Kidney structure of a euryhaline mammal,the Cape clawless otter (Aonyx capensis)

The Cape clawless otter (Aonyx capensis) is one of the few species of mammals that occur in both freshwater and marine habitats, and it therefore must be able to tolerate the high rates of water flux typical of aquatic animals as well as the desiccating effects of seawater. The clawless otter has paired, discrete multirenculate kidneys (total mass = 172 g) comprised of both unipapillary and bipapillary renculi weighing an average of 2.6 and 3.2 g, respectively, The average thickness of the cortex is 2.3 mm, and thicknesses of the outer and inner medulla are 2.4 and 6.4 mm, respectively. These measurements and the overall structure of the kidney of the Cape clawless otter are intermediate between those of freshwater and marine mammals.     

Monitoring the effects of land transformation on African clawless otters (Aonyx capensis) using fecal glucocorticoid metabolite concentrations as a measure of stress

In a time of increasing environmental change caused by anthropogenic disturbance, there is a greater need to understand animal adaptations to manmade environments. In this regard, the measurement of stress‐related endocrine markers provides a useful tool to examine the impact of environmental challenges and the physiological consequences for wildlife occupying such space. The aims of the present study were to validate fecal glucocorticoid metabolite (fGCM) concentrations as a measure of stress using samples from a male African clawless otter (Aonyx capensis; n = 1) and to compare fGCM concentrations of otters occurring in a transformed and in 2 natural areas in South Africa. From the 5 different enzyme‐immunoassays (EIA) tested, a cortisol and oxoetiocholanolone (measuring 11,17 dioxoandrostanes) EIA revealed the highest response (74% and 48% increase, respectively) 30 and 24 hours after a stress event (translocation of a captive individual as part of its rehabilitation prior to release), respectively. For both EIAs, fGCM concentrations were comparable for samples collected up to 3 h post‐defecation. Using the cortisol EIA for subsequent analyses, fGCM concentrations of animals from the transformed area (n = 20; mean [± SD]: 0.468 [± 0.539] µg/g dry weight [DW]) were significantly higher (P = 0.013) than those from otters in the natural areas (n = 17; 0.242 [± 0.226] µg/g DW). These preliminary results suggest that African clawless otters may have increased adrenocortical activity that could be due to conditions linked to living in a transformed environment.     

Reproduction in the Cape horseshoe bat (Rhinolophus capensis) from South Africa

Structure of the reproductive organs and the processes of spermatogenesis and follicular development are described and are· similar to those described for other members of the genus Rhinolophus. The reproductive cycle of the Cape horseshoe bat is characterized by spermatogenesis between October and May (spring to autumn) with sperm released to the cauda epididymis in April and May. At this time the females are in oestrus or submaximal oestrus but copulation and ovulation are delayed until August and September (the end of winter hibernation). Between May and September spermatozoa are stored in the cauda epididymis where they show no positive association with the epididymal epithelium. Parturition occurs in November and December after a three to four month gestation.     

Prevalence of Helminth Infections in the Cape Hare (Lepus capensis) in Iran

Veterinary Research Communications -     

Evaluation of urinary and serum metabolites in Asian small-clawed otters (Aonyx cinerea) with calcium oxalate urolithiasis.

Baseline renal function data was collected during 24-hr periods of feeding and fasting from three male and three female adult Asian small-clawed otters (Aonyx cinerea) with calcium oxalate urolithiasis. Urine was analyzed for calcium, phosphorus, and oxalate, and urinalyses were performed. There was no evidence of glucosuria, which has been previously reported in Asian small-clawed otters with urolithiasis. Urinary oxalate levels were quite high when compared with those of dogs and humans without uroliths, and the ratio of urinary oxalate to calcium was close to 1:1 during periods of food consumption. There was no significant difference in urinary oxalate excretion between the fed and fasting states. Urinary calcium excretion was five times greater during feeding than during fasting. Calcium levels were higher in the otters than those reported for dogs without uroliths but were similar to those for normal humans. Water consumption and urine production were significantly higher during periods of food consumption. Serum chemistry analyses and electrolyte levels were also determined. There was no evidence of hypercalcemia. Fractional clearance of calcium and phosphorus and endogenous creatinine clearance were significantly higher during food consumption than during fasting. Parathyroid hormone levels were similar to those reported for dogs and cats. Serum 25-hydroxy-vitamin D was slightly lower in the otters than in dogs.     

The new French 2010 Rabbit Hemorrhagic Disease Virus causes an RHD-like disease in the Sardinian Cape hare (Lepus capensis mediterraneus)

Lagovirus is an emerging genus of Caliciviridae, which includes the Rabbit Hemorrhagic Disease Virus (RHDV) of rabbits and the European brown hare syndrome virus (EBHSV) of hares that cause lethal hepatitis. In 2010, a new RHDV related virus (RHDV2) with a unique genetic and antigenic profile and lower virulence was identified in France in rabbits. Here we report the identification of RHDV2 as the cause in Sardinia of several outbreaks of acute hepatitis in rabbits and Cape hare (Lepus capensis mediterraneus). This is the first account of a lagovirus that causes fatal hepatitis in both rabbits and hares.     

Seasonal abundance,growth and production of Palaemon pacificus (Stimpson) in eastern Cape tidal pools

The shrimp Palaemon pacificus was sampled monthly from six tidal pools for two years. The shrimp populations varied seasonally with peak numbers and biomass found in summer (December to March) following a major influx of juveniles in November. These recruits were composed of discrete modal groups (bimodal) which spread and became less obvious by April (polymodal). Females had a greater mean size range than males. The sex ratio varied temporally and overall male:female ratios varied from 1:1,66 to 1:2,96. Average shrimp total length was significantly correlated to the average and maximum pool depth and to log pool volume while the average number of cohorts per year was found to be negatively correlated to these parameters. In smaller pools the shrimp disappeared above 20-30 mm but remained up to reproductive age in the deeper pools. Average residence time was positively correlated to pool depth, but not to log volume. Mean summer growth rates were almost double those in winter and were combined in the von Bertalanffy growth equation L, = 64,51 (1-e^{-0,08902(t-0,1001})). P. pacificus reaches first maturity from egg at six months for males and 12 months 2 for females. Mean annual production varied between pools from 0,22 to 2,0 g m ^-2 and biomass from 0,06 to 0,5 gm^-2. The highest P/B ratio of 4,24 was obtained from the smallest pool which had a low biomass but high productivity and shrimp turnover.     

Seasonal habitat requirements of Lemon Dove (Aplopelia larvata) in coastal forest: camera-trap surveys of a reclusive species

The modification of natural habitats requires behavioural plasticity, which may be challenging for ‘specialist’ species. Quantifying habitat requirements and behavioural responses of specialists to landscape transformation is thus a priority for baseline data to inform conservation practices. Using camera-trap surveys of the forest-dependent Lemon Dove Aplopelia larvata in conjunction with detailed microhabitat-scale covariates, we assessed habitat use during two periods in the year: autumn–winter and spring–summer (which largely encompassed peak breeding). We used occupancy modelling of forest-structural covariates to produce models of the probability of occupancy and detection of Lemon Doves in patches of the Indian Ocean Coastal Belt Forest of South Africa. The average occupancy and detection probability as indicated by the top-performing models was 0.39 ± 0.08 and 0.26 ± 0.05, respectively, during autumn–winter, and 0.37 ± 0.08 and 0.25 ± 0.04, respectively, during spring–summer. Although occupancy and probability of detection remained relatively constant between seasons, there was seasonal variation in the influence of individual covariates for both measures. The overall trend of positive influences on Lemon Dove occupancy was that of complex and diverse habitat structures and high plant species richness. The specific covariates that influenced occupancy positively during spring–summer may reflect the ecological requirements for nestling provisioning for both dietary needs and an avoidance of potential disturbance. Thus, while Lemon Doves may be less habitat-specific during autumn–winter, conservation management plans for safeguarding the breeding success of the species are advised to ensure adequate protection of large forest patches with complex and diverse interior structures and minimal disturbance.     

New canine parvovirus 2a infection in an imported Asian small-clawed otter (Aonyx cinereus) in Japan

Post-import from the Republic of Indonesia to Japan in 2017, two juvenile, captive bred Asian small-clawed otters (Aonyx cinereus) exhibited gastrointestinal symptoms, including vomiting, diarrhea, and hematemesis, and died. One of them was examined postmortem. Microscopically, the small intestinal mucosa was necrotic with crypts lined by regenerating large epithelial cells. A gastric cardiac mucosal ulcerative lesion containing fungal yeasts and pseudohyphae morphologically indicated Candida spp. The lymph nodes exhibited marked lymphoid depletion. Canine parvovirus 2 (CPV-2) was isolated from an oral swab, and virus protein 2 (VP2) gene sequencing revealed new CPV-2a. To our knowledge, this is the first new CPV-2a infection report in Asian small-clawed otters. This infection should be considered in gastrointestinal symptom-related cases in this species.     

Seasonal effects on digging activity and burrow architecture in the Cape dune mole-rat,Bathyergus suillus (Rodentia: Bathyergidae)

Most polygynous male mammals exhibit little or no parental care or involvement raising young. Instead, they invest indirectly in their own morphological and physiological attributes which enhance their chance of reproduction. Such secondary morphological sex traits may contribute to differences in the burrow architecture of fossorial mammals, such as the Cape dune mole-rat, Bathyergus suillus. Indeed, little is known about the seasonal changes in burrow architecture or differences in burrow configuration may differ between the sexes of subterranean African mole-rats (Bathyergidae). We excavated burrow systems of male and female B. suillus during the summer and the winter to investigate whether male burrow architecture reflected putative mate-seeking behaviour. We consider burrow geometry in response to mating strategies. Male burrow systems explored the environment more efficiently than females. This is presumably because of the increase in associated energetic costs of being a large male. Males produce more mounds indicating territorial behaviour even when it is energetically costly to dispose of soil onto the surface when the soil is less friable during the summer. Overall tunnel dimensions did not differ between the sexes. It appears that a change in season does not affect the geometry of the burrow system or tunnel dimensions in a climatically buffered environment.     

Isolation of a Mycobacterium microti-like organism from a rock hyrax (Procavia capensis) in a Canadian zoo

A Mycobacterium tuberculosis complex organism was isolated from a zoo resident rock hyrax (Procavia capensis) imported into Canada from South Africa. The strain was identified biochemically as Mycobacterium microti. The spoligotype pattern obtained for this isolate was found to be rare. This represents the first report of isolation and spoligotyping of M. microti in North America.     

Song variation of a native songbird in a modified habitat by invasive plant

Habitat structure has been considered as an important factor affecting the acoustic evolution of birds, and bird songs are increasingly affected by artificial environmental variation. Invasive plants sometimes can dramatically alter native habitats, but the song variation of native songbirds migrating into invaded habitats has received little attention. The invasion of smooth cordgrass Spartina alterniflora in the coastal wetlands of eastern China has drastically altered the vegetation structure and some small passerines have begun to use invaded habitats to breed. In this study, we compared the song type prevalence and the song characteristics of male plain prinia Prinia inornata to identify differences in vocal behavior between native and invaded habitats. We also tested for differences in vocal behavior in relation to singing perch and wind speed variation between different habitats. The results indicated that males of plain prinia in invaded habitats sang shorter songs than those in native habitats and had a lower song diversity. The homogeneous vegetation structure and higher wind speed in invaded habitats likely leads to males changing the traditional perched singing style. The song variation may be related to the founder effect, the alteration of vegetation structure and microclimate in invaded habitats. This finding highlights the need for better understanding the behavioral evolution of native species in the process of adapting to the invaded habitat. In the future, experimental manipulation is needed to ascertain how the invasive plant drove these vocal behavior changes of native songbirds.     

Observer variation in the histological diagnosis of plasmacytoid leukemia (marine anemia).

The reliability of past histological criteria for the diagnosis of plasmacytoid leukemia was investigated by studying observer variation in the diagnosis of the disease. Participants blindly evaluated a series of histological samples and classified them as positive, negative or questionable cases of the disease. Intra- and interpathologist agreement were used to assess reliability and were determined by calculating the observed agreement in diagnosis and the kappa statistic. There was poor overall agreement for the classification of sample cases. Questionable cases were most frequently misclassified but marked disagreement also existed for positive and negative samples. Access to historical information prior to histological examination influenced agreement. The results show that previously described histological criteria alone were insufficient for establishing the diagnosis of plasmacytoid leukemia.     

Seasonal variation in blood biochemistry of long-term captive Mediterranean tortoises (Testudo graeca and T hermanni)

Reference values for five blood chemistry parameters in 18 Mediterranean tortoises of two species, Testudo graeca and T hermanni, were determined on up to 10 occasions during the year. Statistically significant seasonal variations were demonstrated in blood urea and blood glucose. Seasonal variations were demonstrated in blood urea and blood glucose. Seasonal variations in total plasma proteins, lipids and cholesterol, however, were limited to gravid females. The study also suggested that three energy sources were available to the tortoise during hibernation, lipids stored in the fat body, endogenous protein degradation and glucose derived from hepatic glycogen.     

Trapping and handling of North American river otters (Lontra canadensis) in a managed marsh.

North American river otters (Lontra canadensis) were trapped in a managed marsh in northern California between July and November of 1998. Five trap types using several set configurations were utilized in this study. Otters were successfully captured with minimal injury and a relatively high trap rate (1 capture per 48 trap nights), with the use of No. 1.5 and No. 1.75 double-coil spring traps, and No. 11 double long spring traps on short chains in blind land sets, or in bank sets on one-way cables leading to land-buried stakes. Only 3 of 14 captures incurred more than minimal injuries, and all 3 of these were exacerbated by complications from traps attached to long chains. Otters were captured at any time of day, although activity appeared lowered between 0900 and 1900 hours. Otters were anesthetized for handling. Monitoring results and anesthetic complications are reported for 14 captures. Ketamine (15 mg/kg) and midazolam (0.5 mg/kg) provided a wide margin of safety, rapid induction at low injection volume, good anesthetic quality, handling time of about 30 min, and few complications. White blood cell counts were taken and appeared high relative to reported values in other studies. This trend is likely attributable to blood draws immediately after the animal had been held in a trap for several hours, in contrast to most other studies, in which blood was drawn days to weeks after being held in captivity.     

A model explaining patterns of geographic character variation in Cordyius cordylus (Reptilia; Cordylidae) in the south-western Cape,South Africa

A model is proposed for the evolution of three morphotypes of the girdled lizard Cordylus cordylus (Linnaeus) in the south-western Cape. The available data are interpreted as indicating that a vicariant splitting of a warm-adapted ancestral population during the last glacial period occurred. Differential evolution of the two daughter populations in response to different environmental pressures resulted. One of the daughter populations remaining in the coastal lowlands to the west of the Cape Fold Mountains, became cold-adapted, an event which was followed by a rapid range expansion. The other daughter population to the south and east of the Cape Fold Mountains apparently experienced less severe climatic conditions, maintained a larger population size, and for these reasons remained warm-adapted. During the subsequent warmer, interglacial period the now cold-adapted daughter population was again fragmented into two populations. Of these, one is presently found along the south-western coast and the other along the higher peaks of the western section of the Cape Fold Mountains. On the other hand the amelioration of the climate during the interglacial allowed the warm-adapted daughter population to the south and east to expand its range, eventually penetrating into the areas formerly occupied by the cold-adapted populations. Subsequently zones of secondary contact were established. In the area under discussion similar patterns of contraction and expansion can be observed in other closely related species. Our data support the turnover-pulse hypothesis of Vrba (1985)     

Description of a new species of Afroedura (Loveridge) (Reptilia: Gekkonidae) from the south-western Cape

A new gekkonid species, Afroedura hawequensis, is described from the south-western Cape (South Africa). The three species groups recognized in the genus are discussed.     

Seasonal variation in nuclear DNA integrity of frozen-thawed spermatozoa from Thai AI swamp buffaloes (Bubalus bubalis)

In this study, we investigated the susceptibility of frozen-thawed swamp buffalo sperm nuclear DNA to undergo controlled acid-induced denaturation in situ, as analysed by flow cytometry, and aimed to correlate the results with sperm head morphology over three seasons in tropical Thailand. Artificial insemination (AI) doses (n = 218) from 18 AI buffalo sires, prepared between 1980 and 1989 and 2003 and 2005, were tested and compared among three seasons, the rainy season, July-October; winter, November-February; and summer, March-June. The overall mean of DNA fragmentation index (DFI) (+/- SD) was 1.84 +/- 1.68%, range from 0.19 to 7.92%, with 0.221 +/- 0.021 of the x-DFI ranging from 0.190 to 0.350 and 0.023 +/- 0.009 of the SD-DFI ranging from 0.010 to 0.070. The DFI was consistently low (range 1.40 +/- 0.21% to 2.16 +/- 0.21%; LSM +/- SEM), with x-DFI ranging from 0.216 +/- 0.003 to 0.225 +/- 0.003 and SD-DFI ranging from 0.022 +/- 0.001 to 0.024 +/- 0.001 across the seasons. The DFI was low enough to be related to high fertility potential. However, DFI values varied statistically among seasons, being lower in the rainy season (1.40 +/- 0.21%, P < 0.05) than in winter (2.16 +/- 0.21%) or summer (2.00 +/- 0.20%), and were also affected by the year of semen collection and processing (P < 0.001). The proportion of morphologically abnormal sperm head shapes was low, with no significant differences between seasons. However, DFI was significantly related to the proportion of loose abnormal sperm heads (r = 0.27, P < 0.01). In conclusion, frozen-thawed swamp buffalo sperm chromatin integrity is not seriously damaged by cryopreservation or affected by the seasonal variations in temperature and humidity seen in tropical Thailand.