Growth Hormone Gene Expression Research Articles

Nutritional synergy: optimizing growth in Siruvidai chicken via diverse dietary energy and protein strategies and gene expression analysis - brooder phase.

Nutrient supply regulates overall body growth directly or indirectly through its influence on regulatory factors optimizing nutrient requirements becomes crucial before embarking on genetic improvements. Hence this study addresses this gap by evaluating the effect of feeding varying energy and crude protein levels on growth performance and gene expression related to the growth of indigenous Siruvidai chicken from 0 to 12 weeks. A 360-day-old straight-run Siruvidai chick were randomly distributed into six experimental groups with three replicates of each 20 chicks. The birds were fed corn-soy-based diets formulated with two levels of energy (2500 and 2700kcal ME/kg) each with three levels of crude protein (16, 18, and 20%) during the brooder stage (0-12 weeks) in 2 × 3 factorial design. Results revealed that there was no significant effect on the energy and protein interaction levels on average feed intake, body weight gain and feed conversion ratio in Siruvidai chicken at 12 weeks. The results showed significantly (P < 0.05) lower feed intake in 18% protein fed groups and significantly (P < 0.01) lower feed intake in higher energy 2700kcal ME/kg fed groups. A better feed conversion ratio (4.06 and 4.21) was observed on the effect of protein levels in bird diets with 18% and 20% protein fed groups. The Growth Hormone (GH) and Myostatin (MSTN) gene expression were significantly (P < 0.01) higher in 16% CP and 2500kcal ME/kg in hepatic tissue. The high protein and low energy diet up-regulated the Insulin-like Growth Factor-1 (IGF-1) gene expression in hepatic tissue. The study concluded that Siruvidai chicken fed with 18% crude protein and 2500kcal ME/kg is optimum for 0-12 weeks of age.

The effect of fishmeal replacement with organic acid fermented black soldier fly (Hermetia illucens) larvae meal on growth, nutrient utilization, metabolic enzyme activity, antioxidant status and immunity in Pangasius (Pangasianodon hypophthalmus)

Black soldier fly (Hermetia illucens) larvae meal is emerging as an alternative protein source and good substitute of fishmeal (FM). In an 8-week feeding trial, three hundred pangasius (Pangasianodon hypophthalmus,7.44 ± 0.01 g) fingerlings were randomly allocated over five treatments in triplicate tanks and fed five isoprotein (CP, 35%) and isolipidic (CL, 10%) diets formulated by replacing 0% (FBSFL0), 25% (FBSFL25), 50% (FBSFL50), 75% (FBSFL75) and 100% (FBSFL100) FM with organic acid (formic acid) fermented black soldier fly larvae meal (FBSFL). The inclusion of FBSFL did not affect growth, feed conversion ratio, nutrients utilization and survival rate of pangasius even when FM was completely replaced. The pangasius body protein content increased significantly (P < 0.05) with increasing FBSFL level in the diets while, body lipid content was unaffected (P > 0.05). The haematological indices were not (P > 0.05) affected with the FBSFL inclusion levels. Significantly (P < 0.05) higher and alike protease activity was recorded in FBSFL50, FBSFL75, and FBSFL100 groups. However, activity of amylase and lipase were similar among treatments. The liver antioxidant enzymes (SOD, catalase, and GST) did not show significant (P > 0.05) difference among the treatments. However, pangasius fed with FBSFL75 and FBSFL100 showed significantly higher and similar total antioxidant capacity (T-AOC). The FBSFL in the diet of pangasius did not affect the liver metabolic enzyme (MDH, G-6-PDH and GDH) activities. Relative gene expression of growth hormone (GH1) did not substantially differ among the groups (P < 0.05). No differences were observed in the immune gene expressions of complement (C3) and interleukin-1β (IL-1β) but the expression level of transferrin was up-regulated significantly (P < 0.05) in FBSFL25 group. No damage was observed in hepatic tissues in histomorphometry examination due to the inclusion of FBSFL. The study concludes that formic acid fermented BSFL can be employed as a complete substitute for FM in the pangasius diet, offering additional health benefits without any adverse effects.

The effects of nano-curcumin on growth performance, feed utilization, blood biochemistry, disease resistance, and gene expression in European seabass (Dicentrarchus labrax) fingerlings

Phytochemicals are used in fish farming to reduce stress and combat diseases during intensification. Recently, nanotechnology has represented a paradigm shift in the aquatic feed industry to improve the solubility, availability, and efficacy of phytochemicals. The purpose of this research was to investigate the effects of dietary supplementation with nano-curcumin (CUNE) on the growth, feed utilization, body composition, blood biochemistry, antioxidant status, disease resistance to Vibrio parahaemolyticus (V. parahaemolyticus), and the expression of insulin-like growth factor 1 (IGF-1), growth hormone (GH), interleukin-10 (IL-10), and interlukin-1β (IL-1β) genes in European Seabass (Dicentrarchus labrax) fingerlings. Fish (6.02±0.01) were randomly divided into four equal groups and fed varying levels of CUNE: 0 (CUNE0), 50 (CUNE1), 60 (CUNE2), and 70 mg/kg (CUNE3) of nano-curcumin for 56 days, respectively. The inclusion of dietary CUNE significantly improved the growth indices (final body weight and weight gain, and specific growth rate) and feed utilization (improved feed intake and lower FCR) of European seabass fingerlings (p<0.05). However, CUNE inclusion had no significant effect on body composition including the percentages of dry mater, crude protein, crude lipid, and ash (p>0.05). All CUNE groups established an enhancement in blood hematology in a dose-dependent manner, with CUNE3 demonstrating the highest values. CUNE supplementation (70 mg/kg diet) produced the highest levels of total protein, albumin, globulin, and triglycerides, as well as the lowest levels of glucose, and hepatic enzymes (ALT, AST, and ALP; p<0.05) compared to other groups. Furthermore, the CUNE-supplemented groups showed significant improvements in superoxide dismutase, catalase, and glutathione peroxidase, while reducing malondialdehyde (p<0.05). Additionally, the consumption of CUNE increased the expression of IGF-1, GH, and IL-10 genes in a dose-dependent manner (p<0.05). Interestingly, fish fed 70 mg of CUNE in their diets had lower expression of the IL-1β gene compared to the other groups (p<0.05). When the fish were challenged with V. parahaemolyticus, the addition of CUNE in their diets resulted in reduced mortality rates. Therefore, nano-curcumin could be considered as a natural feed additive to promote growth, feed utilization, and bacteria resistance via supporting antioxidant status, serum metabolites, and the regulation of GH, IL-10, and IGF-1 in the hepatic tissues of European seabass fingerlings.

Nucleotides supplementation (Nucleoforce fish™) in Caspian roach (Rutilus caspicus) diet: Growth performance, skin mucosal immune response, and resistance to salinity stress

In this study, the growth, epidermal mucosal immunity, expression of growth-related genes, cross-protection, and resistance to salinity stress of Caspian roach were scrutinized in response to dietary levels of nucleotides (NT). Accordingly, 1200 fish (0.51 ± 0.01 g) were fed ad libitum with a basal diet (38.88 % crude protein and 10.04 % crude lipid in dry basis) containing incremental levels of NT at 0 (NT-0; control), 0.3 g kg−1 (NT-0.3), 0.6 g kg−1 (NT-0.6), and 1.2 g kg−1 (NT-1.2) for 8 weeks in triplicates. The growth performance was significantly increased in the fish fed with NT-0.6 and NT-1.2 diets compared to the control group (p < 0.05). A significant elevation in the growth hormone and insulin-like growth factor-I gene expression was recorded in NT-added groups at 0.6 and 1.2 g kg−1 compared to the control group (p < 0.05). In contrast to the control group, feeding on NT-0.6 and NT-1.2 diets had a remarkable effect on the skin mucus soluble protein and immunoglobulin levels (p < 0.05). After the feeding trial, we examined how salinity stress (15 g/l salinity) lonely and salinity stress under non-lethal thermal shock (+10 °C) affected heat shock protein (HSP70). Then, the mRNA expression of HSP70 gene from the gill was analyzed at 0, 2, 8, and 24 h post-challenge tests. The HSP70 gene expression level was approximately up-regulated more than 2-fold in NT-6 and NT-1.2 treatments compared to the control group under the salinity stress. Altogether, this research represents that the addition of NT at 0.6 and 1.2 g kg−1 in Caspian roach diet can improve overall performance and resistance to salinity stress.

Source diversity of Artemia enrichment boosts goldfish (Carassius auratus) performance, β-carotene content, pigmentation, immune-physiological and transcriptomic responses

This study aimed to assess the impact of spirulina and/or canthaxanthin-enriched Artemia on the goldfish (Carassius auratus) growth, pigmentation, blood analysis, immunity, intestine and liver histomorphology, and expression of somatolactin (SL) and growth hormone (GH) genes. Artemia was enriched with spirulina and/or canthaxanthin for 24 h. Goldfish (N = 225, 1.10 ± 0.02 g) were tested in five experimental treatments, three replicates each: (T1) fish fed a commercial diet; (T2) fish fed a commercial diet and un-enriched Artemia (UEA); (T3) fish fed a commercial diet and spirulina-enriched Artemia (SEA); (T4) fish fed a commercial diet and canthaxanthin-enriched Artemia (CEA); and (T5) fish fed a commercial diet and spirulina and canthaxanthin-enriched Artemia (SCA) for 90 days. The results showed that the use of spirulina and/or canthaxanthin increased performance, β-carotene content and polyunsaturated fatty acids of Artemia. For goldfish, T5 showed the highest growth performance, β-carotene concentration and the lowest chromatic deformity. T5 also showed improved hematology profile, serum biochemical, and immunological parameters. Histomorphology of the intestine revealed an increase in villi length and goblet cells number in the anterior and middle intestine, with normal liver structure in T5. SL and GH gene expression in the liver and brain differed significantly among treatments with a significant increase in enriched Artemia treatments compared to T1 and T2. In conclusion, the use of spirulina and/or canthaxanthin improved performance of Artemia. Feeding goldfish spirulina and/or canthaxanthin-enriched Artemia improved performance, β-carotene content, pigmentation, health status and immune-physiological response.

THU157 Epigenetic Regulation Of Genes Involved In The Signaling Cascade Of The GH Axis - IGF1 And Insulin. Implication In Children Postnatal Growth

Abstract Disclosure: L. Zoff: None. F. Garcia: None. G. Aschettino: None. G. Veneruzzo: None. M.C. Mattone: None. N. Perez Garrido: None. M. Juanes: None. N.I. Saraco: None. C. Alonso: None. G. Guercio: None. A. Belgorosky: None. M.S. Baquedano: None. Growth is influenced by genetic, nutritional, environmental, and hormonal factors, but it proceeds in a predictable pattern characterized by a constant growth deceleration between childhood and adolescence. This growth deceleration is coordinated in tissues and organs in order to maintain body proportions. Growth hormone (GH)/ insulin-like growth factor type 1 (IGF1) axis and insulin are crucial stimulators of growth, cell proliferation and metabolism. However, their levels do not change with age in a pattern that would explain the prepubertal decline in growth rate. DNA methylation represents a fundamental epigenetic mark that is associated with transcriptional repression during development. We hypothesize that the postnatal growth pattern could be orchestrated by epigenetic mechanisms. In order to analyze age related physiological changes, we evaluated promoter methylation in the GHR, IGF1R and INSR genes in peripheral blood from 40 healthy children of both sexes (females (F) n=21 and males (M) n=19), between 3 and 15 years old by using targeted deep-amplicon bisulfite sequencing on a MiSeq system. Sequencing libraries of 4 promoter CpG rich regions for GHR, 3 for IGF1R and 5 for INSR (104, 103 and 141 CpG sites, respectively) were analyzed for mean methylation values of all CpG sites using amplikyzer2 software. The results would suggest a sexual dimorphism in the epigenetic regulation of GH, IGF1 and insulin receptors gene expression. A significant negative correlation between GHR methylation and age was observed in both sexes (Multiple Spearman correlation, p&amp;lt;0.05), but in different GHR promoter regions. Specifically, a decrease in themethylation levels with age were detected in CpG-8, CpG+183 and CpG+243 in F; and in CpG+343, CpG+346, CpG+385, CpG+391, CpG+407 and CpG+487 in M. In contrast, in the IGF1R promoter region, a positive correlation was observed exclusively in F, between mean methylation levels and age in CpG-51, CpG-43, CpG-41, CpG-23, CpG-17, CpG-15, CpG-13, CpG-11, and CpG-9, p&amp;lt;0.05. Male-specific positive correlation between INSR promotermethylation values and age were found in CpG-768, CpG+10, CpG+31, CpG+87, CpG+95, CpG+163, CpG+199, CpG+206, CpG+238, CpG+700, CpG+815 and CpG+900, p&amp;lt;0.05.Taking together, our findings are in agreement with the hypothesis that age-associated DNA promoter methylation changes could be involved in the physiological growth pattern. Finally, the observed sexual dimorphism suggests age- and sex-dependent regulatory mechanisms for normal growth. Presentation: Thursday, June 15, 2023

Effect of Four Functional Feed Additives on Growth, Serum Biochemistry, Antioxidant Capacity, Gene Expressions, Histomorphology, Digestive Enzyme Activities and Disease Resistance in Juvenile Olive Flounder, Paralichthys olivaceus.

An 8-week feeding trial was executed to evaluate the efficacy of four functional feed additives in replacing antibiotics in juvenile olive flounder, Paralichthys olivaceus, fed with a low-fish-meal diet. A basal diet without feed additives was used as a control (CON); other diets were formulated by supplementing 0.50% taurine (TW), 0.30% peptide (PT), 0.23% mineral water (MW), 0.35% yeast-extracted nucleotides (GRO), 0.35% GRO + 0.50% taurine (GROTW), 0.35% GRO + 0.30% peptide (GROPT) and 0.35% GRO + 0.23% mineral water (GROMW) into the basal diet; in addition, one diet was supplemented with oxytetracycline (OTC) at 0.5% as a positive control. Triplicate groups of 25 fish with an average weight of 5.15 ± 0.06 g (mean ± SD) were fed one of the nine experimental diets. At the end of the feeding trial, the weight gain, specific growth rate and protein efficiency ratio of fish fed the GRO, GROMW, GROPT and GROTW diets were significantly higher than those of fish fed the CON diet (p < 0.05). The feed efficiency of fish fed the GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the TW and OTC diets. However, the survival, hepatosomatic index, viscerosomatic index and condition factor of fish, as well as their whole-body proximate composition, were not significantly affected by the experimental diets (p > 0.05). The serum glutamic pyruvic transaminase of fish fed the GROPT diet was significantly lower than that of fish fed the CON diet. However, glutamic oxaloacetic transaminase, glucose and total protein were not significantly affected by the experimental diets (p > 0.05). The serum superoxide dismutase activity of fish fed the PT, TW, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON diet. The lysozyme activity of fish fed the PT, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON and OTC diets. The myeloperoxidase activity of fish fed the TW, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON, PT and MW diets (p < 0.05). The flounder growth hormone gene expression of fish fed the TW, GRO, GROMW, GROPT, GROTW and OTC diets was significantly higher than that of fish fed the CON, PT and MW diets (p < 0.05). The interleukin 1β and interleukin 10 gene expressions of fish fed the GRO, GROMW, GROPT and GROTW diets were significantly higher than those of fish fed the CON, PT, TW and MW diets (p < 0.05). Intestinal histology showed a significantly higher villi length for fish fed the GRO, GROMW, GROPT and GROTW diets compared to that of fish fed the CON diet (p < 0.05). Digestive enzyme activities such as trypsin activity were significantly higher in fish fed the GROMW, GROPT and GROTW diets than those in the rest of the diet groups (p < 0.05). Amylase activity in fish fed the MW, GRO, GROMW, GROPT, GROTW and OTC diets was significantly higher than that of fish fed the PT, TW and CON diets (p < 0.05). On the other hand, the lipase activity of fish fed the TW, GRO, GROMW, GROPT and GROTW diets was significantly higher than that of fish fed the CON, PT, MW and OTC diets (p < 0.05). The cumulative survival rate of fish fed the PT, GROTW, GROPT and GROMW diets was significantly higher than that of fish fed the CON, TW and MW diets after thirteen days of the challenge testing. Overall, the results demonstrate that the GRO, GROMW, GROPT and GROTW diets could be beneficial feed additives to replace antibiotics in juvenile olive flounder fed low-fish-meal diets.

Performa Pertumbuhan dan Ekspresi Gen Hormon Pertumbuhan Sidat (Anguilla bicolor bicolor) Stadia Elver Yang diberi Pakan Mengandung Kromium Pikolinat

The administration of chromium picolinate (Cr-Pic) is expected to positively influence the growth of eel (Anguilla bicolor) and the expression of the growth related gene. The purpose of this research was to study the effect of chromium picolinate (Cr-Pic) on the growth performance and expression of growth hormone encoding gene of eel (Anguilla bicolor), a species of fish that is in the process of domestication. The experiment consisted of four treatments: without Cr-Pic (P0), with Cr-Pic of 1 mg / kg of feed (P1), 2 mg / kg of feed (P2), and 3 mg / kg of feed (P3). Eel growth performance was analyzed based on absolute and daily growth rates. Observation of the level of growth hormone (GH) gene expression was performed using real-time RT-PCR method. The results showed that administration of Cr-Pic did not significantly increase eel growth rate. The expression level of growth hormone genes in eel fed 2 and 3 mg Cr-Pic / kg was higher than the expression level of this gene in eel fed without Cr-Pic. The results showed that the level of growth hormone expression did not appear to be related to growth rate of the eel.

The growth hormone gene polymorphism and its relationship to performance and carcass features in Egyptian Awassi lambs

The main purpose of the existing experiment was to assess the allelic and genotypic polymorphisms of the Growth hormone (GH) gene and its correlation with growth indices, efficiency of consumed feed, some body indices and carcass traits of the Egyptian Awassi sheep. Forty Egyptian Awassi male lambs were selected for their growing indices (post-weaning daily gain, marketing weight, and weaning weight), feed efficiency (consumed feed and of consumed feed), body conformational indicators (skeletal muscle index, relative body index, body mass index, and body index), and carcass features (dressing %, hot carcass weight, fore-legs %, neck %, loin %, ribs %, abdominal fat %, Tail % and hind-legs %). The polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP) tool was applied to detect the genotypic and allelic GH gene polymorphisms properties. The PCR-RFLP analysis identified three main genotypes (AA, AB and BB) and two main alleles (A and B). The GH genotype (AA or AB) exhibited moderate significant influence (P < 0.05) on marketing weight, Loin% and Tail%. Also, genotype (AB or BB) of expressed GH gene significantly (P < 0.01) influence on consumed feed, post-weaning daily gain, neck% and body mass index, whereas, it had no influence on the phenotypic values of the other characteristics investigated. The presence of the A allele in the genotype was markedly associated (P < 0.01) with consumed feed, body mass index and post-weaning daily growth; conversely, the presence of the B allele in the genotype was significantly related (P < 0.05) with marketing weight, loin %, and tail %. While, GH gene expression was revealed to be highly significant (P < 0.01) in relation to post-weaning daily growth, feed intake, and neck %. According to the findings, determining the associations between GH gene variation and growth, efficiency of consumed feed, body measurements, and carcass features of Egyptian Awassi sheep and applying marker assisted selection with the GH gene to improve these traits is warranted and will be of significant economic value to sheep production.

Environment and genotype predict the genomic nature of domestication of salmonids as revealed by gene expression.

Billions of salmonids are produced annually by artificial reproduction for harvest and conservation. Morphologically, behaviourally and physiologically these fish differ from wild-born fish, including in ways consistent with domestication. Unlike most studied domesticates, which diverged from wild ancestors millennia ago, salmonids offer a tractable model for early-stage domestication. Here, we review a fundamental mechanism for domestication-driven differences in early-stage domestication, differentially expressed genes (DEGs), in salmonids. We found 34 publications examining DEGs under domestication driven by environment and genotype, covering six species, over a range of life-history stages and tissues. Three trends emerged. First, domesticated genotypes have increased expression of growth hormone and related metabolic genes, with differences magnified under artificial environments with increased food. Regulatory consequences of these DEGs potentially drive overall DEG patterns. Second, immune genes are often DEGs under domestication and not simply owing to release from growth-immune trade-offs under increased food. Third, domesticated genotypes exhibit reduced gene expression plasticity, with plasticity further reduced in low-complexity environments typical of production systems. Recommendations for experimental design improvements, coupled with tissue-specific expression and emerging analytical approaches for DEGs present tractable avenues to understand the evolution of domestication in salmonids and other species.

Dietary Supplementation of Silybum marianum Seeds Improved Growth Performance and Upregulated Associated Gene Expression of Muscovy Ducklings (Cairina moschata).

The effect of feeding on diets supplemented with Silybum marianum L. dry seeds (SMS) on growth performance, mortality percentage, biochemical parameters, the expression profile of related genes, and genotoxic effect in Muscovy ducklings was evaluated during a brooding period of 4 weeks. Two hundred and forty one-day-old Muscovy ducks were randomly assigned to four treatment groups (60 ducklings/group), the first group fed on basal diet with no additives (control), and the second (4 g kg-1), third (8 g kg-1), and fourth (12 g kg-1) groups fed the basal diet supplemented with 0, 4, 8, and 12 g kg-1 diet SMS, respectively. A substantial improvement in live body weight (LBW), body weight gain (BWG), and growth rate (GR), and a decrease in feed conversion ratios (FCR) and mortality rate were shown in ducks fed a diet supplemented with either 8 g kg-1 or 12 g kg-1 SMS compared to the other groups. Relevant improvements in liver function, oxidative stress markers, purinergic cell energy, and brain appetite were recorded on ducklings fed diets supplemented with SMS. Moreover, diets which included 8 or 12 g kg-1 SMS positively upregulated the expression of growth hormone gene (GH) and antioxidant genes (SOD1, SOD2, and CAT). These results are consistent with the increase in liver activity SOD and CAT enzymes, resulting in less DNA fragmentation. Consequently, all the aforementioned improvements in biochemical parameters and gene expression profiling may explain the superiority of the treated ducklings compared with the control group. Conclusively, the SMS could be used as a natural feed additive to promote health status and improve the growth performance of small grower ducks during the brooding period.

Expression of the Growth Hormone Gene during Early Development of Tiger Shovelnose Catfish (Pseudoplatystoma Fasciatum Linnaeus, 1766)

The early development stage of fish is crucial in fish farming, especially catfish species with cannibal characteristics, such as the Tiger Shovelnose Catfish (Pseudoplatystoma fasciatum Linnaeus 1766). Growth plays an essential role in fish’s life, which is influenced by the mechanism of growth hormone (GH). This study analyzed the level of growth hormone (GH) gene expression at several early developmental stages of Tiger Shovelnose Catfish. Samples were taken from an embryo, three days post hatched (dph) larvae to 60 dph juvenile. Isolation of mRNA was carried from the pituitary gland located at the head of the fish. Gene expression analysis was performed using RT-PCR method that compared GH/b-actin genes from band thickness. The results of the analysis showed the highest expression at 60 dph juvenile. The most significant increase in GH gene expression occurred from the egg to three dph larvae (P &lt; 0.05), then decreased to 20 dph juvenile. The increased phenotypic growth was seen from the increased length and weight at 45 dph juveniles. This indicates the amount of growth hormone released at the juvenile stage of 20 dph, thus triggering rapid growth in the next stage at 45 dph juvenile. Growth hormones can act as growth biomarkers in Tiger Shovelnose Catfish. The novelty of this study was to determine the level of GH gene expression in Pseudoplatystoma fasciatum ornamental fish as the object of research. Suggestions for further research to explore genes related to growth mechanisms through transcriptomic and proteomic technologies.

Can dietary phytogenic mixture improve performance for growth, digestive enzyme activity, blood parameters, and antioxidant and related gene expressions of Nile tilapia, Oreochromis niloticus?

The form of dietary phytogenic inclusion and its physiological causal mechanisms for growth promotion and immune stimulation in fish remain unknown. The study examined the effects of dietary phytogenic mixture extracted from lemon (Citrus limon), onion (Allium cepa), and garlic (Allium sativum) (LOG) on Nile tilapia performance, digestive enzymes, haemato-biochemical indices, oxidative stress, and associated gene expression for 70 days. In this experiment, diets were supplemented with 0, 10, 20, and 30 ml LOG kg−1 in isonitrogenous and isoenergetic diets and fed to tilapia with an average initial body weight (4.23 ± 0.09 g). Compared to the control diet, the dietary LOG at 20 ml kg−1 elicited the highest final body weight (FBW, 35.50 g fish−1), weight gain (WG, 31.2 g fish−1), specific growth rate (SGR, 3.02%, day fish−1), and survival rate (99.33%). Significant quadratic differences in chymotrypsin, trypsin, amylase, and lipase were shown with increasing LOG supplementation. There was a quadratic response in hematology parameters of fish with increasing LOG levels. Significant linear decreases in ALT, AST, cholesterol, and triglyceride were shown with the increased LOG inclusion in the diets. A polynomial correlation in total protein, albumin, and globulin was found under different inclusion levels of LOG while significant quadratic increases in SOD, CAT, and Gpx and significant quadratic decrease in MDA was found with increasing LOG supplementation. The IGM-2, SOD, and CAT gene expressions were quadratically improved; the highest relative expression was obtained by fish received 20 ml LOG kg−1 diet. Growth hormone gene expression was quadratically modulated in the liver and pituitary of fish fed diverse doses of dietary LOG compared with the control. The phytogenic of LOG at 20 ml kg−1 elicited the best tilapia performance and hematological indices, increased antioxidant and digestive enzyme activities, and gene expressions of growth, immunoglobulin and superoxide dismutase.

Different expression of LHR, PRLR, GH and IGF1 during testicular development of yak

AbstractLuteinizing hormone receptor (LHR), prolactin receptor (PRLR), growth hormone (GH) and insulin‐like growth factor 1 (IGF1) have been shown to be key regulators of germ cell development. However, the role of LHR, PRLR, GH and IGF1 in the development of yak testis remains unclear. In this study, we aimed to describe and compare gene expression and protein localization of LHR, PRLR, GH and IGF1 in the development of yak testes. Testes were collected from 6, 24, 36 and 72 months yak, and the kidney, liver, testicular, lung, skeletal muscle, heart and spleen tissues were collected from 36 months yak. The quantitative real‐time PCR (qRT‐PCR) results showed that the expression of these four genes was widely expressed in kidney, liver, testicular, lung, skeletal muscle, heart and spleen, while the LHR and PRLR were highly expressed in the kidney, skeletal muscle and testis, and higher levels of GH and IGF were expressed in spleen and testis. Moreover, the mRNA expression of these genes in adults was higher than in pre‐pubertal yak. In the testis, the LHR‐, PRLR‐, GH‐ and IGF1‐positive signals were detected in the Leydig cells of the 6 months, while the intense positive signals were discovered in Leydig cells, spermatogonia and spermatocytes of the 36 and 72 months. Thus, LHR, PRLR, GH and IGF1 may be involved in the development of spermatids and spermatocytes, and in the regulation of spermatogonia proliferation and Leydig cell function.

Acute and chronic effects of cortisol on milk yield, the expression of key receptors, and apoptosis of mammary epithelial cells in Saanen goats

Cortisol (CORT) induces mammary development in late gestation and is fundamental to the differentiation of mammary epithelial cells and lactogenesis. The objective of this study was to investigate the relationship between CORT, insulin, prolactin, growth hormone, and insulin-like growth factor-1 in milk as well as the effect of CORT on the expression of receptors of insulin (INSR), prolactin (PRLR), growth hormone (GHR); we also studied the insulin-like growth factor-1 (IGF1R), glucocorticoid (NR3C1), mineralocorticoid (NR3C2), B-cell lymphoma 2 (BCL2), BCL-2-like protein X (BAX) genes, and the apoptosis rate of mammary epithelial cells of lactating Saanen goats in vivo and in vitro. The following experiments were conducted: (1) comparing hormone release in milk and blood after ACTH or a placebo administration; (2) evaluating the effect of acute CORT increases in mammary gland expression and milk yield in vivo; and (3) evaluating the effect of a chronic increase in CORT concentration in epithelial mammary cell apoptosis in vitro. In vivo, ACTH administration significantly increased CORT release but did not affect insulin, prolactin, growth hormone, and insulin-like growth factor-1 release in plasma and milk versus placebo. The results show also that a low CORT release after ACTH administration increased the expression of GHR and PRLR genes in the mammary tissue. Indeed, CORT release significantly increased the milk yield from goats subjected to ACTH versus goats subjected to the placebo. However, a higher amount of CORT added in vitro upregulated the NR3C1, GHR, PRLR, and BAX genes and downregulated the IGF1R and INSR genes, which could negatively modulate the apoptosis of mammary epithelial cells. Finally, the effect of CORT in vivo after ACTH administration demonstrated the increased expression of the PRLR and GHR genes, which may improve epithelial cell responsiveness and be associated with the positive effect of CORT observed on milk yield at mid-end lactation.

Selenium and Zinc Oxide Multinutrient Supplementation Enhanced Growth Performance in Zebra Fish by Modulating Oxidative Stress and Growth-Related Gene Expression.

Selenium and zinc are important dietary micronutrients having antimicrobial and antioxidant roles, thereby assisting in normal development, and an enhanced immune system. Supplementation of selenium and zinc for enhancing the growth performance and reproductive capacity in fish was explored in this study. Selenium nanoparticles (SeNPs) and zinc oxide nanoparticles (ZnONPs) were synthesized by high-energy ball milling (HEBM) using a 10-h dry milling technique at a 10:1 ball-to-powder ratio (BPR) and were premixed with basal feed followed by the administration to adult zebra fish (D. rerio) (2 months old) for 30 days. Growth analysis revealed that zebra fish fed with SeNPs + ZnONPs (2 mg/ kg, equimolar mixture) had significantly higher length and weight than only SeNP (2 mg/ kg) or ZnONP (2 mg/ kg) groups and control zebra fish (p < 0.05). The average length–weight relationships were assessed by estimating the condition factor (C), which was highest in the SeNP + ZnONP group (1.96), followed by a downward trend in SeNP (C = 1.15) and ZnONP (1.11) (p < 0.05). Relative gene expression of growth hormone and insulin-like growth factor-1 was significantly high in the SeNP + ZnONP group compared to other groups (p < 0.05), which indicated that combined administration of both the nanoparticles in basal feed enhanced the growth performance of zebra fish. Intracellular ROS generation was low in the combined group, followed by control, SeNP, and ZnONP groups, indicating higher concentrations of both nanoparticles, in particular, ZnONPs induced oxidative stress. Fecundity and the development of fertilized embryos were significantly high in the SeNP + ZnONP–treated zebra fish compared to only the SeNP- or ZnONP-treated group or control (p < 0.05). These findings indicated that supplementation of SeNP + ZnONP in basal feed could considerably improve the growth performance and development of zebra fish which could be exploited for enhancing aquaculture production.

Higher acclimation temperature affects growth of rohu (Labeorohita) through suppression of GH and IGFs genes expression actuating stress response.

Water temperature alone can affect the growth, metabolic rates and physiological responses of aquatic organisms. Our earlier study reported that higher temperature affects cellular and hemato-biochemical responses in rohu, Labeo rohita. In this backdrop, the present study assessed the effect of higher acclimation temperature on the regulatory mechanisms of growth and stress responses of juvenile L. rohita acclimatized in three temperature conditions (30°C, 33°C, and 36°C) for a period of 30 days. The relative expression of genes for growth hormone (GH), insulin-like growth factors (IGF-1 and IGF-2) and heat shock proteins (hsp70 and hsp90) were measured by real-time quantitative PCR. The results revealed that the highest acclimation temperature (36°C) significantly decreased the weight gain (WG) and specific growth rate (SGR), and increased the feed conversion ratio (FCR) compared to 30°C (control), while increased WG, SGR and lowered FCR were observed in fish reared at the intermediate temperature (33°C) compared to 30°C. Similarly, the GH gene expression in the pituitary was significantly decreased and increased at 36°C and 33°C, respectively as compared to 30°C. A significantly lower expression of IGF-1 and IGF-2, and higher expression of hsp70 and hsp90 were observed in the liver of fish at 36°C. The results of the present study indicate that although slightly elevated temperature promotes the growth of juvenile L. rohita, the higher acclimation temperature may induce stress response and impair growth performance by suppressing GH/IGF system.

LPXRFa and its receptor in yellowtail kingfish (Seriola lalandi): Molecular cloning, ontogenetic expression profiles, and stimulatory effects on growth hormone and gonadotropin gene expression

Despite its functional significance in mammals and birds, the biological role of gonadotropin-inhibitory hormone (GnIH) in reproduction is still far from being fully understood in teleosts. In the current study, we have identified LPXRFa, the piscine ortholog of GnIH, and its cognate receptor (LPXRFa-R) in yellowtail kingfish (YTK), which is considered as a promising species for aquaculture industry worldwide. The YTK cDNA sequence of lpxrfa was 534 base pair (bp) in length and encoded a 178-amino acids (aa) preprohormone. The LPXRFa precursor comprised three putative peptide sequences that included –MPMRF, –MPQRF, or -LPERL motifs at the C-termini, respectively. The YTK lpxrfa-r cDNA sequence was composed of 1265 bp that gave rise to a LPXRFa-R of 420 aa, encompassing the characteristic seven hydrophobic transmembrane domains. In males, both lpxrfa and lpxrfa-r transcripts could be detected at high levels in the brain and testis. In females, a noteworthy expression of lpxrfa was observed in the brain and ovary, while the expression of lpxrfa-r was especially evident only in the brain. To study the ontogeny of LPXRFa system, transcript levels were also investigated during early life stages. Variable expression of the LPXRFa system was observed during all stages of YTK embryogenesis. The highest expression of lpxrfa and lpxrfa-r were noticed at 7 dph and 15 dph, respectively. Furthermore, LPXRFa peptides stimulated growth hormone (gh), luteinizing hormone (lhβ) and follicle-stimulating hormone (fshβ) gene expression from the pituitary. Taken together, our results provide initial evidence for the existence of the LPXRFa system in yellowtail kingfish and suggest its possible involvement at early development and reproductive functions.

Growth, osmoregulatory and hypothalamic–pituitary–somatotropic (HPS) axis response of the juvenile largemouth bass (Micropterus salmoides), reared under different salinities

A 40 day experiment was conducted to investigate the effects of different salinities (0, 5 and 10 ppt) on the growth, osmoregulatory and hypothalamic–pituitary–somatotropic (HPS) axis response of juvenile largemouth bass (Micropterus salmoides). At the same time, two extra groups salinities (8 and 9 ppt) were used to explore the threshold of osmoregulation in M. salmoides to salinity stress. The survival were 94.45 %, 98.15 % and 32.00 % in 0, 5, 10 ppt, respectively. According the final body weight, specific growth rate (SGR), feed conversion ratio (FCR), condition factor (K) and chemical composition of muscle, largemouth bass should not be cultured at or above 10 ppt and 5 ppt is better than 0 ppt. The results found that the content of serum prolactin (PRL) and cortisol (COR) were no significant differences between groups of the 0, 5, 8, 9 and 10 ppt. Compared with the control group (0 ppt), the serum thyroxine (T4) content of 8 and 9 ppt groups decreased significantly and the serum triiodothyronine (T3) content all decreased significantly. Serum osmolality increased with increasing salinity. Na+-K+-ATP (NKA) and Ca2+-Mg2+-ATP (CMA) activities in the gills of largemouth bass at 0, 5, 8, 9 and 10 ppt showed tendency of ascend at first and descend at last, among which the activities in 10 ppt were significantly lowest. Gene expression of hepatic growth hormone (GH) at 10 ppt was highest. Meanwhile, insulin-like growth factor-I (IGF-I) expression at salinities of 8, 9 and 10 ppt were significantly higher than those at 0 and 5 ppt. Taken together, the findings of this study provide guidance for the practical rearing of largemouth bass in saline waters and contribute to research on stress physiology.

Cloning and expression of the growth hormone gene and its effect on the proliferation of skeletal muscle cells of Guizhou cattle

The aim of this study was to investigate the expression of growth hormone (GH) gene on skeletal muscle cell proliferation of Guizhou cattle. The coding sequence of cattle GH gene was amplified by reverse transcription PCR, cloned into the pUCM-T vector and then used to construct the GH gene overexpression vector pEGFP-N3-GH. The expression of the GH gene in skeletal muscle-related tissues (psoas major and longissimus dorsi) of Guizhou cattle was determined by real-time fluorescent quantitative PCR (RT-qPCR). This was followed by culturing and identification of the bovine primary skeletal muscle cells. Subsequently, we introduced the GH gene overexpression vector into the cells to investigate its effect on the proliferation of bovine skeletal muscle cells and the expression of insulin like growth factor 1 and 2 genes related to skeletal muscle growth and development. RT-qPCR results showed that the expression level of GH gene was higher in the psoas major than in the longissimus dorsi of Guizhou cattle, and the expression level in the psoas major of Guanling cattle and Weining cattle was significantly higher than in the longissimus dorsi (P<0.05). The transfection and proliferation results showed that pEGFP-N3-GH significantly increased the expression of GH, IGF-1, and IGF-2 genes in skeletal muscle cells compared to pEGFP-N3 (PP<0.05), and that overexpression of the GH gene also significantly increased the proliferation rate of skeletal muscle cells at the four periods examined (PP<0.01). Our results suggest that GH gene can promote the proliferation of skeletal muscle cells of Guizhou cattle and exerts a positive regulatory effect. This lays the foundation for further exploring the mechanism by which the GH gene affects the growth and development of Guizhou cattle.