Body Weight Gain In Rats Research Articles

Effect of thyme, ginger, and their nano-particles on growth performance, carcass characteristics, meat quality and intestinal bacteriology of broiler chickens

This study was conducted to evaluate the effects of thyme, ginger, and their nano-particles, as alternatives to antibiotic growth promotors (AGP), on productive performance, carcass traits, meat quality and gut health of broiler chickens. A total of 270 one-day-old broiler chicks were randomly distributed into 6 groups, each consisting of 3 replicates (n = 15 chicks/replicate). The birds in group 1 were fed the control diet which contained neither antibiotic growth promotors nor phytogenic feed additives (PFA). Birds in group 2 were fed diets containing 0.05% of AGP (Bacitracin methylene disalicylate). Chicks in group 3 and 4 were fed diets supplemented with 1.0% of thyme and ginger, respectively, whereas birds in group 5 and 6 were offered diets including 0.10% of nano-thyme and nano-ginger, respectively. The experiment lasted for 35 days. It was found that thyme and ginger with their nano-products, like the antibiotic, improved the body weight, weight gain and feed conversion rate of birds. The effect of ginger and nano-ginger on body weight and weight gain was greater than other treatments. During the overall feeding period, the feed cost of production was the highest in antibiotic group, but was the lowest in ginger and nano-ginger treatments. There was no effect of dietary treatments on carcass yield or organs weight except bursa of Fabricius and abdominal fat. Thyme, ginger and their nano-composites increased the weight of bursa and reduced the abdominal fat amount. The phytogenic additives and their nano-particles improved the colour, water holding capacity, and flavor of meat. Moreover, these additives reduced the total intestinal bacterial count as well as the total aerobic mesophilic count of meat. The effect of PFA and their nano-particles on the bacterial count was similar to that of antibiotic. In conclusion, thyme and ginger with their nano- particles can be considered as promising agents in feeding of broilers to improve the growth performance, gut health and meat quality. Moreover, these additives can be used as alternatives to AGP to overcome its health hazards and the high cost. The nanotechnology of herbal plants enables them to be added in smaller amounts in poultry diets with producing the same effect of raw ingredients, and this could be due to the higher bioavailability.

Dietary Cyanus depressus (M. Bieb.) Soják plant extract enhances growth performance, modulates intestinal microbiota, and alters gene expression associated with digestion, antioxidant, stress, and immune responses in rainbow trout (Oncorhynchus mykiss)

This study aimed to assess the effects of dietary Cyanus depressus (CD) extract on rainbow trout (Oncorhynchus mykiss) physiology and health. Fish with an average weight of 3.29 ± 0.34 g were allocated to four feeding groups, receiving diets containing CD extract at doses of 0 (Control), 0.5 (CD05), 1 (CD1), and 2 (CD2) g kg−1 for a period of 60 days. Results revealed significant improvements in final body weight, weight gain, and specific growth rate in groups supplemented with 1 and 2 g/kg of CD extract. Lipase activity increased notably in fish fed with CD0.5, CD1, and CD2 diets. The CD1 group exhibited the highest trypsin activity, while the groups receiving 1 g/kg and 2 g/kg of CD extract displayed the highest amylase activity. Analysis of gene expression levels for superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) showed marked increases across all groups compared to the control, with the most significant enhancement observed in fish fed with 2 g/kg of CD extract. Significant variations were observed in the expression of immunity-related genes among the treatments, with the highest expression levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) found in groups fed a diet enriched with CD extract. The increased activity of immune-related genes was more prominent in fish fed 2 g/kg of CD extract than in the control group. Notably, in fish fed with CD extract, heat shock protein 70 (HSP70) gene expression increased in the CD2 group, decreased in the CD05 group, and remained statistically unchanged in the CD1 group compared to the control. Additionally, supplementation with CD extract altered the composition and abundance of the intestinal microbiota in rainbow trout. In conclusion, our study suggests that Cyanusdepressus extract has significant potential for enhancing various physiological and health aspects of rainbow trout, particularly when supplemented at 2 g/kg.

Susceptibility and cecal microbiota alteration to Eimeria-infection in Yellow-feathered broilers, Arbor Acres broilers and Lohmann pink layers

Coccidiosis, which is caused by Eimeria species, results in huge economic losses to the poultry industry. Arbor Acres (AA) broilers and yellow-feathered broilers are the dominant broilers in northern and southern China, respectively. However, their susceptibility to coccidiosis has not been fully compared. In this study, the susceptibility of yellow-feathered broilers, AA broilers and Lohmann pink layers to E. tenella was evaluated based on mortality rate, relative body weight gain rate, intestinal lesion score, oocyst output, anticoccidial index (ACI), and cecum weight and length. The yellow-feathered broilers were shown to produce significantly fewer oocysts with higher intestinal lesion score compared to AA broilers, which had the highest growth rates and ACI scores. Subsequently, changes in the cecal microbiota of the 3 chicken lines before and after high-dose infection (1 × 104 oocysts) with E. tenella were determined by 16S rRNA sequencing. The results showed that composition of the microbiota changed dramatically after infection. The abundance of Firmicutes and Bacteroidetes in the infected chickens decreased, and Proteobacteria increased significantly among the different chicken lines. At the genus level, Escherichia increased significantly in all 3 groups of infected chickens, but Lactobacillus decreased to 0% in the infected yellow-feathered broilers. The results of the study indicate that the susceptibility to E. tenella varies among the 3 chicken lines, and that changes in intestinal microbiota by E. tenella-infection among the different chicken lines had a similar trend, but to different degrees. This study provides basic knowledge of the susceptibility in the 3 chicken lines, which can be helpful for the control and prevention of coccidiosis.

PSV-3 Effects of maternal early gestational weight gain on multigenerational skeletal muscle gene regulation in offspring

Abstract Maternal nutrition during the periconceptional period may have multigenerational effects on the gene regulation of fetal skeletal muscle. This study aimed to investigate the impact of maternal rate of body weight gain (F0) during early gestation on the differential gene expression in the skeletal muscle of newborn (F1) and second-generation fetuses (F2) female offspring. To this end, crossbred Angus heifers (F0) were assigned to either a low gain (LG; 0.28 kg/d; n = 8) or moderate gain (MG; 0.79 kg/d; n = 8) group during the first 84 d of gestation. Subsequently, heifers (F0) were managed as a single group on a forage-based diet until the weaning of the F1 offspring (8 mo). The F1 heifers were estrus synchronized and bred via AI at 15 mo, and F2 fetuses were harvested on d 84 of gestation. Longissimus dorsi muscle was collected at birth (F1) and the 84-d harvest in F1 heifers and their F2 fetuses for multigenerational RNA-Seq analysis. Differentially expressed genes (DEGs) were identified using the DESeq2 R-package. Significant genes were retrieved based on P - value ≤ 0.05 and log2 fold change|0.5|. We previously reported that F1 heifers from MG dams at birth were ~2 kg heavier (P < 0.03), and herein we report the impact on the gene regulation of skeletal muscle in the F1 and F2 generations. At birth, F1 heifers from MG cows exhibited 275 DEGs, of which 98 were downregulated, and 177 genes were upregulated, related to the immune system (TNFAIP3, TLR5), cellular signaling and transduction (RASGRP2, NFE2), and extracellular matrix (TGM3, MMP17). Changes in gene expression persisted in F1 heifers through development, breeding, and until the evaluation at d 84 of gestation. At this time point, we identified 75 upregulated genes out of 177 DEGs. These genes were underlying cellular functions (USP43, PASK), hematopoiesis (THPO), metabolism, and enzymatic activity (SMOX, OAT) as possible metabolic adaptations. Similarly, 102 genes were downregulated, mainly associated with immune and inflammatory response (CHI3L1, LDAF1). Regarding the F2 fetuses, 151 DEGs were differentially expressed. Among them, 63 were upregulated in the MG group and involved with biological functions such as ion channels and transport (KCNAB1, SLC9A3), transcriptional regulation, and signaling (ZNF75D, TMEM106B, DPP6), enzymatic activity, and metabolism (B3GNT4, FAM20A, ALDH5A1, and PRSS23). Likewise, 88 downregulated genes were associated with the cell cycle and proliferation (APOOL, CIR1, and STIL). In conclusion, periconceptional maternal nutrition aimed at moderate weight gains can have multigenerational effects on the gene regulation of fetal muscle tissue.

Acute, subacute, repeat dose toxicity and safety studies of BiosimCovex (COVID-19 Nosode) in animal model

Introduction: BiosimCovex, a coronavirus nosode’s biological preparation was sourced from preclinical samples. The study needs to investigate the acute, subacute oral toxicity of different homeopathic drugs. The acute, subacute, repeat dose toxicity and safety testing of this newly developed nosode were conducted as per the OECD and New Drug and Clinical Trial (NDCT 19) rules. Material and methods In acute, subacute, repeat dose toxicity study, the homeopathic drug was administered orally at body weight, and animals were observed for toxic symptoms for 14 days. The study design consisted of 10 animals (05 males and 05 females) in acute mice and rats, 48 animals (24 males and 24 females) in subacute/repeat dose rats, and 24 (12 males/12 females) in repeat dose rabbit studies. Results Results indicate that in the acute and subacute studies of the rat and mice, no mortalities or clinical signs were found. The body weight and body weight gain in rats were normal and decreased in mice in the acute study. The feed consumption was normal for rats and mice. In male rabbits’ body weight was decreased and in other groups body weight gain observed was normal. The clinical signs were found to be normal in rats and rabbits. Histopathology results reveal that the BiosimCovex has not produced any major reactive and toxic changes in all the systemic organs when administered by an oral route up to a high dose. Conclusion No toxicity was documented using acute, subacute, and repeat dose studies using BiosimCovex, a coronavirus nosode.

Dietary Tenebrio molitor larvae meal effects on cellular stress responses, antioxidant statusand intermediate metabolism of Oncorhynchus mykiss.

In the context of evaluating the impact of environmentally friendly and sustainably produced alternative protein sources in fish feed, the present study's aim was to examine the overall physiological stress response in one of the main fish species of European freshwater aquaculture, Oncorhynchus mykiss (rainbow trout), following the partial substitution of fish meal (FM) with a Tenebrio molitor (TM) (yellow mealworm) full-fat meal. In total, 222 rainbow trout individuals (115.2 ± 14.2 g) were allocated randomly into six tanks, three per dietary treatment, and were fed a formulated diet containing 60% yellow mealworm (TM60) compared to a control diet without insect meal (TM0). Both diets contained equal amounts of crude protein, dry matter and, lipid content, while the FM in TM60 was 100 g kg-1 corresponding to the one seventh of the TM0. Heat shock response (HSR), MAPK signalling, cell death pathways (apoptosis and autophagy), antioxidant defence mechanisms, and intermediate metabolism were evaluated. In general, HSR and MAPK signalling were activated in response to the inclusion of T. molitor. Moreover, triggering of apoptotic and autophagic processes and the onset of antioxidant defence mechanisms underlined the existence of physiological stress. Despite the apparent dietary-induced stress, rainbow trout in the present study exhibited no mortality and no significant effects regarding growth performance parameters. Specifically, TM60 dietary inclusion resulted in no changes in final body weight, weight gain, and specific growth rate. However, feed intakedepicted a statistically significant decrease in TM60 fish compared to TM0 individuals. Nevertheless, nutrient stress should be considered a limiting factor regarding the utilization of T. molitor in O. mykiss diet due to the associated risks for health and welfare.

A true facultative carnivore? Effects of replacing ground chicken carcasses with soybean meal on the growth of captive broad-snouted caiman (Caiman latirostris) and its economics implications.

A specific diet for broad-snouted caiman, Caiman latirostris has not been designed despite the value of farm-raised caiman as an aquaculture product. To fill this gap, the objectives of this study were to evaluate the performance dietary replacement of ground chicken carcasses by of soybean meal (SM) as diet complement for C. latirostris. We conducted a 3-month growth trial to determine effects of graded levels of dietary SM on caiman growth as measured by increase in body length, body weight gain, food consumption (FC) and food conversion rate (FCR). Forty-eight hatchling caimans were fed with diets, composed primarily of practical feed ingredients, with 0, 25, or 40% dietary SM. Diets were fed three times per week for 90 days under temperature controlled. Body lengths and body weights were measured at 30-day intervals, and FC samples were taken between the 31-60-day interval. The results of this study indicate that the inclusion of SM in the diet of C. latirostris at levels of 25% increases in body length, body weight gain, FC and improve the FCR indicated that a concentration of 25% dietary SM (as fed) was adequate for growth of caimans under the conditions of this study. Results suggest that SM have a real nutritional contribution in the diet of broad-snouted caiman and can be used as an ingredient of the diet of the crocodilians raised in captivity, reducing production costs for sustainable use and conservation programs of this species.

Effect of Pure Corn Oil on Growth Performance of Japanese Quail (Coturnix Coturnix Japonica)

In recent years, consecutive research has been conducted on the nutrient requirements of the quails to find an optimum and affordable legitimate growth promoter. Different types of vegetable oil have been tested so far. This study aimed to evaluate the effects of pure corn oil (PCO) on growth performance and live body weight gain in Japanese quails. A total of 80 four-day-old quail chicks were divided into two groups: control (20 checks) and experimental (60 checks). The experimental group was subdivided into three subgroups (G1, G2, and G3) of 20 chicks per group. All the control and experimental group chicks were fed a commercial grower quail diet in all three growth phases. Despite the commercial diet, the G1, G2, and G3 experimental groups were fed 1, 3, and 5% PCO, respectively. The values for live body weight did not significantly change after adding PCO to the quail’s diet. According to the study's findings, adding PCO to the commercial diet of Japanese quails in various amounts had no beneficial effects on feed consumption and growth rate. Additionally, it had an insignificant (p>0.05) detrimental impact on the growth performance of the quails compared to control groups. In conclusion, we can say that adding PCO to quail's commercial diet in the hot months of the year under Afghanistan's climate has no positive impact on growth and further slows down the rate of body weight gain.

Effect of Dietary Vitamin C Supplementation on Growth Performance and Biochemical Parameters in Grower Walleye Pollock, Gadus chalcogrammus.

The optimal dietary vitamin C (VC) levels for walleye pollock (Gadus chalcogrammus) remain undefined. This study aimed to assess the effect of dietary VC levels on the growth performance and biochemical parameters of grower walleye pollock and determine the optimal VC level for their diet. Six experimental diets (VC0, VC1, VC3, VC5, VC7, and VC10) with VC levels of 3.24, 21.92, 63.31, 101.42, 145.46, and 202.51 mg kg-1 diet, respectively, were fed to fish (initial mean weight: 173.5 ± 0.31 g) for 8 weeks. At the end of the feeding trial, fish fed the VC7 and VC10 diets exhibited significantly higher growth (final body weight, weight gain, and specific growth rate) and improved feed utilization (feed efficiency and protein efficiency ratio) compared with fish fed the VC0 diet (p < 0.05). The VC3-VC10 diets significantly reduced plasma superoxide dismutase (SOD) activity (p < 0.05). Compared with the VC0 group, fish fed the VC7 and VC10 diets showed significantly elevated growth hormone and insulin-like growth factor-1 levels in plasma (p < 0.05). In conclusion, dietary VC supplementation in walleye pollock improved growth performance and SOD activity. Moreover, broken-line analysis on weight gain indicated that the optimal dietary VC level for grower walleye pollock was approximately 156.42 mg kg-1 diet.

Black Soldier Fly Larvae Meal vs. Soy Protein Concentrate Meal: A Comparative Digestibility Study in Barramundi (Lates calcarifer)

Black soldier fly larvae meal (BSFM) from Hermetia illucens has emerged as a dependable protein source in aquaculture. This study aimed to assess BSFM’s digestibility in barramundi juveniles and compare it to soy protein concentrate meal (SPCM). Four diets (control, 30% BSFM; 30% SPCM; and commercial feed control) were tested on 1,800 barramundi juveniles (weight: 71.1 g) over 51 days in a recirculating aquaculture system (RAS). The final body weight (FBW) of fish fed with BSFM reached 222.2 (± 8.7), with a thermal-unit growth coefficient (TGC) of 4.33 (± 0.15) and a feed conversion ratio (FCR) of 1.04 (± 0.01). While BSFM and SPCM inclusion did not significantly impact FBW, body weight gain (BWG), TGC, or survival rates (P &gt;0.05), FCR increased. BSFM significantly raised total feed intake (P&lt;0.05) but did not affect daily feed intake (P &gt;0.05). Importantly, BSFM and SPCM inclusion did not alter diet apparent digestibility coefficient (ADC) for any nutrient groups (P &gt;0.05), with BSFM showing high ADC for dry matter (76.8%), crude protein (93.2%), and gross energy (83.9%). No significant difference (P &gt;0.05) was observed in these ADCs between BSFM and SPCM. The high digestibility of BSFM in warm seawater RAS (29.4°C) under high stocking density (33.7 kg m−3) supports its efficacy in contemporary barramundi farming.

Dietary Supplementation of Astragalus membranaceus Extract Affects Growth Performance, Antioxidant Capacity, Immune Response, and Energy Metabolism of Largemouth Bass (Micropterus salmoides).

The present study investigated the effects of Astragalus membranaceus extract (AME) on growth performance, immune response, and energy metabolism of juvenile largemouth bass (Micropterus salmoides). Seven diets containing 0%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, and 0.6% AME (Con, AME0.1, AME0.2, AME0.3, AME0.4, AME0.5, and AME0.6 groups) were formulated and fed to M. salmoides for 8 weeks. Final body weight (FBW), feed intake (FI), weight gain (WG), and specific growth rate (SGR) were all significantly higher in AME0.4 group than in Con group (P < 0.05). Feed conversion rate (FCR) was significantly improved in AME0.5 group compared with Con group (P < 0.05). Whole-body crude protein contents were significantly increased in AME0.2 group (P < 0.05). Whole-body crude lipid contents were significantly lower in AME0.2 and AME0.3 groups, while muscle lipid was upregulated by dietary AME (P < 0.05). Hepatic malondialdehyde (MDA) contents were significantly lowered in AME0.3 and AME0.4 groups, and catalase (CAT) activities were significantly increased in AME0.1 and AME0.2 groups (P < 0.05). Plasma aspartate aminotransferase (AST) level was significantly lowered in AME0.5, and AME0.6 groups, and alanine aminotransferase (ALT) level was lowered in AME0.5 groups (P < 0.05). Plasma triglyceride was declined in AME0.6 group, and glucose was decreased by 0.3%-0.5% AME (P < 0.05). Significantly higher hepatocyte diameter, lamina propria width, and submucosal layer thickness were recorded in AME0.6 groups, while the longest villi height was obtained in AME0.2 and AME0.3 groups (P < 0.05). The mRNA expression levels of insulin-like growth factor 1 (igf1) revealed the growth-promoting effect of AME. The anti-inflammatory and antiapoptotic effects of AME were demonstrated by transcription levels of interleukin 8 (il-8), tumor necrosis factor-alpha (tnf-a), caspase, B-cell lymphoma-xl (Bcl-xl), bcl-2 associated x (Bax), and bcl-2-associated death protein (Bad). The transcription levels of lipid metabolism and gluconeogenesis related genes, including acetyl-CoA carboxylase alpha (acc1), fatty acid synthase (fasn), fatty acid binding protein 1 (fabp1), phosphoenolpyruvate carboxykinase 2 (pepck2), and glucose-6-phosphatase catalytic subunit 1a (g6pc), were reduced by AME treatment, while the levels of glycolysis-related genes, including glucokinase (gck) and pyruvate kinase (pk), were the highest in AME0.2 and AME0.3 groups (P < 0.05). According to polynomial regression analysis of SGR, WG, FCR, whole-body crude lipid, MDA, and ALT, the optimal AME supplementation level was estimated to be 0.320%-0.429% of the diet. These results provided insights into the roles of AME in regulating immunity and metabolism, which highly indicated its potential as immunostimulants and metabolic regulators in diverse aquatic animals.

Changes of nutrient composition in the ovaries and hepatopancreas of mud crab Scylla paramamosain broodstock and their offspring performance at different salinities

The mud crab Scylla paramamosain is a major marine crab species for aquaculture in the southern coastal regions of China. This study investigated the differences in the quality of low-salt cultured and wild mud crabs and the the salinity tolerance and growth performance of their offspring. Ovarian development and fatty acid and amino acid compositions in the hepatopancreas and ovaries of mature low-salt and wild mud crabs were compared. The gonadosomatic index was significantly lower, but the hepatopancreatic index was significantly higher in the low-salt mud crab than in the wild mud crab. The contents of C18:1, C22:6n3 (DHA), DHA/EPA, and n-3/n-6 fatty acids in the ovaries and hepatopancreas of the low-salt mud crab were significantly higher than those of the wild mud crab. Except for proline in the hepatopancreas of the low-salt group, there were no significant differences in amino acids in the ovaries and hepatopancreas between the two groups. Although the survival rate of larval mud crabs in the low-salt mud crab was significantly higher than that in the wild mud crab when the salinity was 24‰, there was no significant difference in the juvenile survival between the two groups. However, the survival rate of larval and juvenile mud crabs in the low-salt group was significantly higher than in the wild group when the salinity was 5 ‰ and 3 ‰, respectively. The final body weight, average weight, weight gain, and specific weight gain rate of male and female offspring in the low-salt group were significantly higher than in the wild group. However, the weight gain and specific growth rate of male offspring in the low-salt group in September–October were significantly lower than those of male mud crabs in the wild group. This study indicates that the mud crab can be domesticated for culture and breeding at low salinity.

Effects of Photoperiod on Survival, Growth, Physiological, and Biochemical Indices of Redclaw Crayfish (Cherax quadricarinatus) Juveniles

Through a 30-day experiment, this study investigated the effects of five photoperiods (0L:24D, 6L:18D, 12L:12D, 18L:6D, and 24L:0D) on the survival, enzyme activity, body color, and growth-related gene expression of redclaw crayfish (Cherax quadricarinatus) juveniles. The results showed that C. quadricarinatus juveniles under 18L:6D and 24L:0D photoperiods exhibited the highest survival rate, which was significantly higher than the survival rates of juveniles under the other three photoperiods (p &lt; 0.05). However, the 0L:24D group had the highest final body weight and weight gain rate, significantly surpassing those of the 12L:12D, 18L:6D, and 24L:0D groups (p &lt; 0.05). Regarding enzyme activity and hormone levels, juveniles under the 18L:6D photoperiod exhibited relatively higher activity of superoxide dismutase (SOD), acid phosphatase (ACP), and lysozyme (LZM) enzymes than those under other photoperiods, but their levels of melatonin and cortisol were relatively low. In addition, the 24L:0D group showed the highest malondialdehyde (MDA) content. Analysis of gene expression levels revealed that retinoid X receptor (RXR) and α-amylase (α-AMY) genes in C. quadricarinatus juveniles exhibited significantly higher expression levels under the 18L:6D photoperiod than those under the other four photoperiods (p &lt; 0.05). With increasing daylight exposure, the body color of C. quadricarinatus changed from pale blue to yellow–brown. In summary, C. quadricarinatus juveniles achieved high survival rates, good growth performance, strong antioxidant stress response, and immune defense capabilities under an 18 h photoperiod. Therefore, in the industrial seedling cultivation of redclaw crayfish, it is recommended to provide 18 h of daily light. Further, the study demonstrated the ability to manipulate the body color of C. quadricarinatus through controlled artificial photoperiods. These findings provide essential technical parameters needed for the industrial cultivation of C. quadricarinatus juveniles.

Effect of low doses of active chlorine on commensal populations of intestinal bacteria in rats by oral ingestion

Chlorine-containing substances are widely used as disinfectants for treating equipment surfaces and technological aids for antimicrobial treatment of a number of foodstuff in the food industry. The toxic and bactericidal effects of the active (free) chlorine they contain are well understood for the concentrations used in practice, whereas little is known about the effect of its residual (subinhibitory) amounts on the organism and on the microbiota, including the ability to induce antimicrobial resistance. The aim of the study was to investigate the effect of different doses of active chlorine at oral administration on the commensal bacteria of intestinal microbiota, body weight gain and micromorphological features of the liver in rats. Material and methods. The study was carried out on male Wistar rats, with an initial body weight of 90-100 g, which for 4 weeks received doses of active chlorine together with drinking water ad libitum, with the given concentration: subinhibitory (10 mg/L), threshold (50 mg/L) and aggravated (100 mg/L). Chloramine was used as a chlorinecontaining agent stable in aqueous solution. Body weight gain was monitored daily. After decapitation, the caecum was taken for microbiota examination as well as the liver. The phenotypic antimicrobial resistance characteristics of Enterobacteriaceae and Enterococci were studied by the disk diffusion method. Additionally, a micromorphologic study of liver slices was performed. Results. Insignificant negative deviations in the body weight gain of rats in the experimental groups receiving subinhibitory doses of active chlorine, combined with a reduced level of Enterococci and Enterobacteriaceae representatives, were revealed. No significant effect of chlorine on the levels of resistant Escherichia coli populations was found, but a tendency to exhibit antimicrobial resistance of Enterococci isolated from rats receiving low doses of active chlorine (10 and 50 mg/l) was detected. No signs of toxic effect on the liver tissue most sensitive to chlorine were detected, but some accumulations of inflammatory cells in the liver slice were revealed. Conclusion. Low doses of chlorine-containing substances at their oral consumption are not indifferent for rats' organism, causing negative phenomena in intestinal bacteria and in liver tissues at the level of tendency. It is expedient to continue studies in this direction.

THE ROLE OF CASTRATION BEFORE OR AFTER PUBERTY ON SEX DIFFERENCES IN GROWTH AND LONGEVITY IN UM-HET3 MICE

Abstract Sex differences in human aging and longevity are well known. Mortality rates of males are higher throughout life with no definitive mechanisms identified. Previously, we reported that genetically heterogeneous mice have sex differences in longevity like those of humans. Here, we report that prepubertal castration significantly reduced early adulthood mortality and increased median lifespan by 12.6% (n=236/group) to match female levels. It also shifted growth trajectories toward the female pattern, including a reduced rate of body weight gain and a prolonged growth period. Our findings suggest that testicular hormones are critical for these sex differences. We next tested whether a) exposure to gonadal hormones from puberty throughout life is required or b) only hormone exposure during the short period of pubertal development is sufficient to cause these sex differences. We castrated or sham-operated mice (n = 60/group) prepubertally at 20 days, or after puberty at 60 or 240 days. Prepubertal castration prolonged the period of growth as before, with dramatically increased fat mass and reduced lean mass, which reduced the lean/body mass ratio to a level indistinguishable from that of females. Although post-pubertal castrated groups also had reduced lean/body mass ratios, they were significantly higher than prepubertally castrated mice, but were unchanged between 60d and 240d groups. These results suggest that the narrow window of testicular hormone exposure during puberty is necessary for the full expression of sex differences in body composition trajectories. Its effect on lifespan will be presented at the meeting when mice are old enough for assessment.

Long-Term Effects of Campylobacteriosis in Infants

Background. Campylobacteriosis is the leading cause of bloody diarrhea worldwide. Infants have high risk severe campylobacteriosis as well as development of complications affecting the child growth and development. Objective. The aim of the study is to evaluate the long-term effects of campylobacteriosis in infants. Methods. A multicenter, prospective, dynamic, open, observational study included 80 children aged from 3 months to 2 years. The follow-up period after campylobacteriosis was 12 months. Patients were divided into three groups according to the feeding type: 1 — acidified milk formulas, 2 — non-acidified milk formula without a probiotic, 3 — breastfeeding. Physical examination data and anthropometric indicators were evaluated: height, body weight and z-indices. Moreover, qualitative and quantitative indicators of microbiocenosis were evaluated on the 21st day from the disease onset. Results. Functional gastrointestinal disorders (FGID) were diagnosed in 17 children (42.50%) at the follow-up period after campylobacteriosis: functional constipation (n = 11; 27.5%), functional diarrhea (n = 3; 7.50%), infantile colic (n = 2; 5.00%), cyclic vomiting syndrome (n = 1; 2.50%). Disorders of intestinal microbiocenosis were characterized by Bifidobacterium spp. and B. thetaiotaomicron decrease in all groups. Patients with FGID after campylobacteriosis had profound decrease in the level of Bifidobacterium spp., F. prausnitzii and B. thetaiotaomicron, and slower rate of body weight gain. The more profound decrease in body weight gain rates was observed in patients with initially low indicators. 10 (25.00%) patients after campylobacteriosis had no slowdown in body weight gain. 5 of them were administered with acidified milk formula during the convalescence period. 7 children (17.5%) had a decrease in weight-to-age ratio relevant to body weight deficiency, while 6 children (15.0%) moreover had malnutrition in BMI-to-age index significantly more frequently (p = 0.0050) with non-acidified milk formula without a probiotic after completion of the follow-up. Conclusion. The inclusion of children on formula feeding in the complex of therapeutic measures (with acidified milk formulas with probiotics) contributes to the improvement of qualitative and quantitative indicators of microbiocenosis and the rapid restoration of the body weight gain and growth rates.

Effects of supplemental phytase on growth, nutrient digestibility and anti-oxidant enzyme activity in the gills of juvenile mrigal, Cirrhinus mrigala (Hamilton 1882) fed distillers dried grains with soluble based diets

ABSTRACT A 90-day feeding trial was conducted to investigate the effects of phytase supplemented Distiller’s Dried Grains with Soluble (DDGS) based diet on the production performance, tissue composition, nutrient digestibility and activity of anti-oxidant enzymes in the gills of mrigal (Cirrhinus mrigala) juveniles. Six experimental diets were formulated to contain increasing levels of supplemental phytase, 0 (D1), 250 (D2), 500 (D3), 750 (D4), 1000 (D5), and 1250 (D6) phytase (FTU/kg). Each experimental diet was randomly assigned and fed three times daily to triplicate groups of 180 fish. Significant increase in body weight gain and specific growth rate, feed conversion and protein efficiency ratios of groups fed up to 750 FTU/kg were observed. Broken line analysis of Specific Growth Rate showed that the optimal dietary phytase level of mrigal juveniles is 750 FTU /kg or higher than this dose. Results among protein, lipid, moisture, ash and P contents of whole body, muscle, liver and viscera were not significantly different as phytase level increased from 250 FTU/kg to 1250 FTU/kg (D2 to D6). It was concluded that phytase at the rate of 750 FTU /kg is the optimum dose for the enhanced growth in juvenile mrigal.

Effects of Low-Fish-Meal Diet Supplemented with Coenzyme Q10 on Growth Performance, Antioxidant Capacity, Intestinal Morphology, Immunity and Hypoxic Resistance of Litopenaeus vannamei.

The aim of this study was to evaluate the effects of a low-fish-meal diet supplemented with coenzyme Q10 on the growth, antioxidant capacity, immunity, intestinal health and hypoxic resistance of Litopenaeus vannamei. L.vannamei with an initial weight of 0.66 g were fed with the experimental diets for 56 days. Diets D1 (20% FM level) and D2-D7 (15% FM level), supplemented with 0%, 0.002%, 0.004%, 0.006%, 0.008% and 0.01% coenzyme Q10 were formulated. In terms of growth performance, the weight gain and specific growth rate in the D2 diet were significantly lower than those in the D1 diet (p < 0.05). The final body weight, weight gain and specific growth rate in the D2-D7 diets had an upward trend, and the condition factor in the D2-D7 diets was lower than those in the D1 diet (p < 0.05). There were no significant differences in the crude protein and crude lipid levels in the whole body among all diet treatments (p > 0.05). In terms of hepatopancreas antioxidant parameters, the D5 and D6 diets significantly promoted the total antioxidant capacity and total superoxide dismutase activity, and significantly decreased the malondialdehyde content (p < 0.05). The expression levels of cat, mnsod and gpx in shrimp fed with the D5 and D6 diets were significantly higher than those of shrimp fed with the D2 diet (p < 0.05). In addition, the mRNA level of ProPO was increased in the D4 and D5 diets, and LZM expression was increased in the D6 diet compared with the D1 diet (p < 0.05). The villus height of shrimp fed with diets supplemented with coenzyme Q10 was significantly increased (p < 0.05), and the intestinal thickness and submucosal thickness of shrimp fed with the D6 diet were the highest (p < 0.05). After acute hypoxia stress, lethal dose 50 time in the D3-D7 diets was significantly increased compared with the D1 and D2 diets (p < 0.05), and the highest value was found in the D4 diet (p < 0.05). After stress, the expression levels of TLR pathway-related genes (Toll, Myd88, Pelle, TRAF6 and Dorsal) in the D4 and D6 diets were significantly increased compared with the D2 diet. In general, Litopenaeus vannamei fed with the D6 diet achieved the best growth, antioxidant capacity, immunity, and intestinal morphology among all low FM diets and D4-D6 diets improved hypoxic resistance.

The effects of enrofloxacin exposure on responses to oxidative stress, intestinal structure and intestinal microbiome community of largemouth bass (Micropterus salmoides)

Antibiotic residues in the aquaculture environments may lead to antibiotic resistance, and potentially exert adverse effects on health of the non-target organisms and humans. In order to evaluate the effect of enrofloxacin of environmental concentrations on largemouth bass (Micropterus salmoides). Two hundred and seventy largemouth basses (with an average weight of 7.88 ± 0.60 g) were randomly divided into three groups, and separately exposed to 0, 1, 100 μg/L enrofloxacin (Control, ENR1, ENR100) for 30 days to detect the effect of enrofloxacin on the growth performance, oxidative stress, intestinal microbiota structure, inflammatory response and structure of the intestine. The results showed that ENR significantly reduced the final body weight (FBW) and weight gain rate (WGR), and increased feed conversion ratio (FCR) (P < 0.05). The histopathological analysis revealed that the villus width and muscular thickness of anterior intestine were significantly decreased with the increasing of enrofloxacin concentration. The activity of SOD was significantly increased at enrofloxacin stress, while CAT and POD activity were significantly decreased compared to control group (P < 0.05). The activities of lysozyme (LZM), alkaline phosphatase (AKP) and peroxidase (POD) in ENR1 was higher than that of control and ENR100 groups. Enrofloxacin treatment up-regulated the expression IL-1β and TNF-α, and down-regulated IL-10, and decreasing the expression level ZO-1, claudin-1, and occludin. Furthermore, the enrofloxacin treatment significantly decreased the intestinal bacterial diversity (P < 0.05). Exposure to 100 μg/L enrofloxacin obviously increased the relative abundance of Bacteroidota, Myxococcota, and Zixibacteria of fish gut, and reduced Firmicutes; 1 μg/L enrofloxacin considerably increased Bacteroidota, Myxococcota, and Actinobacteria, and reduced Firmicutes. The relative abundance of DTB120 and Elusimicrobiota was positively correlated with the occludin and claudin-1 gene. Taken together, exposure to enrofloxacin inhibited the growth of largemouth bass, influenced intestinal health, and induced dysbiosis of the intestinal microbiota.

Stocking density affects culture performance and economic profit of adult all-female Chinese mitten crabs (Eriocheir sinensis) reared in earthen ponds

As female Chinese mitten crab (Eriocheir sinensis) generally offer the higher edible yield, greater nutritional value, and consequently, higher market price compared to males, therefore all-female monosex culture has been popularized for the farming E. sinensis. However, the optimal stocking density remains unknown for all-female culture of E. sinensis. The present study was conducted to evaluate the effect of different stocking densities (D1.3: 1.3 inds/m2, D1.9: 1.9 inds./m2, D2.5: 2.5 inds./m2 and D3.8: 3.8 inds./m2) on growth performance, gonadal development, and economic profits of all-female E. sinensis during nine months culture period. The results showed that all growth parameters including mean body weight, body weight gain (BWG) and specific growth rate (SGR), exhibited an inverse relationship with stocking density. However, stocking density did not have a significant effect on the percentage of puberty molting, gonadosomatic index (GSI) and hepatosomatic index (HSI). At the end of the experiment, the survival rate significantly decreased with the increasing stocking density, while both final production yield and economic feed conversion ratio (eFCR) significantly increased with stocking density (P < 0.05). Profitability analysis showed that total cost and total return increased significantly with the stocking density, but the highest net profit (129.68 × 103 CNY/ha) and return-on-investment (ROI, 87.65%) were achieved at the D2.5 group. Overall, these results suggested that the optimal stocking density might range from 1.9 to 2.5 individuals/m2 in grow-out ponds for all-female mono-culture of E. sinensis.