density of 12 fish /tank. Significantly (P<0.05) higher weight gain (%), specific growth rate, and protein efficiency ratio and lower feed conversion ratio (FCR) were observed in ELM15 and FELM15 groups compared to the control. However, the growth performance of ELM30 and FELM30 groups showed no significant (P>0.05) difference with control group. Furthermore, fermented diets (FELM15 and FELM30) could not improve the growth performance of fish as compared to their non-fermented counterparts (ELM15 and ELM30). Total red blood cell count, packed cell volume (%), and total serum protein (g/dl) were significantly (P<0.05) higher in ELM15 compared to other ELM and FELM-based groups. Better body composition was observed in fish of ELM15 group, however, fish of control, and ELM30 showed similar body protein, lipid, ash and total carbohydrate. Thus, it is concluded that raw ELM can be incorporated in the diet of common carp up to the level of 30% with complete replacement of DORB without compromising the growth performance of fish. However, the fermentation of ELM with Chaetomium could not impart any additional benefits in terms of growth performance of fish. In addition, dietary inclusion of 15% raw or fermented ELM, in replacement of 50% DORB, can result in higher growth performance with better health condition of common carp fingerlings.

It is well known that allicin has anti-bacterial, anti-oxidation, and anti-inflammatory biological functions. However, there is little information on whether allicin has beneficial effects on ruminants fed a high-grain (HG) diet. This study was conducted to investigate the effects of allicin addition on growth performance, ruminal microbes in different rumen ecological niches (REN), and the rumen epithelial (RE) proteome in fattening goats fed a HG diet. Twenty-four Anhui white goats were randomly allocated to three dietary treatments: control diet (CON, n = 8), high-grain diet (HG, n = 8), and high-grain diet + allicin (HGA, n = 8). After 56 days, blood, rumen fluid (RL), rumen solid (RS), and RE tissue were sampled for further analysis. Compared with the HG diet, the addition of allicin decreased (P < 0.05) the DMI, with no effects (P > 0.05) on daily weight gain and rumen fermentation parameters. The malondialdehyde concentrations were lower (P < 0.05) in the HGA group than in the HG group. The HGA group had a higher activity of glutathione peroxidase in the rumen epithelium than the HG group. The alpha diversity in different REN in the HGA group was higher (P < 0.05) than that in the HG group. Compared to the HG group, the HGA group had higher relative abundances of Lachnospiracea_incertae_sedis, Ruminobacter, and Bifidobacterium (P < 0.05), and lower relative abundances of Methanomassiliicoccus (P < 0.05). The addition of allicin helped mitigate or reverse the differences between the HG diet and the CON diet at the genus level in different RENs. Proteomic analysis of the rumen epithelium showed that proteins involved in cell junction and immune function were downregulated, whereas those involved in oxidative stress and inflammatory reactions were upregulated in the HG group in comparison with the CON group. Compared with the HG group, the addition of allicin increases the abundance of proteins involved in cell junction and immune function and decreases those of proteins involved in oxidative stress and inflammatory reactions. Our findings indicate that the addition of allicin can improve the antioxidant capacity, modify the rumen microbial composition, alleviate the damage to the rumen epithelium cell junction, and protect the rumen epithelium of goats fed a HG diet.

This study examined the impact of supplementing Bacillus spp. mixtures at concentrations of 0.2 g/kg (PRO-0.2) and 0.5 g/kg (PRO-0.5) on Nile tilapia (Oreochromis niloticus) for 90 days. Fish groups receiving PRO-0.2 and PRO-0.5 exhibited significantly lower water ammonia levels than the control group, in linear and quadratic patterns. Furthermore, their length and weight increased exponentially over time, peaking at the end of the experiment. After 90 days, the PRO-0.5 group displayed the highest mean weight gain. Additionally, both the PRO-0.2 and PRO-0.5 groups had the lowest food conversion ratios and highest protein efficiency ratios in a linear pattern. They also showed improved liver function, as indicated by lower levels of liver enzyme (aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase) compared to the control group. In terms of the lipid profile, the PRO-0.2 and PRO-0.5 groups had significantly lower serum levels of low-density lipoprotein, triglycerides, in linear and quadratic patterns, and cholesterol compared to the control group, with no significant differences in cholesterol levels. High-density lipoprotein increased significantly in both PRO-0.2 and PRO-0.5 groups after 90 days, following a linear pattern. Hepatic alkaline phosphatase levels decreased in both the PRO-0.2 and PRO-0.5 groups, following a significant linear pattern over time. After 30 days, the expression of hepatic fatty acid binding protein 3 (fabp3) significantly decreased in the PRO-0.5 group. Intestinal cluster of differentiation 36 (cd36) and fabp3 expression markedly increased, with cd36 showing the greatest rise. After 90 days, hepatic cd36 expression became prominent in both PRO-0.2 and PRO-0.5 groups. Expression of fas was significantly downregulated in both the PRO-0.2 and PRO-0.5 groups. Notably, hepatic lipoprotein lipase (lpl) expression significantly increased in the supplementation groups after 30 days but decreased significantly after 90 days. Overall, this study highlights the positive impact of dietary mixtures of Bacillus spp. on various aspects, including water quality, growth performance, feed utilization, survivability, expression of lipid metabolism-related genes, lipid profile, body composition, and bacterial load in both water and fish bodies.

The toxic sporophyte marsh horsetail (Equisetum palustre L.) increasingly infests moist and wet grasslands in Europe because of climate change, deeutrophication actions, and rewetting measures. Farmers, veterinarians, and authorities are insecure how to address this newly emerging situation, as only little information on toxin levels is available and information for no effect levels in livestock is based on outdated analytical methods. Hence, an important question is to what extent feed conservation measures could lead to a significant reduction in alkaloid levels. We investigated the capabilities of the two most common forage conservation methods, haying and ensiling, in reducing the initial alkaloid levels of fresh E. palustre contaminated biomass by field and lab-scale experiments simulating favourable and no favourable conservation conditions. Haying reduced the main alkaloid content up to 25% under ideal drying conditions only, probably due to friability losses of horsetail plant parts. However, under non-favourable weather conditions, alkaloid concentrations increased. Ensiling procedures reduced the main alkaloid content by less than 10%. There were no significant effects of ensilage duration or wilting degree on alkaloid content, despite a tendency toward a higher reduction in fresh silages. Common forage conservation methods have limited potential for degradation of the main marsh horsetail alkaloids. Our results give reason to consider other biomass utilization paths, such as composting or biomethanization for contaminated grassland growth instead of classical feed preparation.

Asparagopsis armata steeped in edible oil (Asp-Oil) to stabilise its primary antimethanogenic compound, bromoform, has emerged as a potent enteric methane mitigant for ruminant livestock. The aim of this 41-day study was to evaluate the response of feeding a range of effective inclusion levels of a canola oil based Asp-Oil providing increasing dietary concentrations of bromoform to lactating dairy cows in a supplemental feed concentrate twice daily at milking on i) enteric methane emissions, milk yield (MY) and dry matter intake (DMI), and ii) bromoform, dibromomethane or bromine concentrations in milk, urine, faeces, blood and breath. Thirty lactating, multiparous, Holstein-Friesian (42 ± 12.9 days in milk) were randomly allocated to one of five treatments; ASP0 (0 mg bromoform/d), ASP1 (132 mg bromoform/d), ASP2 (267 mg bromoform/d), ASP3 (409 mg bromoform/d) and ASP4 (467 mg bromoform/d). The Asp-Oils were mixed with the concentrate supplement and offered twice daily during milking and all cows received equal dietary canola oil. The basal diet consisted of vetch hay ad libitum and intakes were measured daily via electronic monitoring of individual cows at the feed bins. Methane emissions were measured using the modified sulphur hexafluoride (SF₆) tracer technique on days 36–41. Feeding Asp-Oil showed no effect on total DMI but concentrate DMI and MY decreased linearly with increased concentration of bromoform in the Asp-Oil. There was a linear decrease in methane production (MeP; g CH₄/d), methane yield (MeY; g CH₄/kg DMI) and methane intensity (MeI; g CH₄/kg energy corrected milk) with increased bromoform concentration in the Asp-Oil. Milk bromoform was detected in each of the Asp-Oil treatment groups, however accounted for less than 0.07% of total bromoform intake and is more than 14 times less than the acceptable daily intake limits for human consumption. It is concluded that feeding lactating dairy cows a concentrate including Asp-Oil with increasing concentrations of bromoform showed a linear response on methane emissions with reductions of up to 38% in MeP.

In tropical or subtropical areas, high temperatures and prolonged storage time usually result in poor fermentation quality, poor aerobic stability and dry matter loss of silages. This study explored the effect of heat-resistant Lactobacillus buchneri TSy1–3 (LB), Lactobacillus rhamnosus BDy3–10 (LR), and their combination (M) on the nutritional characteristics, fermentation parameters and microbiota of whole plant maize silage during long-duration ensiling in the subtropical area. The results showed that long-term ensiling naturally led to a decrease in water-soluble carbohydrate, neutral detergent fiber and acid detergent fiber concentrations. In contrast to the control treatment, LB, LR and M reduced the coliform bacteria population and the nutrient loss, while increased lactic acid bacteria population and acetic acid and propionic acid concentrations after 180 d of fermentation. Moreover, they helped to increase Lactobacillus abundance and made it still dominate the bacterial community during long-term storage. The negative/positive ratio was higher in the LR and LB treatments when compared with the control treatment, suggesting that LR and LB increased the stability of the bacterial community networks. The heat-resistant inoculants rapidly produced lactic acid to modulate the bacterial community composition during 60 d of ensiling, while generated more acetic acid and propionic acid to alter the microflora during 180 d of ensiling. This may be caused by predicted functions indicating that metabolism pathways were modulated by different inoculations and storage times. Overall, heat-resistant lactic acid bacteria improved the nutritional and fermentation quality of ensiled forage and regulated the bacterial community during long-term storage in the subtropical region.