Effect of particle size of insoluble fibre on growth performance, apparent ileal digestibility and caecal microbial population in broiler chickens fed barley-containing diets.

1. This study was conducted to investigate the effect of particle size of insoluble fibre on growth performance, apparent ileal digestibility (AID) and caecal microbial population in broiler chickens fed barley-containing diets. 2. The dietary treatments included: a barley-based diet (control, CTL) or test diets which contained high-fibre ingredients, either sunflower hulls (SFH), sugarcane bagasse (SB) or wheat bran (WB) ground through a 1.0 (fine) or 3.0 mm (coarse) screen that were added to the control diet at 30 g/kg. 3. For the entire experimental period, insoluble fibre inclusion improved ADG (P < 0.05) and FCR (P < 0.05) compared to the CTL group. Broilers fed SFH had higher (P < 0.05) ADG and better (P < 0.05) FCR than broilers fed SB. 4. Fibre inclusion increased the relative weight of breast and thigh and decreased relative weight of liver compared to the CTL group, but coarse grinding of the SB decreased relative weight of abdominal fat (P < 0.05). 5. The digestibility of nutrients increased with dietary inclusion of insoluble fibre compared to the CTL group. Coarse grinding of SFH increased AID of crude protein compared to the coarse grinding of WB or SB. Fine grinding of various types of fibre improved the AID of fat (as ether extract) and organic matter (P < 0.05). 6. Fine grinding of the WB decreased caecal populations of E. coli. The inclusion of SFH increased caecal populations of Lactobacillus spp. (P < 0.05). Coarse grinding of various types of fibre decreased the caecal population of coliforms (P < 0.05). 7. The inclusion of WB increased digesta viscosity in the ileum compared to samples from the SB and SFH groups (P < 0.05). Coarse grinding of various types of fibre decreased the digesta viscosity in the ileum (P < 0.05). 8. Overall, the data showed that dietary inclusion of insoluble fibre improved growth performance, increased AID of nutrients and decreased ileal viscosity in the birds fed diets containing barley.

Sequence and expression analysis of cardiac ryanodine receptor 2 in broilers that died from sudden death syndrome.

Sudden death syndrome (SDS) is a stress-related disease in broilers with no diagnostic clinical or necropsy findings. SDS is associated with ventricular tachycardia (VT) and ventricular fibrillation (VF); however, its pathogenesis is not precisely described at the molecular level. Dysfunction of ryanodine receptor 2 (RYR2), that controls rapid release of Ca2+ from the sarcoplasmic reticulum (SR) into the cytosol during muscle contraction, has been associated with VT and sudden cardiac death (SCD) in human patients with structurally normal heart, but there is no report describing abnormalities in RYR2 in diseased broilers. In order to advance our knowledge on the molecular mechanisms predisposing broilers to fatal arrhythmia, the present study was conducted to determine the occurrence of possible mutations and changes in the expression level of the chicken RYR2 gene (chRYR2) in broilers that died from SDS. An increase in mRNA expression level and nine novel point mutations in chRYR2 were found in relation to SDS. In conclusion, susceptibility to lethal cardiac arrhythmia in SDS may be associated with specific changes in intracellular Ca2+ cycling components such as RYR2 due to mutation and dysregulation. Finding the probable association of SDS with gene defects can be applied to select for chickens with lower susceptibility to SDS and decrease the poultry industry losses due to SDS mortality. RESEARCH HIGHLIGHTS Investigation of the occurrence of possible mutations and changes in the expression level of chicken RYR2 gene (chRYR2) in broilers that died from SDS. Increase in the mRNA expression level of chRYR2 in relation to SDS. Nine novel point mutations in chRYR2 of broilers that died from SDS. Possible connection between susceptibility to lethal cardiac arrhythmia in SDS and changes in intracellular Ca2+ cycling machinery, such as RYR2, due to mutation and dysregulation.

Polymorphism identification and cardiac gene expression analysis of the calsequestrin 2 gene in broiler chickens with sudden death syndrome.

Sudden death syndrome (SDS) in broilers is a cardiac disease associated with ventricular tachycardia (VT) and ventricular fibrillation (VF); however, its pathogenesis at the molecular level is not precisely determined. Downregulation and mutations of calsequestrin 2 (CASQ2), a major intracellular Ca(2+) buffer, have been associated with VT and sudden cardiac death (SCD) in humans but in chickens there is no report describing CASQ2 abnormalities in cardiac diseases. In order to better understand the molecular mechanisms predisposing the myocardium to fatal arrhythmia in broilers, the mRNA expression level of chicken CASQ2 gene (chCASQ2) in the left ventricle of dead broilers with SDS was determined and compared to healthy broilers using quantitative real-time PCR (qPCR). To determine the probable mutations in chCASQ2, PCR and direct sequencing were also done. Results showed a reduction in chCASQ2 expression in broilers dead by SDS. Three novel mutations (K289R, P308S, D310H) which are absent in healthy broilers were observed in chCASQ2. It is concluded that susceptibility to fatal cardiac arrhythmia in SDS may be associated with changes in intracellular Ca(2+) balance due to mutation and downregulation of chCASQ2.

Polymorphism of P53-Ets/AP1 transactivation region of MDM2 oncogene and its immunohistochemical analysis in canine tumours.

Mouse Double Minute-2 (MDM2) is an ubiquitin ligase which is overexpressed or its promoter polymorphism has been reported in different tumours. The objective of this study was to examine the MDM2 protein expression and its promoter polymorphism in some canine tumours. Twenty specimens were collected from 20 dogs with 15 mammary gland carcinomas, 3 lymphomas, 1 transmissible venereal tumour and 1 trichoblastoma. Samples were analysed immunohistochemically using human antibody against MDM2 protein. PCR and DNA sequencing were carried out to identify MDM2 promoter polymorphism. MDM2 gene was expressed in 13 of 20 samples including 11 mammary carcinomas, 1 lymphoma and 1 trichoblastoma. We found 94% homology between canine and human sequences. Four mutations including G169C, A177G, G291T and A177G were identified in different types of breast carcinomas. An extra p53 response element was found in a mixed mammary carcinoma.

Cytoprotective and anti-apoptotic effects of Satureja khuzestanica essential oil against busulfan-mediated sperm damage and seminiferous tubules destruction in adult male mice.

We studied the protective effect of Satureja khuzestanica essential oil (SKEO) against damage caused by busulfan on testis in male mice. The NMRI mice (n = 40) were assigned to four groups including: G1: control, G2: treated with busulfan for 4 days (3.2 mg kg(-1)), G3: receive busulfan (4 days, 3.2 mg kg(-1)) and SKEO (28 days, 225 mg kg(-1)) at the same time, G4: pre-treated with SKEO (7 days, 225 mg kg(-1)) and subsequently cotreated with busulfan (4 days, 3.2 mg kg(-1)) and SKEO (28 days, 225 mg kg(-1)). The histological changes of testis were analysed using H&E staining. Sperm parameters, cytotoxic and apoptotic factors were also studied by computer-aided sperm analyzer, MTT and TUNEL assays respectively. Our results showed that SKEO pre-administration significantly improved all parameters of epididymal spermatozoa and decreased germinal epithelium destruction following busulfan chemotherapy. We also found lower MTT levels and TUNEL-positive cells in SKEO pre-treated groups. In conclusion, SKEO possesses beneficial effects on sperm parameters when taken before chemotherapy and continued during and after chemotherapy for a long time, than when used short-term coinciding with the chemotherapy. Our results support valuable data about the application of SKEO for protection against adverse effects of busulfan on male genital system in patients under chemotherapy.

Modulation of cutaneous wound healing by silymarin in rats.

OBJECTIVE: To investigate the effect of topical application of silymarin on full-thickness cutaneous wounds in rats. METHOD: A full-thickness cutaneous defect (2×2cm) was induced on the back of 85 male and female Wister rats. The animals were randomly divided into four groups (n=20 in each group), treated with 1ml basal cream (placebo group), low-dose (6mg/ml/rat) and high-dose (12mg/ml/rat) silymarin, and untreated (control). Five rats remained uninjured to serve as comparisons for biomechanical analysis. Wounds were evaluated 10, 20 and 30 days after injury, through histopathologic, biochemical and biomechanical analyses. RESULTS: There was a significant (p < 0.05) increase observed in the amount of glycosaminoglycans and collagen present on days 10, 20 and 30 for both low-dose and high-dose silymarin groups. Low-dose silymarin reduced the number of lymphocytes and enhanced the number of fibrocytes at the earlier stages of wound healing; however, high-dose silymarin reduced both lymphocytes and macrophages, and increased number of fibrocytes at the later stages of wound healing. Silymarin significantly improved alignment of the healing tissue, enhanced maturity of the collagen fibres and fibroblasts (p < 0,05), and increased the ultimate tensile strength and stress of the healing tissue. CONCLUSION: The results suggest that topical application of silymarin improved the morphological, biochemical and biomechanical properties of experimentally-induced wound defects in rats. DECLARATION OF INTEREST: There were no external sources of funding for this study. The authors have no conflicts of interest to declare.

Gene expression pattern of adiponectin and adiponectin receptors in dominant and atretic follicles and oocytes screened based on brilliant cresyl blue staining.

Adiponectin and its receptors (AdipoR1 and AdipoR2) are novel endocrine systems that act at various levels to control male and female fertility. The aim of this study was to determine whether adiponectin and its receptors gene expression levels differ between dominant follicle (DF) and atretic follicle (AF) and also between oocytes which were stained positively and negatively with brilliant cresyl blue (BCB(+) and BCB(-)). Based on estradiol/progesterone ratio, follicles from ovaries were classified as AFs and DFs. The stages of estrous cycle (follicular or luteal phases) were defined by macroscopic observation of the ovaries and the uterus. Oocytes were stained with BCB for 90 min. The relative expression of adiponectin, AdipoR1 and AdipoR2 mRNA in theca and cumulus cells and oocytes of different follicles were determined by quantitative real time PCR. Adiponectin and its receptors genes were clearly expressed higher (P<0.05) in theca and cumulus cells and oocytes of DFs than those of AFs during the follicular and luteal phases. BCB(+) oocytes showed a higher (P<0.05) expression of adiponectin and its receptors compared with their BCB(-) counterparts. Positive correlation (r>0.725, P<0.001) was observed between adiponectin mRNA level in ovarian cells of DFs and follicular fluid E2 concentration in follicular phase. Adiponectin mRNA abundance in ovarian cells of AFs showed a significant negative correlation with follicular fluid progesterone concentration in follicular and luteal phases (r<-0.731, P<0.001). This work has revealed the novel association of adiponectin and its receptors genes with follicular dominance and oocyte competence, thereby opening several new avenues of research into the mechanisms of dominance and competence in animal and human.

Changes in the gene expression of adiponectin and adiponectin receptors (AdipoR1 and AdipoR2) in ovarian follicular cells of dairy cow at different stages of development.

Adiponectin is one of the most important, recently discovered adipocytokines that acts at various levels to control male and female fertility through central effects on the hypothalamus-pituitary axis or through peripheral effects on the ovary, uterus, and embryo. We studied simultaneous changes in the gene expression pattern of adiponectin and adiponectin receptors 1 and 2 (AdipoR1 and AdipoR2) in granulosa and theca cells, cumulus-oocyte complex, and in corpus luteum in healthy bovine (Bos tarus) follicles at different stages of development. The expression levels of adiponectin, AdipoR1, and AdipoR2 mRNA were lower (P<0.05) in granulosa and cumulus cells in comparison with that in theca cells and oocyte. In contrast with the oocyte, AdipoR1 in granulosa, theca, and luteal cells was expressed (P<0.05) more than AdipoR2. Adiponectin expression increased (P<0.05) in granulosa cells and in cumulus-oocyte complex during follicular development from small to large follicles. Opposite results were observed in theca cells. Expression of adiponectin was highest in the late stages of corpus luteum (CL) regression, whereas lower expression was recorded in active CL (P<0.05). AdipoR1 and AdipoR2 expression increased during the terminal follicular growth in granulosa and theca cells (P<0.05) and during the luteal phase progress in CL. There was positive correlation between adiponectin mRNA level in granulosa cells from large follicles and follicular fluid estradiol concentration (r=0.48, P<0.05) and negative correlation between adiponectin mRNA abundance in theca cells and follicular fluid progesterone concentration (r=-0.44, P<0.05). In conclusion, we found that the physiologic status of the ovary has significant effects on the natural expression patterns of adiponectin and its receptors in follicular and luteal cells of bovine ovary.