This study examined the effects of increased salinity on growth, development and survival of the Green toad, Bufotes variabilis during embryonic, hatching and early larval periods. Eggs from a single cohort of B. vari...This study examined the effects of increased salinity on growth, development and survival of the Green toad, Bufotes variabilis during embryonic, hatching and early larval periods. Eggs from a single cohort of B. variabilis were subjected to acute and chronic toxicity tests for water salinity ranging from 0.20 to 10 g of salt per liter. Results obtained from this study showed that salinity over 3.70 g/l increased embryonic mortality and reduced percentage of hatching and survival rate of larvae. As larvae tolerated salinity 0.20 to 3.70 g/l with highest survival, but salinity of 10 g/l caused mortality of all individuals within 12 h, 7.70-8.70 （g/l） within 4.5 days, 5.70-6.70 g/l within 10 days and 4.70 （g/l） were tolerated within 14 days. Salinity less than 0.70 g/l did not affect survival and hatching success of the embryos. After a 3-week experiment, size of larvae exposed to salinities over 0.70 g/l was lower compared to larvae reared at lower salinity levels. Meanwhile increases in salinity more than 3.70 g/l caused extension in the hatching period. Larvae reared at salinity of 3.70 to 4.70 g/l had morphological abnormalities, such as distortion of tail.展开更多
Presence of the red leg syndrome （RLS） was documented through bacterial and histological examinations in the endangered Kaiser＇s mountain newt Neurergus kaiseri obtained from a pet shop. The individuals which were ...Presence of the red leg syndrome （RLS） was documented through bacterial and histological examinations in the endangered Kaiser＇s mountain newt Neurergus kaiseri obtained from a pet shop. The individuals which were severely infected showed lethargy, appetite loss, weight loss, abdominal skin redness and skin ulcers on hind legs. This study reveals the presence of two bacteria causing RLS on the skin of captive AT. kaiseri including Proteus vulgaris and Bacillus cereus. Sections of skin in affected areas and internal organs were examined through standard histological procedures. Histologically, epidermal necrosis and ulcers, epidermal gland depletion, myositis and subcutaneous edema, gastric submucosal edema and hepatomegaly were seen. There were also correlations between the microbial infection and structural changes in tissues of Kaiser＇s mountain newt. The severity of the structural changes are related to the level of microbial infection in the target organs and could be sustained by the isolation of P. vulgaris and other pathogens. The presence of the infective bacterial population and their interaction on the skin of the newt may have changed the normal skin flora and facilitate the prevalence of other disease.展开更多
This study deals with the histomorphology of the mesonephros in male and female Neurergus microspilotus. The slender and narrow kidneys are positioned in the retro peritoneal position up against the ventral aspect of ...This study deals with the histomorphology of the mesonephros in male and female Neurergus microspilotus. The slender and narrow kidneys are positioned in the retro peritoneal position up against the ventral aspect of vertebral column and may extend the length from the esophagus-stomach junction to cloaca. The kidney in both sexes is composed of sexual（anterior） and pelvic（posterior） parts. The duct of sexual kidney is a narrow duct which is lying alongside its lateral edge. In the female, it is connected to the ureters and then the duct of defi nitive kidney. Before entering the cloaca, two ureters are joined together and open to the apex of the cloaca. In the male, after entering the sexual kidney, the sperm leave the testis through efferent ducts, then these ducts join together and eventually form Bidder＇s duct. The Bidder＇s duct joins the Bowman＇s capsule of the nephrons in the sexual kidney and the nephrons make collecting ducts which are fi lled with both sperm and urine. After leaving the kidney, all the collecting ducts are connected to the Wolffi an duct. Wolffi an duct joins the ureters（merge from defi nitive kidney） just before entering the cloaca. Based on serial paraffi n sections, nephrons consist of a fi ltration unit, the Malpighian corpuscle, and a renal tubule, which can be divided into 4 morphologically distinct segments： proximal tubule（first and second segment）, distal tubule, and collecting tubule. Collecting tubules merge and form a branch system that opens into collecting ducts.展开更多
基金the Razi University for the support of this study as an MSc research project
文摘This study examined the effects of increased salinity on growth, development and survival of the Green toad, Bufotes variabilis during embryonic, hatching and early larval periods. Eggs from a single cohort of B. variabilis were subjected to acute and chronic toxicity tests for water salinity ranging from 0.20 to 10 g of salt per liter. Results obtained from this study showed that salinity over 3.70 g/l increased embryonic mortality and reduced percentage of hatching and survival rate of larvae. As larvae tolerated salinity 0.20 to 3.70 g/l with highest survival, but salinity of 10 g/l caused mortality of all individuals within 12 h, 7.70-8.70 （g/l） within 4.5 days, 5.70-6.70 g/l within 10 days and 4.70 （g/l） were tolerated within 14 days. Salinity less than 0.70 g/l did not affect survival and hatching success of the embryos. After a 3-week experiment, size of larvae exposed to salinities over 0.70 g/l was lower compared to larvae reared at lower salinity levels. Meanwhile increases in salinity more than 3.70 g/l caused extension in the hatching period. Larvae reared at salinity of 3.70 to 4.70 g/l had morphological abnormalities, such as distortion of tail.
基金Razi University and the Iran National Science Foundation (Contract No. 91057377) that financially supported this study as a part of a PhD research project
文摘Presence of the red leg syndrome （RLS） was documented through bacterial and histological examinations in the endangered Kaiser＇s mountain newt Neurergus kaiseri obtained from a pet shop. The individuals which were severely infected showed lethargy, appetite loss, weight loss, abdominal skin redness and skin ulcers on hind legs. This study reveals the presence of two bacteria causing RLS on the skin of captive AT. kaiseri including Proteus vulgaris and Bacillus cereus. Sections of skin in affected areas and internal organs were examined through standard histological procedures. Histologically, epidermal necrosis and ulcers, epidermal gland depletion, myositis and subcutaneous edema, gastric submucosal edema and hepatomegaly were seen. There were also correlations between the microbial infection and structural changes in tissues of Kaiser＇s mountain newt. The severity of the structural changes are related to the level of microbial infection in the target organs and could be sustained by the isolation of P. vulgaris and other pathogens. The presence of the infective bacterial population and their interaction on the skin of the newt may have changed the normal skin flora and facilitate the prevalence of other disease.
文摘This study deals with the histomorphology of the mesonephros in male and female Neurergus microspilotus. The slender and narrow kidneys are positioned in the retro peritoneal position up against the ventral aspect of vertebral column and may extend the length from the esophagus-stomach junction to cloaca. The kidney in both sexes is composed of sexual（anterior） and pelvic（posterior） parts. The duct of sexual kidney is a narrow duct which is lying alongside its lateral edge. In the female, it is connected to the ureters and then the duct of defi nitive kidney. Before entering the cloaca, two ureters are joined together and open to the apex of the cloaca. In the male, after entering the sexual kidney, the sperm leave the testis through efferent ducts, then these ducts join together and eventually form Bidder＇s duct. The Bidder＇s duct joins the Bowman＇s capsule of the nephrons in the sexual kidney and the nephrons make collecting ducts which are fi lled with both sperm and urine. After leaving the kidney, all the collecting ducts are connected to the Wolffi an duct. Wolffi an duct joins the ureters（merge from defi nitive kidney） just before entering the cloaca. Based on serial paraffi n sections, nephrons consist of a fi ltration unit, the Malpighian corpuscle, and a renal tubule, which can be divided into 4 morphologically distinct segments： proximal tubule（first and second segment）, distal tubule, and collecting tubule. Collecting tubules merge and form a branch system that opens into collecting ducts.
