Environmental enrichment improves the growth rate, behavioral and physiological response of juveniles of Clarias gariepinus under laboratory conditions.

Environmental enrichment (EE) improves the growth rate and welfare of some cultured fishes. However, most cultured fish species are raised in non-enriched housing conditions. Clarias gariepinus is an important commercial fish species, but little is known about the effect of EE on their welfare. This study examined the effect of different EE on the survival rate (SR), growth [mean weight gain (MWG), specific growth rate (SGR) and feed conversion ratio (FCR)], behavioral (feed response, aggressive acts and shoaling time) and physiological responses (blood glucose) of C. gariepinus. One hundred and twenty juveniles of C. gariepinus (31.65 ± 0.69 g) were randomly allocated at 10 fish/tank and subjected to either Plant Enriched (PE), Substratum Enriched (SE), Plant and Substratum Enriched (PSE) and Non-Enriched (NE) tanks in triplicates for 56-days. Behavioral acts were observed for 10 min twice daily, and glucose level in blood samples was evaluated. Data were checked for normality using the Shapiro-Wilk test before being analyzed with the Kruskal-Wallis test. SR and MWG were significantly higher in Clarias gariepinus exposed to SE, with no significant differences among PE, PSE and NE treatments. There was no significant difference between the SGR of PSE and NE. FCR was similar between treatments. The highest condition factor (k) was recorded in SE tanks. Duration of feed response was shorter in SE, but there was no significant difference between the feed response of C. gariepinus exposed to PE and PSE. C. gariepinus exposed to PE, SE and PSE displayed a similar frequency of aggressive acts. African catfish reared in NE (barren) tanks had the least duration of shoaling period. The experiment consistently found the highest and least glucose values in PSE and SE. In conclusion, environmentally enriched housing tanks with SE resulted in the best MWG with a reduced level of aggression in C. gariepinus under laboratory conditions. Thus, EE might be applicable to boost fish productivity on a commercial scale.

Influence of exogenous corticosterone on testicular function and mating behavior of Nigerian indigenous cocks.

In bridging the knowledge gap on stress physiology of Nigerian indigenous chickens, this study investigated the effect of exogenous corticosterone (eCORT) as stress inducing agent on the testicular function and mating behavior of Nigerian indigenous cocks. Twenty-four (24) cocks and one hundred and forty four (144) hens (mating ratio of 1 cock: 6 hens) were grouped into four and assigned to each of the four eCORT treatments (0, 2, 4 and 6 mgeCORT/KgBW) daily for 14 days. Semen samples were collected on days 0, 7 and 14 and analyzed for semen volume (SV), progressive sperm motility (PSM), membrane integrity (MI) and sperm abnormality (SA). Mating behaviors were monitored on days 3, 5 and 8. Blood samples, for hormonal (Luteinizing Hormone (LH), Follicle Stimulating Hormone (FSH) Testosterone (TEST) and stress analysis (heterophil/lymphocyte ratio, H/L) were collected from brachial vein on days 7 and 14. On day 15, cocks were euthanized and testes harvested for histomorphometry. Data were analyzed using multivariate analysis, one-way ANOVA and Kruskal-Wallis tests all in SPSS 23. Administration of 4 mgeCORT/KgBW declined (P<0.05) PSM while 4 mgeCORT/KgBW and 6 mgeCORT/KgBW cocks had reduced (P<0.05) SV and MI with increased SA. Compared to baseline values, progressive sperm motility of cocks administered 6 mgeCORT for 7 and 14 days decreased (P<0.05) by 57.5% and 52.4%, respectively. Exogenous CORT had no significant (P>0.05) influence on the mating behaviors, H/L ratio, FSH and TEST. However, 2 mgeCORT/KgBW enhanced LH levels. Administration of eCORT did not affect the testicular epithelial height and seminiferous tubular diameter. In conclusion, optimal stress induced by eCORT impaired semen quality but with less impact on reproductive hormones, H/L and mating behaviors of intensively raised Nigerian indigenous cocks.

The prognostic value of cyclin D1 in breast cancer patients treated with hormonal therapy: A pilot study.

THE AIM: of the study was to determine the clinical relevance of cyclin D1 (cD1) and its association with clinicopathological parameters in breast cancer patients treated with hormonal therapy. MATERIAL AND METHODS: The study included 96 primary breast cancer patients with known clinicopathological parameters. In adjuvant setting, 44 patients were tamoxifen-treated and 52 were treated with ovarian irradiation/ablation. The cD1 status (gene amplified/nonamplified) was determined on formalin-fixed paraffin-embedded tumor tissue sections by chromogenic in situ hybridization. Associations between parameters were analyzed by Chi-square and Spearman's rank order correlation tests. Cox proportional hazards regression test was performed. Survival curves for relapse-free survival were constructed according to the Kaplan-Meier method. RESULTS: There were no significant associations between cyclin D1 and clinicopathological parameters in either patient group. Amplified cyclin D1 associated significantly with the actual relapse incidence in the ovarian ablation patient group (p = 0.01, HR = 3.1), but not in the tamoxifen-treated patient group. Estrogen receptor and cyclin D1 have proven to be independent parameters of poor outcome in the ovarian ablation patient group (p = 0.03, HR = 2.9; and p = 0.009, HR = 2.5; respectively). CONCLUSIONS: Cyclin D1 might be a candidate biomarker of poor outcome in breast cancer patients treated with ovarian ablation, suggesting its possible involvement in acquirement of hormonal resistance. The role of cyclin D1 as potential parameter of response to tamoxifen was not as pronounced.

Behaviour and reproductive performance of Nigerian native chickens subjected to different mating ratios for a short term.

To date, there is no reported standard mating ratio for Nigerian native chickens despite their large population in the country. This study investigated the effect of mating ratio on behaviour, semen quality and level of stress. Sixty-three (9 cocks and 54 hens) sexually matured birds were randomly assigned to three mating ratios (MR) of 1 cock to 3 hens (1C:3H), 1 cock to 6 hens (1C:6H) and 1 cock to 9 hens (1C:9H), and each MR was replicated three times. Each cock spent 2 weeks in a particular MR before it was moved to another. By the 6th week, all cocks had experienced the three mating ratios. Behaviour of the hens and sexual behaviour of the cocks were observed in the morning and evening, respectively, for 6 weeks. At the end of 2nd week in each MR, semen samples were collected and evaluated for motility, morphology, liveability and concentration, and blood samples were also taken from the cocks to determine the heterophil/lymphocyte (H:L) ratio, an indicator of stress. There was also no significant effect of mating ratio on the fertility of eggs and hatchability of the chicks. The number of hen-hen aggression instances, frequency of visits to the nest box and duration of nesting was not influenced by the mating ratio. However, the duration of nest seeking was higher at 1C:3H and lower at 1C:9H. A mating ratio of 1C:9H is therefore recommended for farmers interested in raising Nigerian native chickens.

WITHDRAWN:Genetic diversity and effect of selection at the mitochondrial hypervariable region in major Nigerian indigenous goat breeds.

Mitochondrial DNA (mtDNA) hypervariable region 1 ( HV1) sequences of three Nigerian indigenous goat breeds; West African Dwarf (WAD), Red Sokoto (RS) and Sahel were used to investigate the genetic diversity and effect of selection between and among these populations. Deoxyribonucleic acid (DNA) of Nigerian indigenous chicken was extracted from blood samples collected and preserved on Fast Technology for Analysis (FTA) paper. The extracted DNA were amplified and sequenced with predefined mitochondria (mtDNA) primer sets for HV1. Eighty-seven (87) polymorphic sites were found in 115 sequences which were grouped into 92 haplotypes. The mean haplotypic and nucleotide diversity were found to be 0.996±0.002 and 0.092±0.04 respectively. Genetic variation within population and between populations accounted for 97.26% and 2.74% of the total maternal variation respectively, with FST value of 0.0274. The Tajima's (D) and Fu's (F) test of neutrality were significant (P<0.05) and negative with the mean value of -1.12 and -21.34 respectively which is an indication of population expansion. The result further revealed that the WAD and RS goats are closely related with less genetic distance value of 0.01, and high genetic distance value (0.02) was observed between RS and Sahel goats and WAD and Sahel goats. Selection analysis result shows that there is more positive selection site (6 sites) to negative site (5 sites) among the Nigerian goats, which signifies how diverse they are as well as how nature has being trying to confer genetic fitness to these breeds.