17α-Methyltestosterone enhances growth and reproductive performance of immature male Asian catfish (Clarias macrocephalus)

This study aimed to assess the effects of 17α-methyltestosterone (MT) on the growth and reproductive performance of male Asian catfish (Clarias macrocephalus). A total of 36 immature male Asian catfish (ABW = 125.97 g) were randomly distributed into 12 circular tanks, and fed with either the control diet (with no MT) or diets containing MT at 60 mg·kg-1, 90 mg·kg-1, or 120 mg·kg-1 for 45 days. Results showed that weight gain (WG), specific growth rate (SGR) and feed intake (FI) were significantly higher in the male catfish fed with diets containing 60 and 90 mg·kg-1 MT than in those fed with the control diet. Also, the diet attractability test revealed that the 60 and 90 mg·kg-1 MT groups significantly attracted more catfish than did the control diet; however, increasing MT to 120 mg·kg-1 reduced its attractability to the immature male catfish. MT-treated male catfish exhibited significantly heavier and significantly longer testes than male catfish fed the control diet at the termination of the feeding trial. These male catfish also exhibited significantly higher gonadosomatic indices (GSI) than catfish in the control group. Following induced spawning of nontreated female catfish and artificial fertilization of its eggs using testis preparation from the experimental male catfish at the termination of the feeding trial, results showed that testis preparations from all MT-treated males resulted in significantly higher fertilization (FR) and hatching rates (HR) of the eggs. In conclusion, incorporating MT to the diet improved both the growth and reproductive performance of the male Clarias macrocephalus. Precisely, dosages of optimal dietary MT using a quadratic model for maximal SGR, GSI, FR, and HR values were estimated to be 58.3, 75.0, 90.6, and 78.2 mg·kg-1, respectively

Dietary DL-alpha-tocopheryl acetate enhances growth, survival, and resistance against an abrupt shift to higher salinity of the Asian catfish (Clarias macrocephalus) fry

The effect of dietary supplementation of DL-alpha-tocopheryl acetate (a-TA) on growth performance, feed efficiency, survival, and salinity resistance of Asian catfish (Clarias macrocephalus) fry was evaluated. A total of 750 catfish fry were divided into five treatments with three replicates and fed experimental diets containing varying levels of alpha-TA: 0, 100, 200, 300, and 400 mg·kg-1 diet for 45 days. Results show that catfish fry-fed diets supplemented with alpha-TA exhibited significantly higher weight gain (WG) and final average body weight (FABW), better specific growth rates (SGR) and feed conversion ratio (FCR), and significantly higher survival rates compared to those of the control group fed the basal diet (P < 0.05). Better salinity resistance was observed in the Asian catfish fed the alpha-TA-supplemented diets when abruptly exposed to higher salinity (10 ppt) for up to 48 h. In addition, the diet attractability test revealed that alpha-TA-supplemented diets attracted significantly more catfish fry than the basal diet lacking vitamin E (P < 0.05). In conclusion, the results demonstrated that dietary supplementation of alpha-TA (vitamin E) improved growth, feed efficiency, feed attractability, survival, and resistance to abrupt higher salinity exposure of Clarias macrocephalus fry

Effects of vitamin E on growth and maturation in the Asian catfish (Clarias macrocephalus) at puberty

The maturation of male fish is a problematic aspect of Clarias macrocephalus and probably one of the causes of the population's disappearance in the usual places where they once abound. The present study aimed to explore feed additives to enhance its maturation from puberty. Vitamin E (VE) is essential in the reproduction of animals, including fish. A growth trial was conducted in which groups of C. macrocephalus were fed experimental diets containing graded levels of VE in the form of α-tocopheryl acetate (α-TA), namely, 0, 100, 200, 300 and 400 mg VE·kg-1 diet. After 90 days, growth and maturation were assessed, and reproductive performance was tested by conducting induced spawning and artificial fertilization. Results showed growth and nutrient utilization indices were better in groups fed diets containing VE than in the control group. Maturation indices such as GSI, gonad weight, lengths, egg diameter, and fecundity were enhanced in the VE-treated groups. Reproductive performance, such as fertilization, hatching, and larval survival rate, was enhanced in C. macrocephalus broodstock in VE-treated groups. Quantitative estimates for optimal VE dose that elicited maximal response values ranged from 202.1 to 230.0 mg VE·kg-1 diet

Benfotiamine in high carbohydrate diet enhances growth and reproductive performance of the Asian native catfish Clarias macrocephalus subadults

Clarias macrocephalus has been extirpated in most regions in the Philippines and as a preliminary study towards its reintroduction, we aimed at enhancing the growth and reproductive performance of the broodstock. Several studies have identified thiamine deficiency as a factor in the extirpation of some important fish species in the wild. The present study aimed to determine the effects of elevated dietary carbohydrates and benfotiamine, a more bioavailable analog of thiamine (vitamin B1). Three diets were used, namely, a commercial diet specific for catfish was used as the control diet (Com), a high carbohydrate (HC) diet, and a benfotiamine-supplemented HC diet (HCB). Results show that survival of the subadult catfish in captivity for 10 weeks was remarkably high, exhibiting an average of 99% for all three treatments (P>0.05). HCB diet resulted in significantly higher final average body weight (FABW), weight gain (WG), specific growth rate (SGR), and significantly best food conversion ratio (FCR) (P0.05). For the reproductive performance, female Asian catfish fed the HCB diet exhibited significantly heavier ovary and liver (P0.05). GSI of the female catfish and fecundity were significantly higher in the HCB group (P0.05). In the male catfish, testes were significantly heavier in the HCB group (P0.05). HSI, male LW, and LL were significantly higher in the HC and HCB groups (P>0.05) than in the Com group (P0.05). In conclusion, elevating dietary carbohydrates in the diet from 7.70% to 22.73% (i.e., Com to HC diet, respectively) did not negatively affect the growth and reproductive performance of the Asian catfish. Further supplementation of benfotiamine at 0.02% to the HC diet enhanced significantly both the growth and reproductive performance of the Asian catfish

Morpho-molecular ex vivo detection and grading of non-muscle-invasive bladder cancer using forward imaging probe based multimodal optical coherence tomography and Raman spectroscopy

Non-muscle-invasive bladder cancer affects millions of people worldwide, resulting in significant discomfort to the patient and potential death. Today, cystoscopy is the gold standard for bladder cancer assessment, using white light endoscopy to detect tumor suspected lesion areas, followed by resection of these areas and subsequent histopathological evaluation. Not only does the pathological examination take days, but due to the invasive nature, the performed biopsy can result in significant harm to the patient. Nowadays, optical modalities, such as optical coherence tomography (OCT) and Raman spectroscopy (RS), have proven to detect cancer in real time and can provide more detailed clinical information of a lesion, e.g. its penetration depth (stage) and the differentiation of the cells (grade). In this paper, we present an ex vivo study performed with a combined piezoelectric tube-based OCT-probe and fiber optic RS-probe imaging system that allows large field-of-view imaging of bladder biopsies, using both modalities and co-registered visualization, detection and grading of cancerous bladder lesions. In the present study, 119 examined biopsies were characterized, showing that fiber-optic based OCT provides a sensitivity of 78% and a specificity of 69% for the detection of non-muscle-invasive bladder cancer, while RS, on the other hand, provides a sensitivity of 81% and a specificity of 61% for the grading of low- and high-grade tissues. Moreover, the study shows that a piezoelectric tube-based OCT probe can have significant endurance, suitable for future long-lasting in vivo applications. These results also indicate that combined OCT and RS fiber probe-based characterization offers an exciting possibility for label-free and morpho-chemical optical biopsies for bladder cancer diagnostics. © 2020 The Royal Society of Chemistry

Track D Social Science, Human Rights and Political Science

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd