Growth Performance Research Articles

Pathogenicity of psychrotolerant strains of Antarctic Pseudogmynoascus fungi reveals potential opportunistic profiles

Recent studies have demonstrated the presence of fungal taxa in the extreme ecosystems of Antarctica that are known to opportunistically infect humans and animals. Among these are members of the genus Pseudogymnoascus, including some that are genetically similar to P. destructans, known to be pathogenic to bats. We evaluated the in vitro and in vivo pathogenic potential of 11 Pseudogymnoascus spp. strains recovered from Antarctica. All strains were able to grow at temperatures up to 28 °C and displayed in vitro pathogenicity through hemolytic activity, growth at different pH levels, production of hydrolytic enzymes, spore diameters, tolerance to oxidative stress, hypoxia, and halotolerance. Among them, Pseudogymnoascus sp. UFMG 8532 exhibited strong in vitro pathogenicity and in preliminary in vivo assay killed 100% of Tenebrio molitor larvae within one day. The pathogenicity of the same strain was also tested using immunosuppressed BALB/c mouse models. Survival of BALB/c mice was affected, with oscillations between weight gain and loss, and impacts on sensory function, reflexes and autonomic function. Histopathological data from the organs of infected mice showed evidence of inflammatory processes, with numerous neutrophils, a small number of macrophages, fluid accumulation inside the lungs and intense hyperemia. Our results indicate that Antarctic Pseudogymnoascus spp. strains obtained from various substrates/habitats in maritime Antarctica may possess intrinsic virulence factors and pathogenic potential for immunosuppressed animals and humans in the region. Given that the Antarctic environment is an important reservoir for Pseudogymnoascus species, which display growth performance across a range of temperatures, it is possible that increasing temperatures in the maritime Antarctic could activate dormant genes, biochemical pathways, select virulent species and/or strains, and facilitate their spread within and beyond the region. The ability of Pseudogymnoascus species to grow slowly even at 28°C, coupled with their potential in vitro and in vivo virulence factors, suggests that these fungi might be undergoing an opportunistic transition due to the effects of climate change on the Antarctic Peninsula.

Genome‐wide association study and genomic prediction for growth traits in spotted sea bass (Lateolabrax maculatus) using insertion and deletion markers

AbstractSpotted sea bass (Lateolabrax maculatus) is a species of significant economic importance in aquaculture. However, genetic degeneration, such as declining growth performance, has severely impeded industry development, necessitating urgent genetic improvement. Here, we conducted a genome‐wide association study (GWAS) and genomic prediction for growth traits using insertion and deletion (InDel) markers, and systematically compared the results with our previous studies using single nucleotide polymorphism (SNP) markers. A total of 97 significant InDels including a 6 bp insertion in an exon region were identified. It is worth noting that only 5 and 1 candidate genes for DY and TS populations were also detected in previous GWAS using SNPs, and numerous novel genes including c4b, fgf4, and dnajb9 were identified as vital candidate genes. Moreover, several novel growth‐related procedures, such as the growth and development of the bone and muscle, were also detected. These findings indicated that InDel‐based GWAS can provide valuable complement to SNP‐based studies. The comparison of genomic predictive performance for total length trait under different marker selection strategies and genomic selection models indicated that GWAS selection strategy exhibits more stable predictive performance compared to the evenly selection strategy. Additionally, support vector machine model demonstrated better predictive accuracy and efficiency than traditional best linear unbiased prediction and Bayes models. Furthermore, the superior predictive performance using InDel markers compared to SNP markers highlighted the potential of InDels to enhance genomic predictive accuracy and efficiency. Our results carry significant implications for dissecting genetic mechanisms and contributing genetic improvement of growth traits in spotted sea bass through genomic resources.

Polysaccharides from Enteromorpha prolifera improve growth performance and are involved in regulation of immune responses and microbial communities in the sea cucumber, Apostichopus japonicus (Selenka, 1867)

Polysaccharides from Enteromorpha prolifera improve growth performance and are involved in regulation of immune responses and microbial communities in the sea cucumber, Apostichopus japonicus (Selenka, 1867)

Effect of Solid-State Fermentation Products of Lactobacillus plantarum, Candida utilis, and Bacillus coagulans on Growth Performance of Broilers and Prevention of Avian Colibacillosis

This study investigates the impact of the solid-state fermentation products of Lactobacillus plantarum, Candida utilis, and Bacillus coagulans (LCBs) on the growth characteristics, immune function, intestinal morphology, cecum microbial community, and prevention of avian colibacillosis in broilers. One hundred and twenty Hyland Brown broilers (aged one day) were divided randomly into three groups (four replicates of ten broilers per group). (1) The CON group was fed a basal diet. (2) The MOD group was fed a basal diet. On day 40, APEC strain SX02 (1.1 × 105 CFU/g) was administered to the breasts of chickens in this group. (3) The LCBs group was fed a basal diet supplemented with fermentation products (98.5% basal diet + 0.5% Lactobacillus plantarum and Candida utilis solid-state fermentation products + 1.0% Bacillus coagulans solid-state fermentation products). On day 40, the LCBs group received the same treatment as the MOD group. The experiment lasted 43 days. This study found that the average daily gain (ADG) of the LCBs group was significantly higher than that of the MOD group (p < 0.05), indicating that LCBs can significantly increase the ADG of broilers and improve the feed conversion ratio. Furthermore, compared to the MOD group, the heart bacterial load was significantly reduced in the LCBs group (p < 0.05), and the lesions less severe in the heart, liver, and jejunum were observed (p < 0.05). Additionally, the detection of intestinal flora showed a significant increase in the abundance of beneficial bacteria in the cecum of the LCBs group, while the number of Escherichia coli and Shigella decreased significantly. In conclusion, the solid fermentation of Lactobacillus plantarum, Candida utilis, and Bacillus coagulans can improve the growth performance of broilers while also protecting against avian pathogenic Escherichia coli infection. This demonstrates the potential usefulness of these LCBs in feed production.

Microalgae as feed additives in poultry: A review on the health-promoting effects

This review explores the effects of the inclusion of microalgal biomass in feed on the health of poultry (broilers and laying hens). Microalgae have emerged as a promising feed additive, valued not only for their rich nutritional profile, but also for their bioactive substances. Bioactive compounds, such as phenolics, polyunsaturated fatty acids, oligosaccharides and carotenoids, exhibit antioxidant, anti-inflammatory, antibacterial, and antiviral functions, which hold promise for promoting poultry health. With the ban on prophylactic antibiotic use in feed, microalgal biomass emerges as an innovative feed additive to enhance growth performance and prevent health issues in poultry. This review extensively explains the critical health parameters of poultry, including histology of the intestinal tract, intestinal permeability, immunity, antioxidant status and prebiotic effects on the intestinal microbiome. Furthermore, it offers valuable insights into the inclusion of microalgae in poultry feed, promoting these health parameters. It concludes with suggestions for further research and practical recommendations on how to improve poultry health using microalgal biomass.

Effects of oxygen levels and temperature on growth and physiology of pikeperch juveniles cultured in a recirculating aquaculture system

This study aimed to understand how environmental factors, specifically water temperature and oxygen saturation, affect the growth performance and physiology of pikeperch (Sander lucioperca) juveniles in recirculating aquaculture systems (RAS). Given the importance of optimizing growth conditions in aquaculture to maximize efficiency, it aims to assess whether different combinations of oxygen levels and temperatures can enhance growth while maintaining the physiological health and welfare of the fish. The experimental design included the culturing pikeperch juveniles (22.7±7.1 g) were exposed to hypoxia (78±14%), normoxia (105±12%), and hyperoxia (140±18%) conditions for 72 days. This was conducted at two temperatures, 20°C and 23°C, each in a separate but identical RAS. The level of oxygen supply was controlled with micro bubble diffusers on the bottom of each tank. The hyperoxia at 23 °C positively affected total length, body weight, specific growth rate, feed intake and feed conservation rate (FCR). The slowest growth and feed intake, along with the highest FCR, were observed in hypoxia at 20 °C. Fish reared under 23 °C exhibited significantly higher visceral-somatic index (3.54 ± 0.83 at 23 °C and 2.76 ± 0.73 at 20 °C) regardless of oxygen levels. It was primarily responsible for the observed growth difference (Final BW: 58.3 ± 18.8 g at 23 °C and 53.0 ± 18.3 g at 20 °C). The water temperature also affected haematocrit, haemoglobin, leucocyte count, mean corpuscular haemoglobin, mean corpuscular volume (MCV) of the blood cells; the concentration of lymphocytes, neutrophile granulocyte bands and segments. Among biochemical markers, temperature affected cytoplasmic and mitochondrial enzymes, ammonia and triglyceride levels in blood plasma. Elevated antioxidant activity was observed in muscle, intestine and liver tissues. Oxygen levels demonstrated significant effects on growth, feed intake and conversion, the MCV of the blood cells, the concentration of the glucose, lactate and ammonia in blood plasma, and antioxidant biomarkers in the liver tissue. The analysis indicated significant effect of oxygen on energy metabolism. The results showed hyperoxia under 23 °C create conditions for the highest growth and feed intake, high feed utilization. There are, however, concerns about physiological conditions and welfare of intensively cultured pikeperch juveniles, as higher feed intake led to increased visceral fat content in the body, elevated antioxidant activity in the liver, muscle and intestine tissues, morphology of blood cell, and energy metabolism.

The impact of host genetics on microbe assemblages in three types of mrigal carp (Cirrhinus mrigala)

Host–microbiota interactions are molecular and physical interactions between the microbiota and the host that play significant roles in the lifespan of animals. In the present study, two types of gynogenetic mrigal carp (GMCC and GMCW) and the original maternal mrigal carp (MC) were used as a models to investigate host–microbiota interactions. The two types of gynogenetic mrigal carps showed faster growth and better cold tolerance than the MC fish. Compared to those in MC, a large number of goblet cells and higher activity of cellulase and pepsin were detected in the intestine of gynogenetic fish. The composition and abundance of the microbial communities significantly differed among the three types of mrigal carp and water, with Proteobacteria, Firmicutes and Chloroflexi being the most dominant microbes in the GMCC, GMCW and MC fish, respectively. Pseudomonas, Lactococcus and Defluviicoccus were the biomarker genera in the GMCC, GMCW and MC fish. Network analysis revealed no relationships between fish and water, but the dominant genera was positively correlated with the abundance of certain enzymes. Functional analysis revealed the dominant genera associated with amino acid metabolism, fatty acid metabolism and bile acid biosynthesis. Our results suggested that host genetics may affected gut microbe assembly and that the specific metabolic functions of gut microbes may contribute to growth performance through the microbe-gut-liver axis.

Dietary Lithospermum erythrorhizon ethanol extract alleviates soybean meal-induced enteritis by improving immune tolerance profile of pearl gentian grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂)

The aquaculture industry has a shortage of objected protection against soybean meal-induced enteritis (SBMIE) in carnivorous fish caused by soybean meal feed. Our initial study discovered that Lithospermum erythrorhizon (LE) ethanol extract has potential application value in improving SBMIE. A feeding trial (for eight weeks) was conducted to investigate LE ethanol extract on pearl gentian grouper SBMIE of protection to clarify the influence of LE ethanol extract on the immune tolerance profile. Three hundred and sixty pearl gentian groupers were administered one of three distinct dietary regimes: 1) 100 % fish meal (FM); 2) soybean meal substitution of 50 % fish meal protein (SBM); 3) SBM diet +0.2 % LE ethanol extract (SBMLE). Each treatment included three 1000 L cisterns—each of cisterns with 30 fish. The preliminary weight of the fish varied between 72.01 g and 72.50 g. Growth performance results showed that WGR and SGR were significantly decreased in the SBM group (P < 0.05), while there was no significant difference between the FM and SBMLE groups. There was no significant difference in survival among the three groups. The results showed that SBM-fed fish exhibited enteritis manifested by mucosal fold shortening, lamina propria widening, decreased serum immune markers (IgM, C3, and C4), and up-regulated expression of pro-inflammatory cytokines (il17 and il12) and immune-related gene (tlr3, and tlr9). The addition of 0.2 % LE ethanol extract to the SBM diet, reversed the above symptoms, and anti-inflammatory cytokine (tgf-β1), gene expression increased significantly (P < 0.05). Intestinal transcriptome analysis exhibited that the DEGs between the FM group and the SBM group were mainly enriched in FoxO signaling pathway, while the DEGs between the SBM group and the SBMLE group were enriched in MAPK signaling pathway and FoxO signaling pathway. The RT-qPCR results also revealed changes in MAPK/FoxO signaling pathway-related genes, including Dusp1, jund, Irs2b, fbxo32, and ccng2. Overall, Lithospermum erythrorhizon ethanol extract may alleviate SBMIE by regulating MAPK/FoxO signaling pathway, which would be beneficial for enhancing the immune tolerance and utilization efficiency of pearl gentian groupers to dietary soybean meal.

Unraveling growth-promoting potential of plant beneficial actinobacteria on tropical bryophytes

Bryophytes are non-vascular plants with dominant gametophyte stage that play vital ecological roles in natural ecosystems. Unfortunately, their populations are currently in decline due to habitat destruction and various anthropogenic activities. The conservation efforts for bryophytes are hampered by their slow growth rates. This study aims to investigate the potential of actinobacteria to promote the growth of bryophytes. In this study, three plant growth-promoting actinobacteria, Dermacoccus abyssi MT1.1T, Micromonospora chalcea CMU55-4 and Streptomyces thermocarboxydus S3 were cultured in International Streptomyces Project medium 2 (ISP2) broth to obtain culture filtrates containing bioactive compounds for enhancing the growth of two bryophyte species, Physcomotrium sphaericum (C. Ludw.) Fürnr and Sphagnum cuspidatulum C. Müll. Interestingly, the incorporation of actinobacterial culture filtrates into 1/16 Murashige and Skoog (MS) medium yielded superior growth performance of P. sphaericum (C. Ludw.) Fürnr and S. cuspidatulum C. Müll, as observed from the thallus height, fresh weight, total chlorophyll contents, and total carotenoid contents compared to control groups. In addition, the inoculation of M. chalcea CMU55-4 on S. cuspidatulum C. Müll grown in sterile peat moss demonstrated the highest values for thallus height, fresh weight, dry weight, total chlorophyll content, and total carotenoid content. All actinobacteria successfully colonized the moss seedlings without any observable negative impacts, indicating beneficial interactions between actinobacteria and bryophytes. This research sheds light on the potential of harnessing plant beneficial actinobacteria to enhance the growth of bryophytes for conservation purposes.

Effect of 25-hydroxycholecalciferol and high phytase doses on performance, vitamin D status, bone mineralization, and mTOR kinase gene expression of broilers

The use of exogenous phytase and vitamin D3 metabolites such as 25-hydroxycholecalciferol (25-OH-D3) for poultry is well consolidated, but the potential for additive effects when supplementing both requires further investigation. This study investigated possible interactions between supplementation of 25-OH-D3 and high doses of phytase for broilers fed Ca and P-deficient diets. A total of 1 200 one-d-old male broiler chicks were randomly allocated from to 1 of 4 dietary treatments in a 2 x 2 factorial arrangement: 600 or 2 000 phytase units (FYT)/kg and with or without the inclusion of 25-OH-D3 at 69 µg/kg, with 12 replicates of 25 broilers each. Two feeding phases were stablished (1-to-21 and 22-to-42 d) and all diets contained commercial levels vitamin D3 (100 µg/kg) with total Ca and available P respectively set to 0.6 and 0.3%. Supplementation with 25-OH-D3 increased body weight gain (BWG) and reduced feed conversion ratio (FCR) from 1 to 21 d (P < 0.05), as well as increased BWG from 1 to 42 d (P < 0.05). Serum 25-OH-D3 levels at 21 and 42 d were increased with 25-OH-D3 (P < 0.001). Phytase did not affect growth performance from 1 to 21 d, but a higher dose (2 000 FYT/kg) reduced feed intake and FCR from 22 to 42 d compared to 600 FYT/kg, also reducing FCR in the total period (P < 0.05). Expression of mechanistic target of rapamycin (mTOR) mRNA in breast muscle assessed at 42 d was enhanced with 2 000 FYT/kg (P < 0.001). Bone weight, bone contents of ash, Ca, and P, and bone breaking strength of tibia bone measured at 42 d were not affected by any dietary treatment. Although both additives are known to improve dietary Ca and P utilization, there were no detected additive or synergic effects. The results suggested that inclusion of 25-OH-D3 and phytase combined with regular vitamin D3 levels can help minimize losses of performance and bone mineralization of broilers fed Ca- and P-deficient diets. Furthermore, vitamin D status is refined with dietary 25-OH-D3 and potential improvements on breast meat yield can be obtained with a high phytase dose of 2 000 FYT/kg.

High dietary Mucuna pruriens utilis seed meal compromises growth performance, carcass traits, haemato-biochemistry, and meat quality of broilers.

Usage of soyabean meal (SBM) in broiler diets is economically and environmentally unsustainable thus necessitating investigation of alternative protein sources. Therefore, this study investigated effects of incremental inclusion levels of Mucuna pruriens utilis seed meal (MSM) for partial substitution of SBM in broiler diets. In a completely randomized design (CRD), 400day-old Ross 308 chicks were allotted to 5 iso-caloric-nitrogenous MSM-containing (0, 5, 10, 15, and 20%) dietary treatments. Each treatment was replicated 8 times, with each pen having 10 birds, during starter (d1 - 14), grower (d15 - 28), and finisher (d29 - 42) phases. Results showed that dietary MSM decreased feed intake (FI: quadratic: P < 0.001), body weight gain (BWG: linear: P < 0.001), and feed conversion efficiency (FCE: linear: P < 0.001) as it linearly decreased slaughter weight (SW: P < 0.001), hot carcass weight (HCW: P < 0.001), cold carcass weight (CCW: P < 0.001), dressing percentage (P < 0.001), and breast weight (P < 0.05). In contrast, dietary MSM linearly increased the weights of the liver (P < 0.01), proventriculus (P < 0.001), gizzard (P < 0.001), duodenum (P = 0.01), jejunum (P < 0.001), ileum (P < 0.001), caecum (P < 0.01), and colon (P < 0.01). Also, dietary MSM quadratically increased blood heterophils (P < 0.05) and alkaline phosphatase activity (P < 0.05) of the chickens whilst linearly increasing their serum amylase (P = 0.001) and lipase (P = 0.001) activities and linearly decreasing their serum symmetric dimethylarginine (SDMA: P = 0.001) and cholesterol (P < 0.05). Further, dietary MSM linearly decreased chicken breast meat ultimate pH (P < 0.05) whilst linearly increasing its cooking loss (P < 0.01), drip loss (P < 0.05) and shear force (P < 0.01). In conclusion, dietary MSM compromised growth performance, carcass characteristics, and meat quality of broilers as it increased the weights of their digestive-metabolic organs.

Effect of Azolla meal-based diet on growth performance, haematological profile and proximate composition of common carp (Cyprinus carpio) fry

Optimising the cost of nutrients in fish diets is crucial for aquaculture production, as feed accounts for 50% of operational expenses in intensive aquaculture. The rising demand for mustard oil cake (MOC), a commonly used feed ingredient in Indian aquaculture, has led to a significant increase in its price due to its diverse applications. Azolla (Azolla pinnata), a free-floating freshwater plant, has attracted researchers in fish feed formulation due to its rich nutrient profile. The present study was conducted to evaluate the effects of replacement of MOC with Azolla meal in the diet of common carp (Cyprinus carpio) fry. Pelleted feed was formulated with Azolla meal replacing MOC at levels of 0, 10, 20, 30 and 40% and fed to fish. Growth performance, feed conversion ratio (FCR), haematological parameters and proximate composition in fish carcass were assessed after 90 days of experimental feeding. Simultaneously, a control feed without supplementing of Azolla meal was also prepared. Fish were fed daily with the experimental diets at 8, 6 and 4% of their body weight during the first, second and third months respectively, in the morning hours (10:00 hrs). Principal component analysis (PCA) was performed to assess the effect of formulated diets on fish carcasses composition and haematological parameters. The results showed that replacing 30% of MOC with Azolla meal in the diet, led to significantly (p≤0.05) higher specific growth rate (SGR) and percentage weight gain and significantly (p≤0.05) lower feed conversion ratio (FCR) at this concentration. Fish survival rate ranged from 80.00 to 93.33% among different treatments. Further, significant (p≤0.05) differences were observed in both haematological parameters of fish and the proximate composition of fish carcass. among the different treatments. These findings suggest that MOC can be effectively replaced with 30% Azolla meal in the diet for rearing common carp fry to fingerling stage, without compromising the growth performance. Keywords: Aquaculture, Feed conversion ratio, Health status, Mustard oil cake, Principal component analysis, Specific growth rate, Survival

Effect of Dietary Benzoic Acid Supplementation on Growth Performance, Rumen Fermentation, and Rumen Microbiota in Weaned Holstein Dairy Calves

Supplementation with benzoic acid (BA) in animal feed can reduce feeds’ acid-binding capacity, inhibit pathogenic bacterial growth, enhance nutrient digestion, and increase intestinal enzyme activities. This study aimed to investigate the effects of different doses of BA on the growth performance, rumen fermentation, and rumen microbiota of weaned Holstein dairy calves. Thirty-two Holstein calves at 60 days of age were randomly assigned into four groups (n = 8): a control group (fed with a basal diet without BA supplementation; CON group) and groups that were supplemented with 0.25% (LBA group), 0.50% (MBA group), and 0.75% (HBA group) BA to the basal diet (dry matter basis), respectively. The experiment lasted for 42 days, starting at 60 days of age and ending at 102 days of age, with weaning occurring at 67 days of age. Supplementation with BA linearly increased the average daily gain of the weaned dairy calves, which was significantly higher in the LBA, MBA, and HBA groups than that in the CON group. The average daily feed intake was quadratically increased with increasing BA supplementation, peaking in the MBA group. Supplementation with BA linearly decreased the feed-to-gain (F/G) ratio, but did not affect rumen fermentation parameters, except for the molar proportion of butyrate and iso-butyrate, which were linearly increased with the dose of BA supplementation. Compared with the CON group, the molar proportions of iso-butyrate in the LBA, MBA, and HBA groups and that of butyrate in the HBA group were significantly higher than those in the CON group. Supplementation with BA had no significant effect on the alpha and beta diversity of the rumen microbiota, but significantly increased the relative abundances of beneficial bacteria, such as Bifidobacterium, and reduced those of the harmful bacteria, such as unclassified_o__Gastranaerophilales and Oscillospiraceae_UCG-002, in the rumen. Functional prediction analysis using the MetaCyc database revealed significant variations in the pathways associated with glycolysis across groups, including the GLYCOLYSIS-TCA-GLYOX-BYPASS, GLYCOL-GLYOXDEG-PWY, and P105-PWY pathways. In conclusion, BA supplementation improved the composition and function of rumen microbiota, elevated the production of butyrate and iso-butyrate, and increased the growth performance of weaned Holstein dairy calves.

Effects of passion fruit peel (Passiflora edulis) pectin and red yeast (Sporodiobolus pararoseus) cells on growth, immunity, intestinal morphology, gene expression, and gut microbiota in Nile tilapia (Oreochromis niloticus)

This study explores the effects of dietary supplementation with passion fruit peel pectin (Passiflora edulis) and red yeast cell walls (Sporidiobolus pararoseus) on growth performance, immunity, intestinal morphology, gene expression, and gut microbiota of Nile tilapia (Oreochromis niloticus). Nile tilapia with an initial body weight of approximately 15 ± 0.06 g were fed four isonitrogenous (29.09–29.94%), isolipidic (3.01–4.28%), and isoenergetic (4119–4214 Cal/g) diets containing 0 g kg−1 pectin or red yeast cell walls (T1 - Control), 10 g kg−1 pectin (T2), 10 g kg−1 red yeast (T3), and a combination of 10 g kg−1 pectin and 10 g kg−1 red yeast (T4) for 8 weeks. Growth rates and immune responses were assessed at 4 and 8 weeks, while histology, relative immune and antioxidant gene expression, and gut microbiota analysis were conducted after 8 weeks of feeding. The results showed that the combined supplementation (T4) significantly enhanced growth performance metrics, including final weight, weight gain, specific growth rate, and feed conversion ratio, particularly by week 8, compared to T1, T2, and T3 (P < 0.05). Immunological assessments revealed increased lysozyme and peroxidase activities in both skin mucus and serum, with the T4 group showing the most pronounced improvements. Additionally, antioxidant and immune-related gene expression, including glutathione peroxidase (GPX), glutathione reductase (GSR), and interleukin-1 (IL1), were upregulated in the gut, while intestinal morphology exhibited improved villus height and width. Gut microbiota analysis indicated increased alpha and beta diversity, with a notable rise in beneficial phyla such as Actinobacteriota and Firmicutes in the supplemented groups. These findings suggest that the combined use of pectin and red yeast cell walls as prebiotics in aquaculture can enhance the health and growth of Nile tilapia, offering a promising alternative to traditional practices. Further research is needed to determine optimal dosages for maximizing these benefits.

Growth performance of critically endangered Hypselobarbus pulchellus in biofloc system: Influence of carbon sources on immune response, enzyme and antioxidant activity

We investigated the effect of various carbon sources on the production performance of critically endangered Hypselobarbus pulchellus in biofloc system. The experimental setup comprised four biofloc treatment groups with various carbon sources (jaggery, tapioca, rice and corn flour) and a control group. Healthy early fry (0.0068 g) was randomly stocked at 100 individuals per m3 into 15 circular fibre reinforced plastic (FRP) tanks (1000 l) and raised for 90 days. All the tested carbon sources significantly influenced weight gain, weight gain (%) and specific growth rate (SGR), with the jaggery treatment displaying the best growth performance (p&lt;0.05). Fingerling survival rates varied from 93 to 95.67% (p&gt;0.05). Compared to the control, the biofloc groups had significantly lower concentrations of nitrogen compounds, specifically total ammonia nitrogen, nitrite and nitrate concentrations were significantly lowered (0.29, 0.35 and 1.32 mg l-1, respectively) in jaggery treatment (p&lt;0.05). In addition, the treatment using jaggery had a higher amount of plankton biomass and an abundance of the Bacillariophyceae group (80%). All biofloc groups displayed enhanced immune and antioxidant activity compared to the control. The jaggery treatment had elevated levels of lysozyme activity than other treatments (p&lt;0.05). Furthermore, fingerlings raised in BFT treatments had significantly higher amylase, protease and lipase activity (p&lt;0.05). Overall, this study’s findings suggest that the addition of various carbon sources significantly improves the production performance, with jaggery as the best carbon source for critically endangered H. pulchellus fingerling production in biofloc system to ensure sustainability. Keywords: Antioxidant activity, Fingerling, Heterotrophic bacteria, Jaggery, Specific growth rate, Sustainability

Effect of different energy and protein levels on growth performances and carcass yields of Sonali chicken

This study evaluated how varied energy and protein levels affect the growth and carcass traits of Sonali chickens. A 63-day experiment was conducted on 400-day-old Sonali chicks that were raised straight. The chicks were split into four groups of 100 birds apiece, which were then further separated into four subgroups of 25 birds each. The treatment groups were: T1 (2900 kcal/kg ME, 20% CP for starter and 3000 kcal/kg ME, 19% CP for grower); T2 (2900 kcal/kg ME, 21% CP for starter and 3000 kcal/kg ME, 20% CP for grower); T3 (2950 kcal/kg ME, 20% CP for starter and 3050 kcal/kg ME, 19% CP for grower) and T4 (2950 kcal/kg ME, 21% CP for starter and 3050 kcal/kg ME, 20% CP for grower) group. Sonali chicks were fed on starter diets from day old to 5 weeks of age and grower diets from 6 to 9 weeks of age. Results revealed that body weight was significantly (P&lt;0.05) higher in the group having 2950 kcal/kg ME, 21% CP for starter and 3050 kcal/kg ME, 20% CP for grower at 9th weeks of age. In addition, FCR and total body weight gain showed significantly (P&lt;0.05) better in the high nutrition group compared to other treated groups. Dressing percentage was numerically and abdominal fat was significantly (P&lt;0.05) higher in the group having 2950 kcal/kg ME, 21% CP for starter and 3050 kcal/kg ME, 20% CP for grower compared to other groups. However, there were no significant differences (P&gt;0.05) in skin, head, leg, liver, heart, gizzard, breast meat, drumstick meat, wing meat and thigh bone weight in relation to body weight among different dietary groups. Furthermore, despite the higher feed costs, the high nutrition group had higher selling price and profit margins per bird than the low nutrition diet. So, taken together, it can be concluded that a diet with high energy and high protein increases body weight and body weight gain and gives better FCR. Moreover, higher nutrition diet improves dressing yield, abdominal fat percentage and profit margins than the low nutrition diet. It is suggested that provision of energy (2950 kcal/kg ME for starter and 3050 kcal/kg ME for grower) and protein (21% CP for starter and 20% CP for grower) in the diet could be a potential energy and protein level for better performances of Sonali chicken. Bangladesh Journal of Animal Science 53(3): 101-110, 2024

Dietary inclusion of white lupine seeds and their byproducts in rabbits can contribute to EU agricultural sustainability: a review

This review explores the potential of white lupin seeds (Lupinus albus) as a sustainable protein source for rabbit nutrition and examines their effects on growth performance, carcass traits, health status, milk yield, milk composition and nutrient availability. The dietary inclusion of white lupin seeds leads to comparable or superior growth, milk yield, milk composition, nutrient digestibility and digestive health of rabbits, as well as meat quality and carcass outcomes relative to traditionally used protein sources for feeding rabbits, such as soybean meal and sunflower meal. Studies also show that it is possible to use white lupin byproducts, such as the hull and bran, for rabbit diets, which can be convenient in terms of providing an adequate supply of lignocellulose and enhancing the sustainability of rabbit feed, promoting circular economy principles. The cultivation of white lupin can contribute to environmental sustainability by reducing greenhouse gas emissions and the use of synthetic fertiliser. Future research should focus on breeding improvements and comprehensive environmental assessments of white lupin seeds to maximise the benefits of white lupin for rabbit nutrition. These findings support the role of white lupin as a viable and eco-friendly alternative to traditional protein sources, such as soybean meal, which could support productivity and sustainability in rabbit farming.

Performance of the edible halophyte Cakile maritima under critical magnesium and potassium thresholds

In their natural biotope, plants are challenged with low nutrient availability which is one of the most important limiting factors for plant production. Nutrient limitation causes disruption in several metabolic pathways resulting in a decrease in plant growth and establishment. Such responses were mostly studied in glycophytes while in halophytes the data remained scare. In the present investigation, using Cakile maritima as a plant model for halophytes, we attempt to elucidate the behavior of this species under critical magnesium and potassium thresholds. Our data showed that low K or Mg supply (0.01 mM) reduced leaf number and biomass production in leaves, stems and roots while both parameters were improved at 0.05 mM Mg and K concentration before reaching an optimum at 0.25 mM Mg and 1 mM K, respectively. Several indices of K and Mg stress tolerance were reduced upon deficiency in both elements and were significantly improved by moderate K and Mg supply. Photosynthetic pigment content was reduced upon both deficiencies with the highest reductions recorded in plants suffering from severe Mg and K starvation. Increasing Mg and K supply resulted in better chlorophyll synthesis as reflected by the increase in chlorophyll stability index parameter (CSI). Furthermore, both deficiencies triggered oxidative damages as malondialdehyde content (MDA) and electrolyte leakage (EL) increased while membrane stability index (MSI) decreased under both deficiencies. Such results suggested that the cell redox homeostasis was altered when Mg and K were omitted from the nutrient solution. Interestingly, moderate and high Mg and K concentrations promoted C. maritima growth and reduced the oxidative damage caused by the lack of both elements in the external medium. Overall, C. maritima exhibited a typical halophytic behaviour, requiring less macroelements to express its growth performance when cultivated under critical magnesium and potassium thresholds.

Productive, internal organ and intestinal histomorphological characteristics of broiler chickens in response to dietary rapeseed meal: A meta-analysis.

The use of rapeseed as a source of protein in broiler chicken diets has been highlighted. However, there are inconsistent findings on the performance data of broiler chickens fed rapeseed meal (RSM). Therefore, this meta-analysis aimed to resolve the inconsistent findings on the effect of RSM on growth performance, carcass characteristics, internal organs, and intestinal histomorphology of broiler chickens, identify knowledge gaps and create new insights using published data. Fourteen studies on the topic were identified via a systematic search performed on bibliographic databases, and the data generated was analysed using OpenMEE software. A random-effects model was used, and effect sizes were presented as standardised mean difference (SMD) at a 95% confidence interval (CI). Sources of heterogeneity were evaluated using broiler strains, inclusion levels, processing methods, rearing phases and sex as moderators. In comparison with the controls, the results showed that RSM decreased feed intake (SMD = -0.29; 95% Cl: -0.41, -0.18; p < 0.001), average daily gain (SMD = -0.48; 95% Cl: -0.63, -0.32; p < 0.001), and liver weight (SMD = 1.24; 95% Cl: 0.78, 1.71; p < 0.001), but had no effect on feed conversion ratio (SMD = 0.10; 95% Cl: -0.05, 0.23; p = 0.19). Likewise, broiler chickens fed RSM had significantly reduced carcass yield, weights of thigh, abdominal fat and heart when compared with the control. Results indicate that duodenum villus height (DVH) and jejunum villus height (JVH)/crypt depth (CD) ratios were improved in broiler chickens fed RSM. Meta-regression revealed that the analysed moderators are significant predictors of feed intake, average daily gain and feed conversion ratio in broiler chickens. In conclusion, dietary RSM negatively influenced growth performance, liver weight and carcass characteristics in broiler chickens, but improved aspects of intestinal histomorphology traits. Therefore, innovative research on processing methods that will improve the feeding value of rapeseed meal in broiler chickens is recommended.

Supplementing pigeon grit with acidifier improves metabolism and the reproductive performance of breeding pigeons as well as the development of growth performance of squabs

ABSTRACT 1. This study evaluated the effectiveness of different types of acidifiers on reproductive performance, body weight loss and plasma biochemical indices of breeding pigeons as well as on growth performance, carcass characteristics, meat quality and plasma biochemical indices of squabs. 2. In a 45 d trial, 144 pairs of European white Mimas pigeons were selected and randomly divided into three experimental groups. Three groups of pigeons were fed plain pigeon grit (NC), pigeon grit supplemented with 5% single acidifier (SAG) and pigeon grit supplemented with 5% combined acidifiers (CAG). 3. Supplementing with SAG and CAG significantly increased the weight gain in male pigeons from 1-12 d of incubation. However, SAG and CAG had no significant effect on the feed intake of breeding pigeons during incubation, but significantly increased total feed intake of breeding pigeons during the lactation period. Breeder pigeons fed SAG and CAG had significantly higher egg-laying rate at 40 d. In addition, feeding SAG and CAG significantly increased growth rate and slaughter weight of squabs, but SAG reduced the diameter of pectoral muscle fibres. Biochemical indices showed that feeding SAG and CAG improved metabolism and increased the liver function of breeder pigeons and squabs. 4. In conclusion, supplementing pigeon grit with acidifiers increased feed intake of breeding pigeons during lactation, protected liver function, enhanced reproductive performance and promoted the growth and development of squabs.