Damage of polyethylene microplastics on the intestine multilayer barrier, blood cell immune function and the repair effect of Leuconostoc mesenteroides DH in the large-scale loach (Paramisgurnus dabryanus).

Polyethylene microplastics (PE-MPs) has become a global concern due to their widespread distribution and hazardous properties in aquatic habitats. In this study, the accumulation effect of PE-MPs in the intestine of large-scale loach (Paramisgurnus dabryanus) was explored by adding different concentrations of PE-MPs to the water, the destination of PE-MPs after breaking the intestinal barrier and the effects caused. The collected data showed that PE-MPs accumulation for 21d altered the histomorphology and antioxidant enzyme activity of the intestine, induced dysbiosis of the intestinal flora. 10 mg/L of PE-MPs induced a significant increase in the transcript levels of intestinal immunity factors in loach after 21d of exposure. Moreover, the levels of diamine oxidase (DAO) and d-lactic acid (D-Lac) in the gut and serum of loach were significantly increased after exposure to PE-MPs at all concentrations (1, 5, 10 mg/L). Subsequently, the presence of PE-MPs was detected in the blood, suggesting that the disruption of the intestinal multilayer barrier allowed PE-MPs to spill into the circulation. The accumulation of PE-MPs (1,5,10 mg/L) in the blood led to massive apoptosis and necrosis of blood cells and activated phagocytosis in response to PE-MPs invasion. To alleviate the damage, this study further exposure the effect of probiotics on PE-MPs treated loach by adding Leuconostoc mesenteroides DH (109 CFU/g) to the feed. The results showed that DH significantly increased the intestinal index and reduced the levels of DAO and D-Lac. To investigate the reason, we followed the PE-MPs in the intestine and blood of the loach and found that the number of PE-MPs particles was significantly reduced in the probiotic group, while the PE-MPs content in the feces was elevated. Thus, we concluded that DH reducing the accumulation of PE-MPs in the intestinal by increases fecal PE-MPs, which in turn mitigates the damage to the intestinal barrier caused by PE-MPs, and reduces the amount of PE-MPs in the blood. This work offers a robust analysis to understand the mechanisms of damage to the intestinal barrier by MPs and the fate of MPs after escaping the intestinal barrier and provide a new perspective on the application of probiotics in mitigating PE-MPs toxicity.

PvMR1, a novel C-type lectin plays a crucial role in the antibacterial immune response of Pacific white shrimp, Penaeus vannamei.

C-type lectins (CTLs) are important immune molecules in innate immune, which participate in non-self recognition and clearance of pathogens. Here, a new CTL with two distinct C-type lectin domains (CTLDs) from Pacific white shrimp Penaeus vannamei, designated as PvMR1 was identified. The obtained PvMR1 coding sequence (CDS) was 1044 bp long encoding a protein with 347 amino acids. PvMR1 had two CTLD, a conserved mannose-specific EPN motif and a galactose-specific QPD motif, clustering into the same branch as the crustacean CTLs. PvMR1 was widely distributed in shrimp tissues with the highest transcription level in the hepatopancreas, with significantly induced mRNA expression on the hepatopancreas and intestines after immune challenge with Vibrio anguillarum. In vitro assays with recombinant PvMR1 (rPvMR1) protein revealed that it exhibited a wide range of antimicrobial activity, bacterial binding ability, and bacterial agglutination activity in a Ca2+-independent manner. Moreover, PvMR1 promoted bacterial phagocytosis in hemocytes. Furthermore, rPvMR1 treatment could significantly enhance the bacterial clearance in hemolymph and greatly improved the survival of shrimp under V. anguillarum infection in vivo. These results collectively suggest that PvMR1 plays an important role in antibacterial immune response of P. vannamei.

Identification and characterization of the adipogenesis in intramuscular and subcutaneous adipocytes of the goose (Anser cygnoides).

Chinese geese are domesticated from wild swan (Anser cygnoides), which have maintained a strong capacity of fat deposit. Fat mainly distributes subcutaneous, abdominal, intermuscular or intramuscular in poultry, and they display some special physiological and biochemical characteristics in different parts. This study aimed to characterize the adipogenesis in intramuscular (IM) and subcutaneous (SC) adipocytes of the goose. Here, IM and SC preadipocytes were isolated from the 26-day-old Yangzhou goose embryos, and subsequently induced them to differentiate into mature adipocytes. The results showed that SC preadipocytes grew a little faster than IM preadipocytes during the logarithmic multiplication phase (p < 0.05). Meanwhile, SC adipocytes accumulated more lipid than IM adipocytes during the differentiation process in vitro (p < 0.01). In addition, the expression level of key genes involved in adipogenesis, including peroxisome proliferator activated receptor γ/α (PPARγ/α), CCAAT/enhancer binding protein-α/ß (C/EBPα/ß), adipocyte fatty acid binding protein 4 (FABP4), and lipoprotein lipase (LPL) were detected. PPARγ, C/EBPα, FABP4, and LPL, were predominantly expressed in SC adipocytes, whereas C/EBPß was highly expressed in IM adipocytes. Taken together, these results demonstrated that SC preadipocytes tended to grow faster and accumulate more lipid than IM adipocytes, and show greater potential for adipogenesis.

The specificity protein 3 (SP3) gene in ducks (Anas platyrhynchos): cloning, characterization and expression during viral infection.

Specificity Protein 3 (SP3) is a newly identified regulator of tumor growth and invasiveness in humans. In this study, we identified and characterized the function of duck SP3 (duSP3). The full-length cDNA sequence of the duSP3 gene was cloned via rapid amplification of cDNA ends. It contained 2468 nucleotides, including a 111 base pair (bp) 5'-untranslated region (UTR), 215 bp 3'-UTR, and 2142 bp open reading frame (ORF), which encoded a 713 amino acid (AA) strongly conserved with Avian SP3. Tissue specificity analysis demonstrated that duSP3 was constitutively expressed in the eight tissues tested: liver, spleen, lung, heart, kidney, thymus, breast, and leg; and low expression levels were observed in all tissues, except the spleen and thymus. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed that duSP3 expression rapidly increased in vitro after stimulation with both the hepatitis virus (DHV-1) and polyriboinosinic polyribocytidylic acid (poly(I:C)). However, the expression under these treatments varied in kidney and liver tissues; in the liver, duSP3 increased significantly at 36 h after the DHV-1 treatment and peaked at 72 h after poly(I:C) stimulation. These results suggested that SP3 may play a positive role in immune responses against viral infections in ducks.

Cytotoxicity, genotoxicity, oxidative stress, and apoptosis in HepG2 cells induced by the imidazole ionic liquid 1-dodecyl-3-methylimidazolium chloride.

This study purposes to assess the cytotoxicity of 1-dodecyl-3-methylimidazolium chloride ([C12 min]Cl) in human hepatocellular carcinoma (HepG2) cells. To this end, HepG2 cells were exposed to a range concentration of [C12 min]Cl and evaluated cell viability, genotoxicity, oxidative stress, apoptosis, cell cycle, and apoptosis-related gene expression to determine cytotoxicity. The outcomes showed that [C12 min]Cl curbed HepG2 cell growth and reduced cell viability in a concentration- and time-dependent manner. Moreover, our assay results also revealed that exposure to [C12 min]Cl prompted DNA damage and apoptosis, reduced SOD and GSH content, enhanced MDA level, and changed the cell cycle of HepG2 cells. In addition, [C12 min] Cl caused alters in the expression levels of p53, Bax, and Bcl-2, indicating that p53 and Bcl-2 family may be involved in the cytotoxicity and apoptosis of HepG2 cells induced by [C12 min]C1. In summary, these results indicate that [C12 min]Cl exerts genotoxicity, physiological toxicity and prompts apoptosis in HepG2 cells, and is not an alleged green solvent.

Molecular cloning, characterization of dax1 gene and its response to progesterone in Misgurnus anguillicaudatus.

Progesterone (P4) are aquatic contaminants that can impair fish reproduction even in low concentrations. The aim of this study was to investigate the effects of P4 on the sex differentiation, by quantitative determination of transcriptional changes of a candidate target gene (dax1, has a function in the sex determination and gonadal differentiation of several vertebrate species) in Misgurnus anguillicaudatus. We first cloned and characterized the full-length cDNAs for the dax1 in M. anguillicaudatus (designated as Ma-dax1). Sequence analysis reveals that Ma-dax1 shares high homology with dax1 in other species. Quantitative real-time PCR (qRT-PCR) and in situ hybridization showed that Ma-dax1 gene was highly conserved during vertebrate evolution and involved in a wide range of developmental processes including embryogenesis, central nervous system development and gonad development. For the P4 administration assay, groups of mature fish were exposed for 1, 7, 14, 21 and 28 days to nominal concentrations of 10, 100, and 1000 ng/L P4 in a flow-through system. Quantification of Ma-dax1 transcripts revealed the expression of Ma-dax1 mRNA is altered after P4 treatment in mature gonads. Those showed that P4 could influence the sexual development and sex differentiation in M. anguillicaudatus by disturbing sex differentiation-associated gene expression, and dax1 can be used as a sensitive molecular biomarker for early warning to monitor the environmental progestins chemicals in fresh water environment.

Molecular cloning, characterization, and expression profiles of the Sox3 gene in Chinese loach Paramisgurnus dabryanus.

A number of studies have established that in vertebrates, Sox3 is involved in a wide range of developmental processes, including sex differentiation and neurogenesis. However, the exact functions of the Sox3 gene have not been documented so far in teleosts. Here, we cloned the full length cDNA of Sox3 from the teleost fish, Paramisgurnus dabryanus, which we designated PdSox3. Sequence analysis revealed that PdSox3 encodes a hydrophilic protein, and shares high homology with Sox3 in other species, ranging from mammals to fishes. Quantitative real-time reverse transcription PCR, and in situ hybridization showed that PdSox3 is consistently expressed during embryogenesis, mainly localized in the developing central nervous system. Tissue distribution analyses revealed that PdSox3 is abundant in the adult brain, especially in particle cell layer. Furthermore, PdSox3 expression was higher in gonads, in primary spermatocyte cells, primary oocytes, and previtellogenic oocyte cells. All of these results suggest that PdSox3 plays an important role in early embryonic development, in particular the formation and development of the nervous system, and gonad development, similarly to other vertebrates. This is the first report describing Sox3 gene expression from this species, and the results are necessary to provide fundamental information on both the functional and evolutionary role of Sox3 across different species.

Cloning, characterization and function analysis of DAX1 in Chinese loach (Paramisgurnus dabryanus).

The mechanisms of sex determination and differentiation have not been elucidated in most fish species. In this study, the full-length cDNAs of DAX1 was cloned and characterized in aquaculture fish Chinese loach (Paramisgurnus dabryanus), designated as Pd-DAX1. The cDNA sequence of Pd-DAX1 was 1261 bp, including 795 bp open reading frame (ORF) encoding 264 amino acids. Pd-DAX1 shares highly identical sequence with DAX1 homologues from different species. The expression profiles of Pd-DAX1 in different developmental stages and diverse adult tissues were analyzed by quantitative real-time RT-PCR and in situ hybridization (ISH). Pd-DAX1 was continuously expressed during embryogenesis, with the extensive distribution in the development of the central nervous system. Tissue distribution analysis revealed that Pd-DAX1 expressed widely in adult tissues, with the highest expression level found in testis, moderate level in ovary, showing a sex-dimorphic expression pattern. Pd-DAX1 mainly located in spermatogonia cells, spermatocytes, primary oocytes and previtellogenic oocyte cells, implying that Pd-DAX1 may involve in gametogenesis. These preliminary findings suggest that Pd-DAX1 gene is highly conserved during vertebrate evolution and involved in a wide range of developmental processes including embryogenesis, central nervous system development and gonad development.

Toxicity of imidazoles ionic liquid [C16mim]Cl to Hela cells.

Our study aimed to evaluate the toxicity of 1-hexadecyl-3-methylimidazolium chloride ([C16min]Cl) on the human cervical carcinoma (Hela) cells. We evaluated toxicity, cell viability, genotoxicity, oxidative stress, apoptosis, and apoptosis-related gene expression in Hela cells following exposure to [C16min]Cl. The results indicated that [C16min]Cl inhibited the growth of Hela cells, decreased cell viability, induced DNA damage and apoptosis, inhibited superoxide dismutase, decreased glutathione content, as well as increased the cellular malondialdehyde level of Hela cells. Moreover, [C16min]Cl induced changes in the transcription of p53, Bax and Bcl-2, suggesting that the p53 and Bcl-2 family might have been involved in the cytotoxicity and apoptosis induced by [C16min]Cl in Hela cells. Taken together, these results revealed that [C16min]Cl imparts oxidative stress, genotoxicity, and induces apoptosis in Hela cells; hence, it is not a green solvent.

Comparison of muscle fiber characteristics and glycolytic potential between slow- and fast-growing broilers.

Muscle fiber characteristics had beneficial effects on meat masses and meat quality in broilers. Its number is determined at birth and directly affects the growth and development of muscle fibers after birth. However, whether the muscle fiber characteristics in different types of chickens are different at birth has not been fully documented. In this study, the 1-day-old Xueshan chicken (slow-growing broiler) and Ross 308 broiler (fast-growing broiler) were selected, respectively, and the fiber type distribution, fiber density, and fiber size in the breast (pectoralis major, PM) and leg (gastrocnemius, GAS) muscles were detected. The results showed that the PM only made up of type IIB fibers regardless of breed, and that few type I fibers (approximately 17.55%) was identified in GAS of Ross 308 broiler. The PM muscles had significantly higher fiber density, lower cross-sectional area and diameter than those of GAS muscles in both 2 breeds (P < 0.05). The highest fiber density was observed in PM of Xueshan chicken. Furthermore, the muscle fiber characteristics were partly controlled by glycolytic potential (GP), and the GP was also invesgated. The GP in PM and GAS of Ross 308 broiler were higher than in Xueshan chicken (P < 0.05). Taken together, 1-day-old Xueshan chicken exhibited higher fiber density and lower GP compared to 1-day-old Ross 308 broiler, especially in PM, which could not only reveal the differences of muscle characteristics among different types of chickens, but also explore a new way to improve the masses and quality of poultry meat.

Comparative phosphoproteomic provides insights into meat quality differences between slow- and fast-growing broilers.

The selection of broilers for augmented growth rate and breast yield has been accompanied by deterioration in meat quality. To characterise the meat quality differences between slow- (SG) and fast-growing broilers (FG), Xueshan and Ross 308 chickens were employed to determine the mechanisms causing these differences. SG meat was found to display more redness and yellowness, higher shear force, pH24h, and protein content, with lower intramuscular fat (IMF) content than FG meat. Further, based on comparative phosphoproteomic analysis (SG/FG), upregulated phosphorylated myofibrillar proteins resulted in larger fibres, which contributed to lower pressing loss and tenderness. The phosphoproteins of glycolytic enzymes, phosphorylase kinases, and calcium-related proteins were significantly downregulated, which reduced the acidity of the meat. SLC7A5 at Ser21, MRC2 at Ser1359 and CRAT at Ser341, AUP1 at Ser377 positively affected protein and IMF deposition, respectively. Together, these phosphoproteins elicit vital information for the genetic improvement of chicken meat quality.

Fiber characteristics and meat quality of different muscular tissues from slow- and fast-growing broilers.

Chicken meat is an important source of high-quality animal protein. Its consumption continues to grow in both developed and developing countries. Muscle fiber characteristics are key determinants of meat quality and quantity. Skeletal muscle is a highly plastic tissue that is affected by breed differences and muscular tissues. However, studies regarding the effects of different breeds and muscular tissues on the fibers and meat quality traits in broilers are lacking. In this study, Ross 308 chickens (fast-growing [FG] broilers) and Xueshan chickens (slow-growing [SG] broilers) were selected, and their fiber and meat quality traits were characterized. The results showed that the breast muscle primarily comprised glycolytic fibers, whereas the leg muscle comprised glycolytic and a few oxidative fibers, regardless of the breed. The highest percentage of oxidative fibers (26.51%) appeared in the soleus muscle (SOL) of SG broilers. In addition, higher shear force, lower pressing loss, and thicker muscle fibers with less extracellular space were observed for SG meat than for FG meat. When comparing the different muscular tissues, a higher oxidative fiber percentage, ultimate pH, redness, and intramuscular fat (IMF) content were detected in the leg muscle than in the breast muscle in the 2 breeds. In summary, these data indicated that SG broilers had thicker muscle fibers than the FG broilers and that the leg muscle had more oxidative fibers than the breast muscle. Thicker fibers may contribute to increased firmness and more oxidative fibers lead to higher redness value and IMF content.

Effect of muscle fiber characteristics on meat quality in fast- and slow-growing ducks.

This study evaluated the effects of muscle fiber characteristics on meat quality traits in 45 female fast- and slow-growing ducks. Three duck breeds at typical market ages were selected and slaughtered, including fast-growing ducks (Cherry Valley duck) and slow-growing ducks (Small-sized Beijing duck and Liancheng White duck). M. pectoralis major (PM), m. soleus (SOL), m. gastrocnemius (GAS) and m. extensor digitorum longus (EDL) were used to assess muscle fiber characteristics as well as meat quality properties. The results showed that the fiber compositions in PM, GAS, and EDL muscles only consisted of fast-twitch fibers irrespective of the breeds, while a low percentage of slow-twitch fibers were observed in slow-growing ducks (17.03% and 29.14%). The significant clear differences of fiber diameter, fiber density and fiber cross-sectional area (CSA) was observed among three duck breeds. Small-sized Beijing ducks had the highest diameter and cross-sectional fiber area coupled with a dramatically lowest fiber density when compared to other 2 breeds both in breast and leg muscles. In addition, the meat quality traits such as moisture content, release water, and intramuscular fat content were significantly affected by the breeds. Slow-growing ducks, especially Liancheng White ducks, exhibited higher release water, intramuscular fat content, as well as lower moisture content (P < 0.05) compared to the fast-growing ducks. The lower pH24 h value and shear force tended to be present in breast of Liancheng White ducks (P < 0.05). The higher protein content and collagen content were detected in breast of Liancheng White ducks and the leg muscle of Small-sized Beijing ducks (P < 0.05), respectively. Finally, the correlation coefficients between muscle fiber characteristics and meat quality showed that the diameter, density and CSA of fibers had a moderate or significant correlation with pH, shear force value, moisture content, and protein content of meat in fast-growing ducks. In slow-growing ducks, muscle fiber characteristics had a moderate or significant correlation with pH, shear force value, release water, protein content, and intramuscular fat content of meat. These results indicated that muscle fiber characteristics is a useful parameter to explain in parts the variation of meat quality including pH, shear force value, and protein content of meat, both in slow-growing ducks and fast-growing ducks.

Difference in developmental dynamics between subcutaneous and abdominal adipose tissues in goose (Anser Cygnoides).

Goose (Anas cygnoides), as a typical species domesticated from a migratory bird, has maintained the capability of depositing excess lipid and preferentially accumulating fat within the abdomen and subcutaneous, which not only leads to decrease in yield of meat product, but also affects the feed conversion rate. Here, an experiment was conducted to examine the difference in developmental dynamics between subcutaneous (SAT) and abdominal adipose tissues (AAT) in goose. The results showed that SAT could be clearly observed at embryonic days (E) 15, whereas AAT were clearer until E20. Although the weights of SAT and AAT showed a significant rising with advancing age (P < 0.05), their gains were not completely uniform, and more adipose deposited preferentially toward AAT after birth (P < 0.05). Additionally, a clear expansion in adipocyte size was observed in AAT and SAT during embryonic stages (P < 0.05). The average adipocyte area in AAT continued to increase after birth (P < 0.05), while the cell areas in SAT were relatively invariable (P > 0.05). Furthermore, the expression levels of FABP4/aP2, ACSL1 and PPARγ were much higher in SAT than in AAT, whereas relative higher expression level of IL-6 was observed in the AAT during embryonic stages. After birth, the more expression of LPL and PPARα were detected in AAT than did in SAT (P < 0.05), whereas greater ATGL expression was in SAT (P < 0.05). Taken together, these findings suggest that AAT may display greater fat storage capacity than SAT accompanied by changes in cell area and lipogenic capacity. Considering that there is disparity in the individual adipose tissues, we suggested that careful consideration for the precise interventions used to control SAT or AAT deposition in meat-producing animals to improve feed efficiency.

Effect of marketable age on proximate composition and nutritional profile of breast meat from Cherry Valley broiler ducks.

Marketable age is an important determinant of meat quality. Cherry Valley duck (SM3 medium) is the most efficient Pekin-type duck and is the most widely farmed breed globally. However, whether marketable age determines the meat quality of Cherry Valley ducks is not well documented. The objective of this study was to investigate the effect of marketable age on the proximate composition and nutritional profile of breast meat from Cherry Valley broiler ducks. Ducks at 28, 38, 42, and 45 days old were selected and slaughtered, and their proximate composition, cholesterol and essential mineral compositions, and amino acids and fatty acid profile of breast meat lipid were determined. The results showed higher protein content and lower intramuscular fat content were observed in the 38-day-old ducks than in the 28-day-old birds (P < 0.05). Additionally, 38-day-old ducks contained higher Fe and Mg contents (P < 0.05), whereas 28-day-old birds had higher Zn and Ca contents (P < 0.05). The essential amino acid content in 38-day-old was about 95.29 g/kg, higher than that in 28-day-old birds (P < 0.05). The contents of C20:5 n-3, omega-6 polyunsaturated fatty acids, and polyunsaturated fatty acids were the highest in 38-day-old birds (P < 0.05), whereas the content of C20:4 n-6, DHA (C22:6 n-3), and saturated fatty acids in 28-day-old birds was the lowest (P < 0.05). Finally, a comprehensive evaluation model of multiple traits was developed by applying principal component analysis, and the meat nutrition of 38-day-old ducks was identified as the optimal. Taken together, the meat of 38-day-old ducks had an advantage in proximate composition, minerals content, essential amino acids, and fatty acids, and 38 d might be recommended as an appropriate marketable age to provide duck meat of high nutrition value.

Effects of integrated rice-duck farming system on duck carcass traits, meat quality, amino acid, and fatty acid composition.

Integrated rice-duck farming (RD) system, which aims to improve the welfare of ducks, has gained popularity in Asian countries. However, the effects of RD system on the carcass and quality traits of duck meat have not been evaluated. Here, a paddy field experiment was conducted to examine the effects of RD system on the carcass and quality traits of duck meat. A total of 180 Jinding ducklings (7 days old) were randomly divided into 2 rearing systems of floor pen rearing (FPR) system and RD system. After 11 weeks, 12 ducks from each rearing system (6 males and females each) were used for carcass traits, meat quality, amino acid, and fatty acid analyses. The results showed that ducks reared in the RD system had higher carcass yield and intramuscular fat content (P < 0.05) than those reared in the FPR system; however, ducks reared in the RD system had lower protein and moisture content (P < 0.05). Additionally, the concentration of essential amino acids, including Tyr, Val, Met, Phe, His, Ala, Arg, and Pro, was higher in the breast muscle of ducks reared in the RD system than those reared in the FPR system. Furthermore, higher saturated fatty acid (C12:0, C14:0, C16:0, C18:0, and C21:0), monounsaturated fatty acid (C16:1, C18:1, and C18:1T), and polyunsaturated fatty acid (C22:2, C18:2n-6, and C22:6n3) content was recorded in the breast muscle of ducks reared in the RD system than those reared in the FPR system (P < 0.05). Taken together, our results indicated that the RD system improved the carcass traits, intramuscular fat, essential amino acids, and polyunsaturated fatty acids profiles of the ducks. These findings suggest that the RD system is an effective strategy to improve the welfare and meat quality of ducks.

Quantitative phosphoproteomic analysis unveil the effect of marketable ages on meat quality in geese.

The quality of poultry goose meat is closely related to its marketable ages, with meat quality varying with increasing marketable age. Geese of two marketable ages (70-day and 120-day) were selected to understand the mechanisms behind this effect. Darker and redder meat; chewier and higher water-holding capacity (WHC) as well as greater protein and intramuscular fat (IMF) content were observed in the breast muscle (BM) of 120-day-old geese as compared to 70-day-old geese. Quantitative phosphoproteomics revealed up-regulated phosphorylated myofibrillar proteins and glycolytic enzymes in 120BM contributed to chewier meat with higher WHC. Redder meat might be attributed to phosphorylated mitochondrial proteins interacting with glycolytic enzymes in energy metabolism. Additionally, phosphorylation of PLIN1 and PERM1 might positively affect IMF deposition. Taken together, these data provided a phosphoproteomics perspective for the effect of marketable ages on meat quality and a theoretical strategy for improving meat quality in geese of younger marketable age.

Effects of marketable ages on meat quality through fiber characteristics in the goose.

Goose meat is increasingly popular among consumers because of its good quality. The fiber characteristics have been well demonstrated to be key contributing factors of meat quality, and the marketable ages are also closely related to meat quality. However, little is known about the effect of different marketable ages on the quality of goose meat through its fiber characteristics. Here, fiber characteristics of Yangzhou geese of different marketable ages (70, 90, and 120 d) and their effect on meat quality were investigated. The results showed that only fast-twitch fibers were present in breast muscle, irrespective of age, and that few slow-twitch fibers could be identified in leg muscle, especially in gastrocnemius and extensor digitorum longus. Fiber diameter in breast muscle increased rapidly from age 70 d to 90 d, from 19.88 to 26.27 µm, and remained stable for 90 d thereafter. The diameter and cross-sectional area of muscle fiber continue to grow with day increasing in leg muscle. In addition, we measured the proximate composition and physical properties at different ages. Among the 3 marketable ages investigated, the 120-day-old geese had higher intramuscular fat and protein content, as well as lower moisture content, both in breast and leg meat. Greater lightness and pressing loss, with lower redness and shear force, were observed in the breast and leg meat of 70-day-old geese when compared with 90- or 120-day-old geese. Taken together, although older marketable age hardly affected muscle fiber type in geese, it would contribute to larger muscle fiber area, higher intramuscular fat and protein content, as well as redder and chewier meat. As a result, the reasonable marketable age should be taken into account to improve quality in goose meat production, and the marketable age of 90 or 120 d was recommended and it could potentially improve meat quality in goose meat production.

Molecular cloning and mRNA expression pattern of Sox4 in Misgurnus anguillicaudatus.

Sox4, a member of the SoxC subfamily which of the Sox family, plays important roles in the development of the vertebrate gonad and nervous system. We have cloned a Sox4 homologue fromthe brain of Misgurnus anguillicaudatus using homologous cloning and rapid amplification of cDNA ends. We named the cloned gene as MaSox4. The full-length cDNA was 2122 bp, containing a 718 bp 5'-untranslated region and a 267 bp 3'-untranslated region. The open-reading frame of the cloned gene encoded 378 amino acids and contained a characteristic HMG-box DNA-binding domain with the specific motif (RPMNAFMVW). Phylogenetic analysis indicated that MaSox4 is highly homologous to Sox4 in different species. Protein sequence analysis showed that MaSox4 is a nonsecretory hydrophilic protein. Quantitative real-time reverse transcription polymerase chain reaction and in situ hybridization assay revealed that MaSox4 was ubiquitously expressed during embryogenesis and is present in various adult tissues, especially in the central nervous system. Our study suggests that MaSox4 is highly conserved among vertebrates' evolution and might be involved in developmental processes such as embryogenesis, neurogenesis and gonad development.

Toxic effects of cyhalofop-butyl on embryos of the Yellow River carp (Cyprinus carpio var.): alters embryos hatching, development failure, mortality of embryos, and apoptosis.

As a universal environmental contaminant, the herbicide cyhalofop-butyl is considered to have infested effects on the embryonic development of aquatic species. The present study focused on an assessment of the impacts of cyhalofop-butyl on Yellow River carp embryos. It was found that cyhalofop-butyl inhibited the hatching of the embryos, and the hatching rate decreased with higher concentrations of the herbicide. The mortality rate was increased on exposure to cyhalofop-butyl and was significantly higher in the 1.6 and 2 mg/L treatment groups over 48 h. All of the embryos of the 2 mg/L treatment group died within the 48 h post-hatching stage. And the transcription of several embryos related to apoptosis was also influenced by cyhalofop-butyl exposure. Further, cyhalofop-butyl exposure leads to a series of morphological changes (pericardial edema, tail deformation, and spine deformation) in embryos, which were consistent with significant modifications in the associated genes. These results provided a scientific basis for further studies into the effects of cyhalofop-butyl on aquatic organisms.