ABSTRACT
There has been a recent emphasis on production of large-sized Eriocheir sinensis broodstock. In China, aquaculturists generally prefer wild-caught (WC) crabs from the Yangtze River as broodstock because offspring performance is superior to that of pond-reared (PR) broodstock. Currently, however, there is a ban on fishing in the Yangtze River, and effects on E. sinensis breeding have not been ascertained. There was comparison in the present study of reproductive performance and semen characteristics of male broodstock of PR and WC groups. After copulation, sperm quantity in the vas deferens of crabs in specimens of both groups was large, although there was a consistent decrease in vaso-somatic index. Although sperm density of PR crabs was less, that of WC specimens remained relatively constant. Specimens of neither group, however, had changes in the hepatopancreas index or condition factor, and sperm survival was close to 100%. Although the acrosome reaction was detected in response to cold-temperature induction, there were differences in extent of reaction to cold temperatures. Importantly, in as many as 98% of sperm from female spermathecae, the reaction was completed, which was considerably greater than 15% for sperm of males post-mating. It is concluded there was no difference between PR and WC crabs with respect to reproductive performance or semen characteristics, and, notably, sperm from PR crabs were of sufficient quality for use in E. sinensis aquaculture enterprises. Accordingly, it is predicted the Yangtze River fishing ban would only have a limited effect on supply of male E. sinensis broodstock.
Subject(s)
Animal Husbandry , Brachyura/physiology , Animals , Animals, Wild , Body Size , Male , Reproduction/physiology , Semen , Semen AnalysisABSTRACT
Background: There is still controversy whether the existence of esophageal heterotopic gastric mucosa (EHGM) and its histological type are related to the laryngopharyngeal symptoms. Aims: To analyze the clinical and histological characteristics of EHGM and its correlation with gastroesophageal reflux. Methods: A retrospective study was conducted in consecutive gastroscopy-proved EHGM cases from September 2018 to January 2020 at the Second Affiliated Hospital of Baotou Medical College. Besides clinical data review and questionnaire survey on reflux symptoms, histological typing of EHGM and immunohistochemistry were also performed in some cases. Results: A total of 1 229 cases of EHGM were recruited. The male-to-female ratio was 1.67:1, and middle-aged people were predominant. Most of the heterotopic mucosa were located 15-18 cm away from the incisors, and were mainly single. Two hundred and ninety-four cases (23.9%) were complicated with reflux esophagitis (RE), of which Los Angeles grade A and B accounted for 96.6%. Regurgitation/acid reflux (15.5 %) and heartburn (12.3%) were the most common esophageal symptoms, while extraesophageal symptoms were rare. Histological typing was obtained in 57 cases, of which, 37 (64.9%) were cardia-type, 18 (31.6%) were fundic-type, and 2 (3.5%) were mixed type. There were no significant differences in gender, age, location and number of EHGM, expression levels of H
