Bilateral ocular anomalies in a South African fur seal (Arctocephalus pusillus pusillus)

A female South African fur seal (Arctocephalus pusillus pusillus) began having obvious clinical ophthalmologic problems by 8 weeks of age. The initial clinical sign was diffuse corneal edema, which progressed to bullae formation and ulcers; the underlying cause of corneal edema and bullous keratopathy was not identified antemortem. An ophthalmological evaluation was performed when the fur seal was approximately 6 months of age, but due to the diffuse corneal edema, intraocular structures could not be easily evaluated. An underlying infectious etiology was suspected; therefore, appropriate diagnostics were pursued, but did not identify a cause. Initial improvement was noted, but the fur seal then became blind and eventually became very painful. Due to decreased quality of life and aggressive behavior, the fur seal was euthanized. Histopathological diagnoses were persistent tunica vasculosa lentis and persistent hyperplastic primary vitreous with bilateral hypermature resorbed cataracts and retinal detachments with rosette formation.     

Geographical Distribution of African Mammals

This is a report of a marine predator (the white shark) being threatened by a member of the species on which it preys (a male Cape fur seal). Although these events may be rarely observed or occur infrequently, they may have important implications for the predator and its prey.We suggest that shark mobbing by adult male Cape fur seals is adaptive for the reduction of risk of predation by sharks. Mobbing of sharks is likely to alert conspecifics to the presence of a predator, and/or reduce the shark's hunting motivation near the mobbing site.     

Longitudinal study of northern fur seal (Callorhinus ursinus) hematology

Although the causes have not been specified yet, wild populations of northern fur seals (Callorhinus ursinus) have been decreasing, which is why conservation techniques such as captive breeding and health maintenance should be established. Hematological parameters can be used to maintain the health status of northern fur seals kept in captivity for artificial reproduction and public education. Year-round fluctuations of blood parameters have not been examined for northern fur seals due to the difficulties in obtaining serial blood samples from wild animals during the oceanic migration period from late autumn to spring. In this study, blood samples were collected from four captive northern fur seals and analyzed monthly for more than three years to clarify the seasonal fluctuation patterns in 14 hematological parameters. Many hematological parameters seemed to be seasonal patterns: summer–autumn and winter–spring; leukocyte-related parameters were higher in summer and autumn than in winter and spring; erythrocyte-related parameters were lower in summer and autumn than in winter and spring. Significant seasonal differences in nine of the 14 parameters were observed using a generalized linear mixed model (GLMM) analysis. These results have improved our understanding of the seasonal patterns of hematological characteristics in the northern fur seal and can contribute to the health care of protected or captive northern fur seals.     

Characterization of progressive keratitis in Otariids

Objective To characterize a form of progressive keratitis that occurs commonly in otariids. Materials and methods One hundred and thirteen captive otariids were evaluated by ophthalmologic examination and digital photography. Results Forty‐six females and 67 males were in the reference population, average age of 14 years. California sea lions predominated (n = 100); there were also six Steller sea lions, five brown fur seals, one Guadalupe fur seal and one northern fur seal. Three stages of progressive keratitis are described. Overall, 64.6% animals and 142 eyes from 113 animals (62.8%) were affected with one of three stages. The mildest form, Stage 1 keratitis, occurred in 78 of 226 eyes (34.5%); the intermediate Stage 2 keratitis occurred in 30 of 226 eyes (13.3%); and the most severe, Stage 3 keratitis, occurred in 34 of 226 eyes (15%). All but six animals had bilateral disease. Animals with Stage 1 keratitis were significantly younger than those in more advanced stages. Discussion ‘Otariid Keratitis’ occurs in all populations of eared seals evaluated. A large‐scale epidemiological study is ongoing to identify the risk factors that contribute to this disease. Exposure to chronic sunlight appears to be an important risk factor as shade diminishes clinical signs; animals kept out of sunlight the majority of the time have less severe clinical signs. Age may be important since exposure accumulates with aging. Progression of the disease is also associated with secondary opportunistic bacterial and fungal infections. The surface immune system may be imbalanced contributing to these infections and progression.     

Tuberculosis in wild seals and characterisation of the seal bacillus

SUMMARY Tuberculosis was diagnosed in 3 otariid seals found dead on beaches at 3 locations on the south coast of Western Australian between May 1990 and March 1991. This confirms that tuberculosis is present in the 2 native seals (Neophoca cinerea and Arctocephalus forsteri) in Western Australian waters. Mycobacterium sp isolated from the lungs of 2 of the seals were studied to determine the similarity of the strains to each other, to the strains isolated during 1986 from Australian sea lions and New Zealand fur seals kept in captivity at a marine park near Perth, Western Australia, and to a strain isolated in 1988 from a seal trainer who worked with the infected captive seals for 3 years. After restriction endonuclease analysis (REA) with the endonucleases Bst Ell, Bcl I and Pvu II, one of the wild seal strains appeared to have identical DNA fragment patterns to the strains from the captive seals and the seal trainer. The other wild seal isolate had identical REA profiles using Bst EII and Bcl I, but a minor difference was detected using Pvu II. Differences in these isolates were more clearly seen in restriction fragment length polymorphisms after hybridisation with two DNA probes. The secretory protein MPB70, present in M bovis, was not detected in wild seal isolates using sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blotting techniques. Analysis of protein and DNA fragment profiles indicated that seal tuberculosis isolates form a unique cluster within the M tuberculosis complex.     

Restoration of fractured canines in ferrets after one-step root canal treatment

This article describes a one-step root canal treatment and restoration of canine teeth in ferrets. Standard brass posts were used for the reconstruction of the teeth. The procedures were performed by dentists according to all rules and procedures used in root canal treatment in humans. The teeth were immediately restored anatomically. The procedures were successfully performed in four ferrets aged between 6 and 20 months of age, in three upper and one lower canines.     

Age estimation in the harbour seal (Phoca vitulina) based on the closure of skull sutures and synchondroses

Age estimation of individuals is an important tool for the management of marine mammals and is mostly done by microscopic analysis of growth layer groups (GLGs) in teeth (cementum and dentin) and bone. The present study evaluated the use of sutural and synchondrosal closure in the skull of the harbour seal (Phoca vitulina) as a potential non-destructive alternative for age estimation. For that, we scored the ectocranial closure of 12 selected sutures and synchondroses in a sample of 303 Eastern Atlantic harbour seals (P. v. vitulina; 138 males, 165 females), for which data on age at death were available, based on determined gross-morphological criteria in individuals younger than 1 year and cement layer analysis in canines in older individuals. A strong positive relationship between the sum of closure level scores (SCS) and age (males: r = 0.8797, females: r = 0.8825) was recorded, which was stronger than that for the relationship between age and condylobasal length (CBL, males: r = 0.7085, females: 0.7086) (all p-values <0.0001). In adult individuals (≥5 years), CBL was higher in males than females (p < 0.0001), while SCS did not significantly differ between the two sexes (p = 0.148). Our findings show that the analysis of sutural/synchondrosal closure is a valid alternative for age estimation in harbour seals, thereby confirming results of previous studies on other pinniped species.     

Vagrant Subantarctic fur seal on the coast of Tanzania

An immature Subantarctic fur seal was sighted on Unguja Island, Zanzibar, Tanzania, in 2008. This is the most northerly record of a vagrant of this species. The nearest breeding colony is on the Prince Edward Islands, 4500 km distant. While it is likely that this is the natal site of the vagrant due to its proximity and population size, the actual location of origin is unknown. This is the second fur seal sighted in this area. A fur seal of unknown species was sighted on Pemba Island, 30 km north of the Unguja Island, in 2002. While the species of the latter animal could not be determined, it is likely also a Subantarctic fur seal.     

Preliminary investigation of a possible lung worm (Parafilaroides decorus), fish (Girella nigricans), and marine mammal (Callorhinus ursinus) cycle for San Miguel sea lion virus type 5

Colostrum-deprived neonatal Northern fur seal pups (Callorhinus ursinus) were exposed to San Miguel sea lion virus type 5 (SMSV-5) by feeding them fish (Girella nigricans) infected with virus or fish infected with both the sea lion lung worm larvae (Parafilaroides decorus) and virus. Virus infection was demonstrated in 8 of 9 pups, and 1 of these developed a vesicular lesion on the flipper. In this sequence, P decorus larvae exposed to SMSV-5 were fed to G nigricans held at 15 C in a salt water aquarium; 32 days later, these fish were killed, then fed to the fur seal pups. The vesicle developed 22 days subsequent to this and SMSV-5 was reisolated from the lesion. The SMSV-5 was shown to persist for at least 23 days in infected neonatal fur seals. Attempts to establish P decorus infection in Northern fur seal pups were apparently unsuccessful.     

White shark (Carcharodon carcharias)-inflicted bite wounds observed on Cape fur seals (Arctocephalus pusillus pusillus) at Black Rocks,Algoa Bay,South Africa

This paper presents the first quantitative study on the seasonal occurrence and body location of white shark (Carcharodon carcharias)-inflicted injuries on Cape fur seals (Arctocephalus pusillus pusillus) at Black Rocks, in Algoa Bay. Between January 2010 and October 2011, 22 boat trips were made to Black Rocks to chum for white sharks. On 19 of the trips a series of overlapping photographs were taken of the northern side of Black Rocks and the percentage of seals, which exhibited fresh white shark bite wounds recorded. A total of 53 sharks and 28 fresh shark-inflicted injuries were recorded on seals over the course of the study period. The maximum number of sharks sighted per hour (1.2) was in July and the highest percentage of shark bitten seals in November (0.6%). There was no significant relationship between the monthly sighting rate of sharks and the percentage of shark bitten seals (P = 0.40). The percentage of shark-inflicted injuries observed on seals increased with seal size. Most injuries were observed in the forebody (37.5%) and lower body regions (37.5%). Very few injuries (6.3%) were observed in the head and neck region. The low number of bite-inflicted injuries observed suggests that white sharks attack seals infrequently at Black Rocks.     

Vagrant Subantarctic fur seal in the Mayumba National Park,Gabon

A vagrant adult male Subantarctic fur seal Arctocephalus tropicalis was seen and photographed on the beach in Mayumba National Park in the Gabonese Republic. This is the northern most sighting on record for the species. The likely source of the vagrant is the population at Gough Island, South Atlantic.     

Clinical dental examinations of 357 donkeys in the UK. Part 1: Prevalence of dental disorders

Reasons for performing study: Dental disorders have a high prevalence in older donkeys and horses, but the nature and pathogenesis of many of these disorders have yet to be established. Objectives: The identification and determination of the prevalence of important dental disorders in different age groups in a large single population of donkeys, to establish a better understanding of the nature and pathogenesis of these disorders. Methods: A prospective cross‐sectional study was performed on the donkey population at The Donkey Sanctuary with detailed oral examinations of 357 donkeys within 7 different age groups (age range 2–53 years) recorded. Results: The prevalence of dental disease in all donkeys was 73%, increasing in prevalence from 28% in the youngest to 98% in the oldest age group. There was an increase in prevalence of commonly recognised dental disorders with increasing age, such as: diastemata (3.8% in youngest to 86% in oldest group); missing teeth (0–56%); overgrown teeth (15–86%); worn teeth (8–84%); displaced teeth (0–38%); and periodontal disease (0–28%). Conclusions: There was a significant increase in the prevalence of dental disorders with increasing age with the largest significant increase for most dental disorders occurring in the 15–20 year age group. Potential significance: Most dental disorders significantly increase in prevalence in the 15–20 year age group and, therefore, prophylactic geriatric dental treatment in donkeys should be commenced from age 15 years.     

Serological survey of pre-weaned New Zealand fur seals (Arctocephalus forsteri) for brucellosis and leptospirosis

AIM: To conduct a longitudinal serological survey for evidence of Brucella spp and Leptospira spp infection of pre-weaned New Zealand fur seals in a colony on the Otago Peninsula.

METHODS: Seal pups were repeatedly captured on a monthly basis from February through to July 2001. Pups were tagged at first capture and a blood sample was taken at each capture event. A total of 163 sera were collected from 118 seal pups. Where sufficient volume was collected, the sera were tested for leptospirosis using the microscopic agglutination test (MAT), and for brucellosis using the competitive enzyme-linked immunosorbent assay (ELISA) for Brucella abortus.

RESULTS: None of 128 sera from 101 seals tested positive to the ELISA for B. abortus. All tests for Leptospira interrogans serovars Grippotyphosa, Copenhageni, Bratislava and Leptospira borgpetersenii serovar Ballum were negative at a cut-off of <1/100 dilution. Positive or suspicious titres were found to L. interrogans serovars Canicola and Pomona and L. borgpetersenii serovar Hardjo. The highest titres (12,800) were found to serovar Pomona. The titre to serovar Pomona in one seal rose from <1/50 in March to 12,800 in April and was <1/50 when re-sampled in July. The titre to serovar Pomona in another seal dropped from 12,800 in May to <1/50 in June. These seals also had titres to serovar Hardjo, which rose or fell in the same manner. All suspicious or positive titres occurred in late April and early May, when the pups were approximately 4–5 months old. In June and July, all seals tested were negative.

CONCLUSIONS: There was no serological evidence of Brucella infection in the pre-weaned fur seals at the colony. Positive titres to serovars Pomona, Hardjo, or Canicola suggest that a Leptospira species was present at the colony, however isolation or visualisation of the organism is required to confirm this. Care should be exercised when handling New Zealand fur seals to prevent human infection or inadvertent transfer of leptospirosis to another marine mammal species.     

Age determination of eland Taurotragus oryx (Pallas, 1766) in the Natal Highveld

Techniques for the age determination of highveld eland in Natal were investigated. Tooth eruption and replacement sequence, and growth in horn length, were suitable criteria for the age determination of young eland with deciduous dentition. The most accurate technique for the age determination of post mortem adult eland was based on counts of cementum annuli from molar teeth. Animals without distinctive cementum annuli may be assigned ages from measurements of M₃ crown height. The ages of live restrained eland could be derived from measurements of I₁ occlusal width or I₁, crown height. Horn morphology was adequate for age and sex classification of free-ranging eland up to adult status.     

Feeding Habits of the Giant Clingfish Chorisochismus Dentex (Pisces: Gobiesocidae)

The feeding habits of the giant clingfish Chorisochismus dentex in the eastern Cape Province, South Africa, are described. Juveniles share a diet of small crustaceans with numerous other fish species but adults feed on sea urchins as well as on a rarely used resource — limpets (Patellidae) which are firmly attached to rocks in the intertidal zone. The limpets are removed by levering with the large upper incisiform teeth. Undigested shells are eliminated whole encased in mucous capsules.     

Current prevalence of adult Uncinaria spp. in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, California, with notes on the biology of these hookworms

A prevalence survey for hookworms (Uncinaria spp.) was done in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, CA, in 2000. Intestines of dead pups were examined for adult hookworms in July. These parasites were found in 95% of 20 fur seal pups and 100% of 31 sea lion pups. The number of hookworms varied from 4 to 2142 (mean = 760) in fur seal pups and from 20 to 2634 (mean = 612) in sea lion pups. A direct relationship was evident between body condition and number of hookworms in the pups; that is, pups in poor condition had fewer hookworms than those in good condition. There was a decline in the number of hookworms in sea lion pups in 2000 compared to collections in 1996. Eggs of Uncinaria spp. were found in rectal feces (collected in late September and early October) of none of 35 (0%) live fur seal pups and 41 of 48 (85%) live sea lion pups. Packed cell volume values, determined for most of the same live pups, were essentially normal for C. ursinus but were much lower than normal for most Z. californianus. Hookworm larvae were not found in blubber of fur seal and sea lion pups or in rookery sand in July. Rookery sand, positive for live hookworm larvae when put in a refrigerator, was negative at removal 2.5 years later. The average number of eggs in utero of female hookworms was 285 for three specimens from a fur seal pup and 281 from three specimens from a sea lion pup. One hookworm larva was recovered from milk stripped from the teats of a stranded Z. californianus female at The Marine Mammal Center, Sausalito, CA.     

Prevalence of Coxiella burnetii and Brucella spp. in tissues from subsistence harvested northern fur seals (Callorhinus ursinus) of St. Paul Island,Alaska

Background

The northern fur seal (Callorhinus ursinus) is an important cultural and nutritional resource for the Aleut community on St. Paul Island Alaska. In recent years, an increasing number of zoonotic pathogens have been identified in the population, but the public health significance of these findings is unknown. To determine the prevalence of Coxiella burnetii and Brucella spp. in northern fur seal tissues, eight tissue types from 50 subsistence-harvested fur seals were tested for bacterial DNA by real-time polymerase chain reaction.

Findings

Of the 400 samples tested, only a single splenic sample was positive for Brucella spp. and the cycle threshold (ct) value was extremely high suggesting a low concentration of DNA within the tissue. C. burnetii DNA was not detected.

Conclusions

Findings suggest that the risk of humans contracting brucellosis or Q fever from the consumption of harvested northern fur seals is low.     

Energy Metabolism of the Cattle Egret

Ages were estimated for the tropical sparid, Acanthopagrus berda, caught in northern KwaZulu-Natal estuaries. Whole otoliths were used in the age determination. Age estimates were validated by marginal increment analysis and oxytetracycline labelling, which indicated that opaque deposition occurs primarily from September to November each year. The reproducibility of age estimates was described by a coefficient of variation of 10%. The von Bertalanffy growth curve was found to best describe the growth of A. berda. The parameters of the von Bertalanffy growth curve indicated that A. berda in northern KwaZulu-Natal is a slowgrowing species, capable of reaching at least 16 years of age. Longevity of the species, coupled with sex change, late maturation and estuarine dependency, give cause for concern for the continued sustainable utilization of this species.     

A record of the sub-Antarctic fur seal Arctocephalus tropicalis in Angola

Two individuals of the sub-Antarctic fur seal, Arctocephalus tropicalis, one of which was photographed, were seen on the beach 1 km south of the mouth of the Kwanza River, Angola, on 2 October 1983. This record represents a northerly extension by some 2 700 km of the previously recorded range. The nearest breeding colony is at Tristan da Cunha about 4 000 km south-west of this sighting.     

毛皮动物育种软件应用现状与展望

动物育种软件的应用,告别了传统的表型选种时代,对育种准确性的提高起到了至关重要的作用。我国在毛皮动物育种软件的研发与应用上还不成熟,而软件在动物育种中的应用是当前乃至未来规模化养殖的大势所趋。本文针对目前育种软件在畜禽和毛皮动物中的应用现状,从育种资料管理、遗传评估系统、计算机模拟研究、育种专家系统、网络信息传递与共享5个方面进行了相关论述,并在归纳、总结畜禽育种软件研究成果、先进经验的基础上,结合毛皮动物的自身特点,探讨了在毛皮动物中应用育种软件的必要性和可行性,以期能为今后毛皮动物育种软件的应用提供参考。