Effects of the Partial Replacement of Soybean Meal by Insect or Algae Meal in Chicken Diets with Graded Amino Acid Supply on Parameters of Gut Microbiology and Dietary Protein Quality

Insects or algae are considered future solutions to substitute imported feed proteins like soybean meal (SBM) in animal nutrition. The objective of this research, as part of the multidisciplinary project “Sustainability transitions”, focused on replacing 50% SBM by partly defatted larvae meal from black soldier flies (Hermetia illucens) or the blue-green algae Spirulina platensis in meat type chicken diets. The current study aimed to evaluate the effects on body composition, protein quality, apparent precaecal digestibility (apcD) and parameters of intestinal microbiota. In total, 288 one-day-old male growing chickens (Ross 308) from a commercial hatchery were randomly allotted to 48 pens (6 birds per pen) across five diets, which were fed at a free choice level. The control diet utilized SBM, wheat and corn as main ingredients, and experimental diets replaced 50% of SBM by the alternative proteins under study. Amino acid (AA) supplementation of the final diets was conducted both at a basic level (diets HM, SM;Lys and Met added equal to the control diet) and an extended level of AA fortification (diets HM+, SM+;extended supplementation of Lys, Met, Thr, Arg). After finishing the growth study, 4 individual birds per diet were slaughtered for whole body analyses to derive nutrient utilization and dietary protein quality parameters. Additionally, pooled chyme samples from 16 birds per diet (control, HM and SM) were analyzed to assess apcD and microbial parameters. Diets HM and SM with a basic level of AA fortification led to significant depressions in nutrient deposition and dietary protein quality. However, HM+ and SM+ diets with an extended level of AA supplementation led to significantly improved responses;however these were still generally not on par with the control diet. The HM+ diet provided superior CP deposition and dietary protein quality, as compared to the SM+ diet, but equal to the control diet. Results of gut microbiology yielded no significant effects due to feeding the alternative protein sources under study.

Effect of New Fly Maggot Protein Feed on mRNA Expression of TOR Signaling Pathway-related Genes in Loaches (Misgurnus anguillicaudatus)

[Objectives] This study was conducted to explore the effects of new fly maggot protein feed on the mRNA expression of genes related to the TOR signaling pathway in loaches(Misgurnus anguillicaudatus). [Methods] Two kinds of test feed with equal nitrogen and energy were prepared by replacing 60% of the fish meal in the control group with the new fly maggot protein feed, i.e., Diet1(control group) and Diet2(60% fish meal replacement group). The feeding experiment was carried out in an indoor circulating water system, and the breeding period was 60 d. [Results] For the livers, the mRNA levels of TOR and 4EBP1 in the Diet2 group were significantly higher than those in the Diet1 group(P<0.05), while the expression of 4 EBP2 was lower than in the Diet1 group(P<0.05);and as to the muscles, the mRNA levels of TOR and 4EBP1 in the Diet2 group were significantly lower than those in the Diet1 group(P<0.05), while there was no significant change in the mRNA level of 4EBP2 between the two groups. [Conclusions] The replacement of fish meal by fly maggot cultures affected the mRNA expression of TOR, 4EBP1 and 4EBP2 in loach livers and muscles.

Functions of Mulberry in the Development of Ecological Animal Husbandry and Development Ideas

Ecological animal husbandry is an animal husbandry industry system integrating ecological benefit, economic benefit and social benefit. Breeding cycle is one of the main patterns of ecological animal husbandry development, but breeding cycle does not form a relatively closed cycle of endogenous resources. In recent years, forage value and ecological value of mulberry have made some progresses in different research areas and angles, but the thought and practice of both forage and ecological value of mulberry has not been systematically interpreted and researched. Based on the short board of animal husbandry development and the advan- tage of mulberry, animal husbandry and mulberry were complemented and fused, and relatively closed planting and raising ecological recycling pattern with mulberry as the axis was raised. Phased scientific research and production test data were obtained, and the problems and development suggestions were put forward in the following aspects ： selection of mulberry varieties with both forage and ecological value, cost control of mulberry with both forage and ecological value, quality and safety control system of forage mulberry, orientation of feeding value of forage mulberry.

Evaluation of nutritive value and in vitro rumen fermentation gas accumulation of de-oiled algal residues

Background：Algae are widely recognized for their high oil content and for exponentially accumulating biomass with particular potential to provide single cell protein for human consumption or animal feed.It is believed that along with biodiesel from algae,the high protein de-oiled algal residue may become an alternative feed supplement option in the future.This study was conducted to investigate de-oiled algal residue obtained from the common Chlorella species,Thalassiosira weissflogii,Selenarstrum capricornutum,Scenedesmus sp.,and Scenedesmus dimorphus for assessment as potential feed supplements for ruminants by comparing with soybean（Glycine max） meal and alfalfa（Medicago sativa） hay.Results：With the exception of T.weissflogii,algal residue had higher concentrations of Cu,Zn,and Mn and lower concentration of Ca,Mg,and K than soybean meal and alfalfa hay.The algal residue CP（crude protein）concentrations ranged from 140 to 445 g/kg DM and varied among the de-oiled residues.In vitro rumen fermentation gas accumulation curves indicated that algal biomass degradation potential was less than that of soybean meal or alfalfa hay by up to 41.7%.The gas production curve,interpreted with a dual pool logistic model,confirmed that the fraction sizes for fast fermenting and slow fermenting of de-oiled algal residues were smaller than those in soybean meal and alfalfa hay,and the fermenting rate of the fractions was also low.Conclusions：Inferior in vitro rumen gas accumulation from the five de-oiled algal residues suggests that these algal byproducts are less degradable in the rumen.

Effects of fermented protein feed on the growth performance of pond-raised crab

This study aimed to elucidate the effect of a pellet feed containing fermented proteins on pond-raised Chinese mitten crabs,Eriocheir sinensis in a 7-month crab feeding experiment in Gucheng Lake,Jiangsu province,China.The results showed that fermented protein could significantly increase mean weight gain,crab size and total yield compared with control group.Moreover,the mean weight of male crabs and the number of large-sized male crabs improved over those of the control group.However,feed efficiency ratio did not differ significantly between the two groups.The amino acid content in the muscles of the female crabs of both the groups was higher than that in the muscles of the male crabs.The present study suggests that fermented compound protein may be one kind of potential protein sources for E.sinensis.

Partial replacement of soybean meal by yellow mealworm(Tenebrio molitor)meal influences the flesh quality of Nile tilapia(Oreochromis niloticus)

This study investigated the effects of yellow mealworm meal(YM)replacing soybean meal(SBM)at different proportions(0%,15%,30%and 45%,referred as YM0,YM15,YM30 and YM45,respectively)on the flesh quality of Nile tilapia.A total of 360 fish(70.0±0.12 g)were randomly divided into 4 groups(3 tanks per group).Fish were fed the experimental diet twice daily for 10 wk.The results showed that muscle protein content significantly decreased in YM30 and YM45,while the lipid content significantly decreased in YM45(P<0.05).The essential amino acids and flavor amino acids of the muscle were not affected by the YM substitution,while saturated fatty acid content decreased in YM30 and YM45 compared with YM0(P<0.05).Fillets in YM45 had higher hardness,gumminess,and a higher proportion of thin myofibers(≤100μm,P<0.05)than those in other groups.Further analysis revealed that apoptosis and atrophy related genes were up-regulated,while the muscle antioxidant capacity decreased significantly in YM45(P<0.05),which may be related to the high acid value in YM45 diet.Our findings indicated that YM could replace up to 30%SBM without substantially altering the flesh quality.When the replacement ratio increased to 45%,the flesh quality would change.Special attention should be paid to avoid feed rancidity which may affect the flesh quality of fish.

Mechanism of action,benefits,and research gap in fermented soybean meal utilization as a high-quality protein source for livestock and poultry

Animal nutritionists have incessantly worked towards providing livestock with high-quality plant protein feed resources.Soybean meal(SBM)has been an essential and predominantly adopted vegetable protein source in livestock feeding for a long time;however,several SBM antinutrients could potentially impair the animal's performance and growth,limiting its use.Several processing methods have been employed to remove SBM antinutrients,including fermentation with fungal or bacterial microorganisms.According to the literature,fermentation,a traditional food processing method,could improve SBM's nutritional and functional properties,making it more suitable and beneficial to livestock.The current interest in health-promoting functional feed,which can enhance the growth of animals,improve their immune system,and promote physiological benefits more than conventional feed,coupled with the ban on the use of antimicrobial growth promoters,has caused a renewed interest in the use of fermented SBM(FSBM)in livestock diets.This review details the mechanism of SBM fermentation and its impacts on animal health and discusses the recent trend in the application and emerging advantages to livestock while shedding light on the research gap that needs to be critically addressed in future studies.FSBM appears to be a multifunctional high-quality plant protein source for animals.Besides removing soybean antinutrients,beneficial bioactive peptides and digestive enzymes are produced during fermentation,providing probiotics,antioxidants,and immunomodulatory effects.Critical aspects regarding FSBM feeding to animals remain uncharted,such as the duration of fermentation,the influence of feeding on digestive tissue development,choice of microbial strain,and possible environmental impact.