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61.
While stocking floodplain depressions or beels with fingerlings is a common form of fisheries management in Bangladesh, bio‐economic guidance for improving the outcome of stocking strategies is sparse. The Community‐Based Fisheries Management (CBFM) Project, funded by the Ford Foundation and the UK Government's Department for International Development (DfID) promoted stocking practices in beels throughout the country as a means to improve fisher livelihoods. This paper describes an empirical bio‐economic model developed using data generated under the CBFM project. The model offers guidance on selecting stocking densities depending upon the available size (length) of fingerlings to maximize profit and return on investment while minimizing risk. Because large fingerlings are relatively inexpensive and have lower rates of natural mortality, the model predicts that it is more profitable to stock large fingerlings at low densities than small fingerlings at high densities. These general recommendations were found to be largely insensitive to the market price for harvested fish. To minimize credit burden and financial risk, minimum stocking densities should be selected according to the length of fish available that maximizes profit. Because of its empirical nature, the model recommendations may not be applicable beyond the project sites. Furthermore, it is recommended that attempts be made to field test the model predictions before widespread adoption or promotion.  相似文献   
62.
63.
The aim of this study was to determine the serum concentrations, ovarian presence and expression of anti‐Müllerian hormone (AMH) in pre‐pubertal, bitches with signs of ovarian remnant syndrome (ORS) and intact bitches. In addition, we aimed to verify the suitability of serum AMH concentrations for diagnostic purposes in sterilized bitches and/or in suspected cases of ORS in the field of veterinary medicine. For this purpose, 36 healthy female dogs divided into six groups: proestrus, oestrus, dioestrus, anoestrus, pre‐pubertal and ORS. Serum AMH concentrations were determined by electrochemiluminescence immunoassay, and ovarian presence and distribution of AMH was confirmed by immunohistochemical and qPCR techniques. According to the results of qPCR, while the expression values of AMH were at the highest concentrations in the proestrus and oestrus, there was a statistically significant decrease in these values at the later stages of the cycle (p < 0.05). According to hormone analysis, the serum AMH values of the ORS group had decreased significantly compared with the proestrus and oestrus (p < 0.05). Although serum AMH levels of ORS group were increased compared with anestrus and pre‐pubertal groups, this increase was statistically non‐significant (p > 0.05). Immunohistochemically, AMH expression was first observed in the granulosa cells of primordial follicles in folliculogenesis. Expression values were the highest in the proestrous and oestrus groups, but values from bitches in later stages of the cycle were statistically significant decrease in comparison with these groups (p < 0.05). As a result, AMH concentration and expression were found to be higher in proestrus and oestrus than in other periods (p < 0.05). In addition, the measurable level of AMH concentration in bitches with ORS is an indication that it can be used in the diagnosis of ORS.  相似文献   
64.
Variations in digestive enzymes and hormones during the larval development of gilthead seabream (Sparus aurata) fed on live prey (Artemia nauplii) enriched with free lysine were investigated for 16 days (from day 24 to day 40). Prior to initiation of the experiment, newly hatched larvae were transferred from incubators to fiber glass tanks (300 l) with black walls and fed the same diet until day 24. Each experiment was performed in triplicate. The amount of free lysine in the Artemia nauplii was increased by adding a 5.3 mM free amino acid solution to the culture water during a 16-h enrichment period. Larvae were sampled four times at four-day intervals, for 16 days. Larvae fed on the control group had lower growth than those fed on the lysine group at the end of the study but the difference was not significant (P > 0.05). The highest trypsin activity and lap/leu–ala peptidase ratios were observed in the control group (P < 0.05). Significant differences between bombesin activities of the treatment groups were not found in the fifth minute after the start of feeding (P > 0.05) but were significant in the fifteenth minute (P < 0.05). Significant differences between the CCK levels of the treatment groups were found (P < 0.05). In conclusion, three main ideas are presented in this study. First, Artemia nauplii can successfully be enriched with free lysine. Second, bombesin (GRP) and cholecystokinin (CCK) activity can be stimulated by free lysine. Third, the mechanisms controlling adaptation of the activity of the trypsin to the amount of dietary protein were not activated until day 40.  相似文献   
65.
Irisin, a novel peptide, was initially been shown to be expressed explicitly in the muscle tissues. We studied the presence of irisin immunoreactivity in porcupine adrenal glands and kidneys. Immunocytochemistry showed that irisin was localised both in the adrenal cortex and adrenal medulla. In organs, irisin immunoreactivity was found in the tubular and collecting system of the nephron. The functional role of irisin in the adrenal gland and kidney has not been precisely yet. However, irisin might have a paracrine and autocrine function as do other locally produced peptides.  相似文献   
66.
The effects of abamectin (AVMB1) on intracellular potassium ion activity (aKi) and resting membrane potential (Em) of the skeletal muscle cells of final instar larvae of Phormia terraenovae (Diptera) were investigated using K+-selective micro-electrodes. Bathing the preparation in 10? M AVMB1(+ 1 ml litre?1 dimethylsulfoxide) for 60 min caused a significant (31%) decrease in aKi, whilst Em depolarized on average by 19 mV (nearly 50% of the original control value). The difference EK-Em increased by 9 mV, although EK (potassium equilibrium potential) remained more negative than Em. These results could be due to a cationic effect of AVMB1 possibly involving an increase in K+ and Na+ conductances of the muscle plasma membrane.  相似文献   
67.
Ostriches lack meibom glands, but have small lacrimal glands ventral to the lateral canthus, with ductules that open into the inside of the lower eyelid. Chalazion is a chronic granulomatous inflammation of the meibom glands that may develop from blockage of the ductules into the conjunctiva. A 2-year-old female ostrich presented with chronic granulomatous conjunctivitis, with clinical and histopathologic findings similar to chalazion of other species. The granulomatous dacryoadenitic mass was excised and no recurrence occurred at 4 months. This is the first case of chronic granulomatous conjunctivitis reported in the ostrich.  相似文献   
68.
The proximal caecum in quails consists of lymphoid and non‐lymphoid structures. The caecal tonsils in the proximal part of the caecum are units of gut‐associated lymphoid tissue in poultry. This study aimed to examine the histological characteristics of the proximal caecum, as well as compositions of dendritic cells (DCs) and antigen‐presenting cells (APCs) in the caecal tonsil of quails. Tissue sections were stained with Crossman's triple, periodic acid–Schiff, Gordon and Sweet's silver, Congo red and methyl green‐pyronin dyes, as well as immunohistochemically by the streptavidin–biotin–peroxidase complex method. Caecal lymphoid tissue was located in the lamina propria and submucosa. Germinative centres were observed within the lymphoid tissue. Reticular fibres were mainly distributed in the border area of the germinal centre with only a few fibres scattered in the centre. Plasma cells were observed in the subepithelial region and germinal centres. Eosinophil granulocytes were prevalent in the lymphoid tissue. Additionally, CD83‐immunoreactive DCs and MHC class II immunoreactive APCs were present in the subepithelial area and diffuse lymphoid tissue. While DCs were seen in the germinal centres of tonsillar units, APCs were rarely present in the germinal centres, but they were noticed around the germinal centres. In conclusion, the histological structure of the proximal caecum in quails and the distributions of some immunological cells in the caecal tonsils were revealed. Therefore, the defensive role of the caecal tonsils in the digestive system may be better understood, and comparative studies may be carried out.  相似文献   
69.
In this study, phytochemical and antioxidant properties of anthocyanin-rich mulberry species of Morus nigra L. (black mulberry) and Morus rubra L. (red mulberry) fruits harvested from across Turkey were investigated. Fruit color, total phenolics (TP), total monomeric anthocyanin (TMA), titratable acidity (TA), and individual sugar and organic acid compositions were determined. Total antioxidant capacity (TAC) of fruits was assessed by both the trolox-equivalent antioxidant capacity (TEAC) and the ferric reducing antioxidant power (FRAP) assays. Black mulberry exhibited higher TP, TMA, TAC and TA when compared to red mulberry. The average TP contents of M. nigra and M. rubra were 2737 and 1603 μg gallic acid equivalent in g fresh weight basis (GAE/g fw), respectively. M. nigra had the richest amount of anthocyanin with an average of 571 μg cy-3-glu/g fw. Overall, TAC averaged 10.5 and 12.0 mmol TE/L by the TEAC and FRAP methods, respectively. We found that FRAP, TEAC, TP and TMA were significantly correlated (r = 0.64–0.99) with each other. Fructose (5.27 g/100 mL) and glucose (5.81 g/100 mL) were determined to be the major sugars in both mulberries. M. nigra displayed a higher TA (2.05 g/100 mL) than M. rubra (0.78 g/100 mL), with citric acid as the major acid.  相似文献   
70.
The prevalence of Dirofilaria immitis infection was evaluated in stray dogs of Erzurum, Turkey. A total of 123 whole-blood and 93 sera samples were collected from stray dogs older than 6 months were lived in animal shelter. The PCR and direct microscopic examinations were used for the detection of microfilaria and indirect-ELISA was performed for the detection of anti-D. immitis antibodies. The prevalence of D. immitis in the canine population was 8.1% by PCR, 2.1% by ELISA. In addition, microfilaria burdens of Dirofilaria sp. was 4.8% by direct blood smear examination. There was a statistical difference (P=0.05) in the prevalence between males (10.5%) and females (2.3%) by direct blood smear examination. Similarly there was a statistical difference (P<0.05) in the prevalence between males (15.8%) and females (4.7%) by PCR. Dogs belonging to the 0.5-1 years old group showed the highest prevalence than 2-4 ages group with three tests. Among the 93 samples screened by the ELISA, two samples were positive for the D. immitis antibodies. Both positive dogs with ELISA were females.  相似文献   
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