The only known predictable aggregation of dwarf minke whales (Balaenoptera acutorostrata subsp.) occurs in the Australian offshore waters of the northern Great Barrier Reef in May-August each year. The identification ...The only known predictable aggregation of dwarf minke whales (Balaenoptera acutorostrata subsp.) occurs in the Australian offshore waters of the northern Great Barrier Reef in May-August each year. The identification of individual whales is required for research on the whales’ population characteristics and for monitoring the potential impacts of tourism activities, including commercial swims with the whales. At present, it is not cost-effective for researchers to manually process and analyze the tens of thousands of underwater images collated after each observation/tourist season, and a large data base of historical non-identified imagery exists. This study reports the first proof of concept for recognizing individual dwarf minke whales using the Deep Learning Convolutional Neural Networks (CNN).The “off-the-shelf” Image net-trained VGG16 CNN was used as the feature-encoder of the perpixel sematic segmentation Automatic Minke Whale Recognizer (AMWR). The most frequently photographed whale in a sample of 76 individual whales (MW1020) was identified in 179 images out of the total 1320 images provid-ed. Training and image augmentation procedures were developed to compen-sate for the small number of available images. The trained AMWR achieved 93% prediction accuracy on the testing subset of 36 positive/MW1020 and 228 negative/not-MW1020 images, where each negative image contained at least one of the other 75 whales. Furthermore on the test subset, AMWR achieved 74% precision, 80% recall, and 4% false-positive rate, making the presented approach comparable or better to other state-of-the-art individual animal recognition results.展开更多
Although four species of odontocete and four species of baleen whale have been recorded in Prydz Bay,their vocalizations have been rarely investigated.Underwater vocalizations were recorded during March 2017 in Prydz ...Although four species of odontocete and four species of baleen whale have been recorded in Prydz Bay,their vocalizations have been rarely investigated.Underwater vocalizations were recorded during March 2017 in Prydz Bay,Antarctica.Bio-duck sounds,downsweeps,inverted“u”shape signals,whistles,pulsed sounds,and broadband clicks were recorded.Bio-duck sounds and downsweeps were associated with Antarctic minke whales(Balaenoptera bonaerensis)based on visual observations.Similarities between inverted“u”shape signals,biphonic calls,and clicks with vocalizations previously described for killer whales(Orcinus orca)lead us believe the presence of Antarctic killer whales.According to sound structures,signal characteristics,and recording location,Antarctic type C killer whales were the most probable candidates to produce these detected calls.These represent the fi rst detection of inverted“u”shape signals in Antarctic waters,and the fi rst report of Antarctic killer whale in Prydz Bay based on passive acoustic monitoring.The co-existence of Antarctic minke and killer whales may imply that minke whales can detect diff erences between the sounds of mammal-eating and fi sh-eating killer whales.Our descriptions of these underwater vocalizations contribute to the limited body of information regarding the distribution and acoustic behavior of cetaceans in Prydz Bay.展开更多
Whale age at sexual maturity is one of the most important biological parameters that can be used in stock management and population analysis. Earplugs have been widely used as an indicator of age among rorquals. It ha...Whale age at sexual maturity is one of the most important biological parameters that can be used in stock management and population analysis. Earplugs have been widely used as an indicator of age among rorquals. It has also been accepted that the transition phase in the earplug can be used as an indicator of age at sexual maturity in fin whales, sei whales, and Antarctic minke whales. This study aimed to provide further insight into the utility of the transition phase as an indicator of age at sexual maturity in the North Pacific common minke whales, which has not yet been clarified. The relationship between sexual maturity and transition phase in earplugs was examined using 981 readable earplugs from common minke whales that were sampled at the JARPN and JARPN II scientific permit survey platform in the western North Pacific from 1994 to 2011. The transition phase was recognized in 53.2% of mature males and in 58.6% of mature females. Most whales in which the transition phase was recognized in the earplug were sexually mature. A significant correlation was found between the number of corpora and time after sexual maturation, as revealed by the transition phase, demonstrating that the transition phase is a valid indicator of age at sexual maturity in common minke whales. However, it was difficult to recognize the transition phase in whales that had recently attained sexual maturity because insufficient time had elapsed since its formation. To avoid potential bias, the use of earplugs as an indicator of age should be restricted to whales more than 12 years old.展开更多
Little is known about the morphology of the pelvic girdle of modern cetaceans, although many species have a vestigial pelvis (pelvic bone) and part of the hind limb bones inside the body. Previous studies have focused...Little is known about the morphology of the pelvic girdle of modern cetaceans, although many species have a vestigial pelvis (pelvic bone) and part of the hind limb bones inside the body. Previous studies have focused almost exclusively on hard tissues as well, despite the fact that the bones are comprised of cartilaginous tissue, especially in the case of femur. In the present study, we characterized the pelvic bones and searched for vestigial femurs among 43 North Pacific common minke whales (Balaenoptera acutorostrata), all of which were sexually mature individuals. The shape of the pelvic bones clearly differs depending on sex. Specifically, the pelvic bones of females were flat, but those of adult males consist of two types: one with a twisted caudal portion (Twisted type) and the other with a thickened caudal portion (Hypertrophied type). Those pelvic bone features in male are found only among North Pacific common minke whales. 98% of the individuals in this study had vestigial femur. The presence rate of vestigial femur may differ by subspecies. The shape of the pelvic and hind limb bones of modern cetaceans may vary between species and probably by region, at least at the Ocean basin scale.展开更多
Past studies have indicated that there are two different stocks (J and O stocks) in the North Pacific common minke whale Balaenoptera acutorostrata population. These two stocks differ from each other in certain charac...Past studies have indicated that there are two different stocks (J and O stocks) in the North Pacific common minke whale Balaenoptera acutorostrata population. These two stocks differ from each other in certain characteristics, such as body size, conception dates, and genetics. However, till date, few studies have investigated differences in the external body appearance between the two stocks. Therefore, in the present study, we focused on the unique white patch on the flipper of this whale species to elucidate inter-stock differences. We used the animals collected from JARPNII research during 2012 and 2013;stock information was determined by microsatellite DNA analysis (n = 220). We focused on the morphological differences in the size and pattern of the white patch on the flipper of each whale. The length of the white patch along the anterior (ventral) margin of the flipper tends to be proportionally larger in O stock. The pattern of the boundary area of the white patch named as the “Grayish Accessary Layer (GAL)” was remarkably different between stocks. Within animals with “no GAL” type, 94% were J stock. Conversely, of animals with GAL expanding over the half the flipper width, 96% were O stock. We concluded from our study that there were clear morphological differences in the flipper color pattern between J and O stocks, which enable to apply widely to other individuals.展开更多
Minks are highly susceptible to SARS-CoV-2,and have transmitted SARS-CoV-2 to humans.Oral immunization is one of the most promising strategies to prevent SARS-CoV-2 infection and transmission in minks.Here,we generate...Minks are highly susceptible to SARS-CoV-2,and have transmitted SARS-CoV-2 to humans.Oral immunization is one of the most promising strategies to prevent SARS-CoV-2 infection and transmission in minks.Here,we generated 3 recombinant rabies viruses(RABV),rERAG_(333E)/S6P,rERAG_(333E)/DS6P and rERAG_(333E)/BA2S6P,expressing the prefusion-stabilized SARS-CoV-2 spike protein of wild-type(S6P),δ(DS6P)or BA.2(BA2S6P)strain based on an oral rabies vaccine candidate(rERAG_(333E)).Oral or inactivated immunization of the 3 RABVs monovalent or trivalent were safe,and induced robust RABV neutralizing antibody and cross-antibody responses against the three SARS-CoV-2 in mice and minks.The challenge tests showed that 2 doses of rERAG_(333E)-S6P as an oral or inactivated vaccine completely protected mice against mouse-adapted SARS-CoV-2 infection in the upper and lower respiratory tracts,and largely prevented viral replication and lung damage caused by wild-type SARS-CoV-2infection in minks.Notably,we also confirmed that 2 doses of rERAG_(333E)-S6P as an oral or inactivated vaccine can largely protect minks against wild-type SARS-CoV-2 transmission via respiratory droplets.Our findings suggest that rERAG_(333E)-based COVID-19 vaccines appear to be suitable oral candidates to protect minks from SARS-CoV-2infection and transmission,and may serve as inactivated vaccines for further investigation in humans.展开更多
Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very w...Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very well by Logistic model and Gompertz model （the degree of fitting FF≥0.99）, but Gompertz model was better at fitting and predicting their weight.展开更多
[Objective] This study aimed to test the sensitivity of Eperythrozoon from mink to various drugs in vitro. [Method] The red blood cells isolated from Eperythro- zoon positive mink was cultured in complete medium （70%...[Objective] This study aimed to test the sensitivity of Eperythrozoon from mink to various drugs in vitro. [Method] The red blood cells isolated from Eperythro- zoon positive mink was cultured in complete medium （70% RPMI-1640 medium and 30% calf serum）, supplemented with bernier, oxytetracycline, trichlorfon, tylosin, imi- docarb, florfenicol, Fuhongjuesha or primaquine phosphate at the working concentra- tions of 12, 24, 36, 48 and 96 μL/ml, incubated at 37.3 ℃, 5% CO2. [Result] Fuhongjuesha was most efficient for killing Eperythrozoon, followed by trichiorfon and primaquine phosphate, but trichlorfon is toxic. Bernier, imidocarb and florfenicol are efficient. [Conclusion] The study provides a scientific reference for clinical treatment of eperythrozoonosis.展开更多
[Objective] The paper was to diagnose and treat hemorrhagic pneumonia of mink. [Method] The diseased minks bred by one raiser in Huangtian Village of Changli County in Qinhuangdao City were used as experimental materi...[Objective] The paper was to diagnose and treat hemorrhagic pneumonia of mink. [Method] The diseased minks bred by one raiser in Huangtian Village of Changli County in Qinhuangdao City were used as experimental materials. It was necropsied, and its tissues such as liver, kidney, spleen and lung were taken under aseptic condition, then inoculated into general nutrition agar and blood agar. The bacteria were isolated and purified, and the strains obtained were carried out animal inoculation test and drug sensitivity test. Finally, the relevant treatment and preven- tive measures were put forward. [Conclusion] The bacteria isolated were detected to be negative by Gram staining; it formed hemolysis ring in blood agar; the bacteria could ferment glucose and xylose, which could not ferment sucrose, lactose, maltose and esculin; it was positive in catalase and oxidase test, and negative in urease test and hydrogen sulfide test; so the strain was indentified to be Pseudomonas aerugi- nosa. Drug sensitivity test showed that the bacteria were highly sensitive to ciprofloxacin, which had tolerance to cefoxitin. [Conclusion] The study laid foundation for diagnosis and treatment of hemorrhagic pneumonia of mink.展开更多
AIM： To establish a new, reliable vomit model of minks METHODS： Adult male minks were randomly divided into 8 groups （n=6）： cisplatin （7.5 mg/kg） intraperitoneal injection （ip） group, copper sulfate （40 mg/k...AIM： To establish a new, reliable vomit model of minks METHODS： Adult male minks were randomly divided into 8 groups （n=6）： cisplatin （7.5 mg/kg） intraperitoneal injection （ip） group, copper sulfate （40 mg/kg） intragastric injection （ig） group, apomorphine （1.6 mg/kg） subcutaneous injection （sc） group, and 18 Gy whole-body X-irradiation group, ondansetron injection group （2 mg/kg ip） 30 min later followed by cisplatin （7.5 mg/kg） ip, normal saline （NS） ip injection control group, metoclopramide injection group （4 mg/kg ip） 30 rain later followed by apomorphine （1.6 mg/kg） sc, NS ig control group. The frequency of retching and vomiting was calculated. After behavioral experiment, distribution of 5-HT in the ileum was detected by immunohistologic method. RESULTS： Cisplatin, apomorphine, copper sulfate and X-irradiation administered to minks evoked a profound emetic response in the animals. However, retching and vomiting were significantly inhibited by pretreatment with ondansetron and metoclopramide in cisplatin and copper sulfate groups （P=0.018）. Immunohistologic result showed that 5-HT released from enterochromaffin cells （EC cells） was involved in vomiting mechanism. CONCLUSION： Mink vomit model has a great value in studying the vomiting mechanism and screening new antiemetic drugs.展开更多
A study was conducted to evaluate production performance of minks in growing-furring period with supplementing DL-Methinnine(Met)in low protein diet.Seventy healthy male minks were randomly divided into five groups of...A study was conducted to evaluate production performance of minks in growing-furring period with supplementing DL-Methinnine(Met)in low protein diet.Seventy healthy male minks were randomly divided into five groups of 14 minks each.The minks were fed in five kinds of experiment diets(HP,LP,LP+M1,LP+M2 and LP+M3).The dietary protein levels,expressed as percentage of dry matter(DM),were 32%(high protein,HP)and 24%(low protein,LP).LP was supple-mented with Met 0.4%(M1),0.8%(M2)and 1.2%(M3)DM.From mid of September to December 10,apparent digestibility of CP(crude pro-tein),N intake and urinary N excretion were decreased with declining dietary protein levels(p〈0.05)and N retained was the highest in treat-ment LP+M2.No significant difference was found in total serum protein(TP)and serum urea nitrogen(SUN)among all treatment groups(p〉0.05).Skin length of treatment HP and LP^M2 was higher than that of other groups(p〈0.05).Body length,skin weight,length of guard hair and under hair were not affected by different dietary protein levels(p〉0.05).The best performance could be observed in treatment LP+M2.In diet,24%(DM)protein level with 1.54%Met supplementing was enough for minks during growing-farring period.Dietary protein lowered from 32%to 24%with supplementing Met in diets would result in a37.9%decrease in urinary N excretion.Furthermore,addition of Met in diets for minks would be beneficial in terms of reducing feed expenses and lessening nitrogen emissions to the environment.展开更多
Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis （BSA） in combination with RAP...Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis （BSA） in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions （SCAR） marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex （MHC） class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference （p〈0.01） in the detection rate between the two groups. This indicated that SRA8-250 can be used as a positive marker to detect self-biting disease in minks. Furthermore, the finding that self-biting disease links with MHC genes has significant implications for the mechanism of the disease.展开更多
文摘The only known predictable aggregation of dwarf minke whales (Balaenoptera acutorostrata subsp.) occurs in the Australian offshore waters of the northern Great Barrier Reef in May-August each year. The identification of individual whales is required for research on the whales’ population characteristics and for monitoring the potential impacts of tourism activities, including commercial swims with the whales. At present, it is not cost-effective for researchers to manually process and analyze the tens of thousands of underwater images collated after each observation/tourist season, and a large data base of historical non-identified imagery exists. This study reports the first proof of concept for recognizing individual dwarf minke whales using the Deep Learning Convolutional Neural Networks (CNN).The “off-the-shelf” Image net-trained VGG16 CNN was used as the feature-encoder of the perpixel sematic segmentation Automatic Minke Whale Recognizer (AMWR). The most frequently photographed whale in a sample of 76 individual whales (MW1020) was identified in 179 images out of the total 1320 images provid-ed. Training and image augmentation procedures were developed to compen-sate for the small number of available images. The trained AMWR achieved 93% prediction accuracy on the testing subset of 36 positive/MW1020 and 228 negative/not-MW1020 images, where each negative image contained at least one of the other 75 whales. Furthermore on the test subset, AMWR achieved 74% precision, 80% recall, and 4% false-positive rate, making the presented approach comparable or better to other state-of-the-art individual animal recognition results.
基金Supported by the National Natural Science Foundation of China(No.41906170)the Indian Ocean Ninety-east Ridge Ecosystem and Marine Environment Monitoring and Protection(No.DY135-E2-4)+1 种基金the Cooperation of Top Predators Observation in the Southern Ocean(No.QT4519003)the China-ASEAN Maritime Cooperation Fund。
文摘Although four species of odontocete and four species of baleen whale have been recorded in Prydz Bay,their vocalizations have been rarely investigated.Underwater vocalizations were recorded during March 2017 in Prydz Bay,Antarctica.Bio-duck sounds,downsweeps,inverted“u”shape signals,whistles,pulsed sounds,and broadband clicks were recorded.Bio-duck sounds and downsweeps were associated with Antarctic minke whales(Balaenoptera bonaerensis)based on visual observations.Similarities between inverted“u”shape signals,biphonic calls,and clicks with vocalizations previously described for killer whales(Orcinus orca)lead us believe the presence of Antarctic killer whales.According to sound structures,signal characteristics,and recording location,Antarctic type C killer whales were the most probable candidates to produce these detected calls.These represent the fi rst detection of inverted“u”shape signals in Antarctic waters,and the fi rst report of Antarctic killer whale in Prydz Bay based on passive acoustic monitoring.The co-existence of Antarctic minke and killer whales may imply that minke whales can detect diff erences between the sounds of mammal-eating and fi sh-eating killer whales.Our descriptions of these underwater vocalizations contribute to the limited body of information regarding the distribution and acoustic behavior of cetaceans in Prydz Bay.
文摘Whale age at sexual maturity is one of the most important biological parameters that can be used in stock management and population analysis. Earplugs have been widely used as an indicator of age among rorquals. It has also been accepted that the transition phase in the earplug can be used as an indicator of age at sexual maturity in fin whales, sei whales, and Antarctic minke whales. This study aimed to provide further insight into the utility of the transition phase as an indicator of age at sexual maturity in the North Pacific common minke whales, which has not yet been clarified. The relationship between sexual maturity and transition phase in earplugs was examined using 981 readable earplugs from common minke whales that were sampled at the JARPN and JARPN II scientific permit survey platform in the western North Pacific from 1994 to 2011. The transition phase was recognized in 53.2% of mature males and in 58.6% of mature females. Most whales in which the transition phase was recognized in the earplug were sexually mature. A significant correlation was found between the number of corpora and time after sexual maturation, as revealed by the transition phase, demonstrating that the transition phase is a valid indicator of age at sexual maturity in common minke whales. However, it was difficult to recognize the transition phase in whales that had recently attained sexual maturity because insufficient time had elapsed since its formation. To avoid potential bias, the use of earplugs as an indicator of age should be restricted to whales more than 12 years old.
文摘Little is known about the morphology of the pelvic girdle of modern cetaceans, although many species have a vestigial pelvis (pelvic bone) and part of the hind limb bones inside the body. Previous studies have focused almost exclusively on hard tissues as well, despite the fact that the bones are comprised of cartilaginous tissue, especially in the case of femur. In the present study, we characterized the pelvic bones and searched for vestigial femurs among 43 North Pacific common minke whales (Balaenoptera acutorostrata), all of which were sexually mature individuals. The shape of the pelvic bones clearly differs depending on sex. Specifically, the pelvic bones of females were flat, but those of adult males consist of two types: one with a twisted caudal portion (Twisted type) and the other with a thickened caudal portion (Hypertrophied type). Those pelvic bone features in male are found only among North Pacific common minke whales. 98% of the individuals in this study had vestigial femur. The presence rate of vestigial femur may differ by subspecies. The shape of the pelvic and hind limb bones of modern cetaceans may vary between species and probably by region, at least at the Ocean basin scale.
文摘Past studies have indicated that there are two different stocks (J and O stocks) in the North Pacific common minke whale Balaenoptera acutorostrata population. These two stocks differ from each other in certain characteristics, such as body size, conception dates, and genetics. However, till date, few studies have investigated differences in the external body appearance between the two stocks. Therefore, in the present study, we focused on the unique white patch on the flipper of this whale species to elucidate inter-stock differences. We used the animals collected from JARPNII research during 2012 and 2013;stock information was determined by microsatellite DNA analysis (n = 220). We focused on the morphological differences in the size and pattern of the white patch on the flipper of each whale. The length of the white patch along the anterior (ventral) margin of the flipper tends to be proportionally larger in O stock. The pattern of the boundary area of the white patch named as the “Grayish Accessary Layer (GAL)” was remarkably different between stocks. Within animals with “no GAL” type, 94% were J stock. Conversely, of animals with GAL expanding over the half the flipper width, 96% were O stock. We concluded from our study that there were clear morphological differences in the flipper color pattern between J and O stocks, which enable to apply widely to other individuals.
基金supported by the National Key Research and Development Program of China(2021YFC2301700)the Natural Science Foundation of Heilongjiang Province,China(YQ2022C040)。
文摘Minks are highly susceptible to SARS-CoV-2,and have transmitted SARS-CoV-2 to humans.Oral immunization is one of the most promising strategies to prevent SARS-CoV-2 infection and transmission in minks.Here,we generated 3 recombinant rabies viruses(RABV),rERAG_(333E)/S6P,rERAG_(333E)/DS6P and rERAG_(333E)/BA2S6P,expressing the prefusion-stabilized SARS-CoV-2 spike protein of wild-type(S6P),δ(DS6P)or BA.2(BA2S6P)strain based on an oral rabies vaccine candidate(rERAG_(333E)).Oral or inactivated immunization of the 3 RABVs monovalent or trivalent were safe,and induced robust RABV neutralizing antibody and cross-antibody responses against the three SARS-CoV-2 in mice and minks.The challenge tests showed that 2 doses of rERAG_(333E)-S6P as an oral or inactivated vaccine completely protected mice against mouse-adapted SARS-CoV-2 infection in the upper and lower respiratory tracts,and largely prevented viral replication and lung damage caused by wild-type SARS-CoV-2infection in minks.Notably,we also confirmed that 2 doses of rERAG_(333E)-S6P as an oral or inactivated vaccine can largely protect minks against wild-type SARS-CoV-2 transmission via respiratory droplets.Our findings suggest that rERAG_(333E)-based COVID-19 vaccines appear to be suitable oral candidates to protect minks from SARS-CoV-2infection and transmission,and may serve as inactivated vaccines for further investigation in humans.
基金Supported by Foundation for Innovation Team of Special Animal Genetic Resources of Chinese Academy of Agricultural Sciences~~
文摘Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very well by Logistic model and Gompertz model （the degree of fitting FF≥0.99）, but Gompertz model was better at fitting and predicting their weight.
基金Supported by Fund of Hebei Science and Technology Department(10960408D01)~~
文摘[Objective] This study aimed to test the sensitivity of Eperythrozoon from mink to various drugs in vitro. [Method] The red blood cells isolated from Eperythro- zoon positive mink was cultured in complete medium （70% RPMI-1640 medium and 30% calf serum）, supplemented with bernier, oxytetracycline, trichlorfon, tylosin, imi- docarb, florfenicol, Fuhongjuesha or primaquine phosphate at the working concentra- tions of 12, 24, 36, 48 and 96 μL/ml, incubated at 37.3 ℃, 5% CO2. [Result] Fuhongjuesha was most efficient for killing Eperythrozoon, followed by trichiorfon and primaquine phosphate, but trichlorfon is toxic. Bernier, imidocarb and florfenicol are efficient. [Conclusion] The study provides a scientific reference for clinical treatment of eperythrozoonosis.
基金Supported by Science and Technology Support Program of Qinhuagndao City~~
文摘[Objective] The paper was to diagnose and treat hemorrhagic pneumonia of mink. [Method] The diseased minks bred by one raiser in Huangtian Village of Changli County in Qinhuangdao City were used as experimental materials. It was necropsied, and its tissues such as liver, kidney, spleen and lung were taken under aseptic condition, then inoculated into general nutrition agar and blood agar. The bacteria were isolated and purified, and the strains obtained were carried out animal inoculation test and drug sensitivity test. Finally, the relevant treatment and preven- tive measures were put forward. [Conclusion] The bacteria isolated were detected to be negative by Gram staining; it formed hemolysis ring in blood agar; the bacteria could ferment glucose and xylose, which could not ferment sucrose, lactose, maltose and esculin; it was positive in catalase and oxidase test, and negative in urease test and hydrogen sulfide test; so the strain was indentified to be Pseudomonas aerugi- nosa. Drug sensitivity test showed that the bacteria were highly sensitive to ciprofloxacin, which had tolerance to cefoxitin. [Conclusion] The study laid foundation for diagnosis and treatment of hemorrhagic pneumonia of mink.
基金Supported by the Health Department of Shandong Province,No,1999CA1CBA3
文摘AIM： To establish a new, reliable vomit model of minks METHODS： Adult male minks were randomly divided into 8 groups （n=6）： cisplatin （7.5 mg/kg） intraperitoneal injection （ip） group, copper sulfate （40 mg/kg） intragastric injection （ig） group, apomorphine （1.6 mg/kg） subcutaneous injection （sc） group, and 18 Gy whole-body X-irradiation group, ondansetron injection group （2 mg/kg ip） 30 min later followed by cisplatin （7.5 mg/kg） ip, normal saline （NS） ip injection control group, metoclopramide injection group （4 mg/kg ip） 30 rain later followed by apomorphine （1.6 mg/kg） sc, NS ig control group. The frequency of retching and vomiting was calculated. After behavioral experiment, distribution of 5-HT in the ileum was detected by immunohistologic method. RESULTS： Cisplatin, apomorphine, copper sulfate and X-irradiation administered to minks evoked a profound emetic response in the animals. However, retching and vomiting were significantly inhibited by pretreatment with ondansetron and metoclopramide in cisplatin and copper sulfate groups （P=0.018）. Immunohistologic result showed that 5-HT released from enterochromaffin cells （EC cells） was involved in vomiting mechanism. CONCLUSION： Mink vomit model has a great value in studying the vomiting mechanism and screening new antiemetic drugs.
基金supported by Special Fund for Public Welfare Technology Research of Agricultural Industry(200903014)
文摘A study was conducted to evaluate production performance of minks in growing-furring period with supplementing DL-Methinnine(Met)in low protein diet.Seventy healthy male minks were randomly divided into five groups of 14 minks each.The minks were fed in five kinds of experiment diets(HP,LP,LP+M1,LP+M2 and LP+M3).The dietary protein levels,expressed as percentage of dry matter(DM),were 32%(high protein,HP)and 24%(low protein,LP).LP was supple-mented with Met 0.4%(M1),0.8%(M2)and 1.2%(M3)DM.From mid of September to December 10,apparent digestibility of CP(crude pro-tein),N intake and urinary N excretion were decreased with declining dietary protein levels(p〈0.05)and N retained was the highest in treat-ment LP+M2.No significant difference was found in total serum protein(TP)and serum urea nitrogen(SUN)among all treatment groups(p〉0.05).Skin length of treatment HP and LP^M2 was higher than that of other groups(p〈0.05).Body length,skin weight,length of guard hair and under hair were not affected by different dietary protein levels(p〉0.05).The best performance could be observed in treatment LP+M2.In diet,24%(DM)protein level with 1.54%Met supplementing was enough for minks during growing-farring period.Dietary protein lowered from 32%to 24%with supplementing Met in diets would result in a37.9%decrease in urinary N excretion.Furthermore,addition of Met in diets for minks would be beneficial in terms of reducing feed expenses and lessening nitrogen emissions to the environment.
文摘Self-biting disease occurred in most farmed fur animals in the world. The mechanism and rapid detection method of this disease has not been reported. We applied bulked sergeant analysis （BSA） in combination with RAPD method to analyze a molecular genetic marker linked with self-biting trait in mink group. The molecular marker was converted into sequence-characterized amplified regions （SCAR） marker for rapid detection of this disease. A single RAPD marker A8 amplified a specific band of 263bp in self-biting minks, which was designated as SRA8-250, and non-specific band of 315bp in both self-biting and healthy minks. The sequences of the bands exhibited 75% and 88% similarity to Canis familiarizes major histocompatibility complex （MHC） class II region and Macaca mulatta MHC class I region, respectively. A SCAR marker SCAR-A8 was designed for the specific fragment SRA8-250 and validated in 30 self-biting minks and 30 healthy minks. Positive amplification of SCAR-A8 was detected in 24 self-biting minks and 12 healthy minks. χ2 test showed significant difference （p〈0.01） in the detection rate between the two groups. This indicated that SRA8-250 can be used as a positive marker to detect self-biting disease in minks. Furthermore, the finding that self-biting disease links with MHC genes has significant implications for the mechanism of the disease.
