Ovarian folliculogenesis in collared peccary, Pecari tajacu (Artiodactyla: Tayassuidae)

The sustainability and production of collared peccary (Pecari tajacu) has been studied in the last few years; however, further information on its reproduction is necessary for breeding systems success. Understanding folliculogenesis aspects will contribute to effective reproductive biotechniques, which are useful in the preservation and production of wildlife. The aim of this study was-to evaluate the ovarian folliculogenesis in collared peccary. Ovaries from six adult females of collared peccary were obtained through ovariectomy and analyzed. These were fixed in aqueous Bouin's solution and sectioned into 7 microm slices, stained with hematoxilin-eosin and analyzed by light microscopy. The number of pre-antral and antral follicles per ovary was estimated using the Fractionator Method. The follicles, oocytes and oocyte nuclei were measured using an ocular micrometer. Results showed that the length, width, thickness, weight, and the gross anatomy of the right and left ovaries were not significantly different. However, the mean number of corpora lutea was different between the phases of the estrous cycle (p<0.05), with the highest mean in the luteal phase. Primordial follicles were found in the cortex; the oocytes were enveloped by a single layer of flattened follicular cells. In the primary follicles, proliferation of the follicular cells gave rise to cuboidal cells (granulosa cells). The secondary follicle was characterized by two or more concentric layers of cuboidal cells (granulosa), beginning of antrum formation, and the presence of pellucid zone and theca cells. Antral follicles were characterized by a central cavity (antrum), the presence of cumulus oophorus and theca layers (interna and externa). In the right ovary, the values of the primordial and primary follicles were similar, but significantly different from the secondary ones (p<0.05). In the left ovary, significant differences were observed between all follicles in the follicular phase (p<0.05); the mean number of primordial and primary follicles was similar in the luteal phase. The mean number of pre-antral follicles and antral follicles in the follicular phase was higher in the left ovary (p<0.05). The mean number of antral follicles in the luteal phase was similar in both ovaries. We also found significant differences in mean diameter of preantral follicles, oocyte, granulosa layer and oocyte nucleus during the estrous cycle. In the antral follicles a significant difference was observed only in follicular diameter (p<0.05). The predominance of active primordial and primary follicles was found in both phases; otherwise the secondary follicles and antral follicles showed a high degree of degeneration. The results obtained in the present work will strengthen the development of biotechnology programs to improve the productive potential and conservation of the collared peccary.     

Amblyomma vikirri n. sp. (Acari: Ixodida: Ixodidae), a parasite of the gidgee skinkEgernia stokesii (Reptilia: Scincidae) from South Australia

All active stages of the tickAmblyomma vikirri n. sp. (Acari: Ixodidae) are described from the gidgee skinkEgernia stokesii, a widely distributed lizard in South Australia, western New South Wales, western Queensland, Northern Territory and Western Australia. Thus far, the tick has been collected from this host only in the Flinders and Gawler Ranges of South Australia, plus a single record from Mt Dare in the far north of South Australia. Adults attach primarily on the tail and hind-back ofE. stokesii, while the larvae and nymphs prefer the ears and between the toes.     

Life cycle and host specificity of Amblyomma triste (Acari: Ixodidae) under laboratory conditions

We report biological data of two generations of Amblyomma triste in laboratory and compared the suitability of different host species. Infestations by larval and nymphal stages were performed on guinea pigs (Cavia porcellus), chickens (Gallus gallus), rats (Rattus norvegicus), rabbits (Oryctolagus cuniculus), wild mice (Calomys callosus), dogs (Canis familiaris) and capybaras (Hydrochaeris hydrochaeris). Infestations by adult ticks were performed on dogs, capybaras and rabbits. Tick developmental periods were observed in an incubator at 27 °C and RH 90%. Guinea pigs were the most suitable hosts for larvae and nymphs, followed by chickens. The remaining host species were less suitable for immature ticks as fewer engorged ticks were recovered from them. Mean larval feeding periods varied from 3.8 to 4.7 d between different host species. Mean larval premolt periods ranged from 8.9 to 10.4 d. Nymphal mean feeding periods varied from 4.2 to 6.2 d for ticks fed on different host species. Premolt period of male nymphs (mean: 15.4 d) was significantly longer than that of female nymphs (14.7 d). Female nymphs were significantly heavier than male nymphs. The overall sex ratio of the adult ticks emerged from nymphs was 0.9:1 (M:F). Capybaras were the most suitable host for the tick adult stage as significantly more engorged females were recovered from them and these females were significantly heavier than those recovered from dogs or rabbits. The life cycle of A. triste in laboratory could be completed in an average period of 155 d. The potential role of guinea pigs, birds and capybaras, as hosts for A. triste in nature, is discussed. This revised version was published online in July 2006 with corrections to the Cover Date.     

White-lipped peccary (Tayassu pecari,Artiodactyla: Tayassuidae) diet and fruit availability in a Costa Rican rain forest

We studied fruit availability, diet and habitat use by white-lipped peccary (Tayassu pecari) in Corcovado National Park, southwest Costa Rica, from July 1996 to April 1997. The results show that the availability of important fruits for the white-lipped peccary differs between habitats and climatic seasons. Fruit availability was highest in the primary forest than secondary and coastal forest. There was a period of shortage of fruits to ends of the wet season, during which the consumption of not seasonal resources like leaves and shafts increased. The important fruits during this period of shortage were Ficus sp and Licania operculipetala. The several types of forest were used according to the fruit availability, and it was a direct relation between the consumption and the fruit availability.     

Detection of Anaplasmaphagocytophilum in Amblyomma flavomaculatum ticks (Acari: Ixodidae) collected from lizard Varanus exanthematicus imported to Poland

Adults and nymphs of Amblyomma exornatum, A. flavomaculatum, A. latum, Amblyomma spp. and Hyalomma aegyptium, were collected from savannah monitors, royal python (Africa, Ghana) and marginated tortoises (Europe, Greece) imported to Poland, in 2004–2007. Altogether 345 ticks were examined by polymerase chain reaction for rickettsial agents. None of the tested ticks was positive for the gltA gene of Rickettsia spp. DNA of 16S rRNA gene from Anaplasma phagocytophilum was amplified and sequenced from two adult A. flavomaculatum ticks attached to two different specimens Varanus exanthematicus from Ghana. Both PCR amplicons obtained (GQ305134) had 100% sequence homology with A. phagocytophilum sequences deposited in GenBank. This results suggests for the first time that A. flavomaculatum may be vector of this pathogen in Africa. It could be expected that ticks distributed on their hosts may introduce pathogens not yet known to Polish or even European fauna. This study contributes to the overall recognition of the scarcely explored fauna of the exotic ticks transferred to Poland on reptiles from remote destinations.     

Ixodes (Multidentatus) paranaensis n. sp. (Acari: Ixodidae) a parasite of Streptoprocne biscutata (Sclater 1865) (Apodiformes: Apodidae) birds in Brazil

During an ecological study, carried out between 1994 and 1996 with Streptoprocne biscutata (Sclater) (Apodiformes: Apodidae) birds, that inhabit caves in the Quatro Barras County, State of Paran , Southern Brazil, a new tick species of the subgenus Multidentatus was observed. The female, male, nymph, and larva of Ixodes (Multidentatus) paranaensis n. sp., are described. Of the 12 known species of the subgenus Multidentatus, only I. (M.) auritulus Neumann, 1904 and I. (M.) murreleti Cooley and Kohls, 1945 occur in the Neartic region and only I. (M.) auritulus occurs in the Neotropical region. As such, I. (M.) paranaensis n. sp. increases the number of species and the distribution area of the subgenus Multidentatus in the Americas.     

Tetrameres (Gynaecophila) aspicula n. sp. (Nematoda: Tetrameridae), a proventricular parasite of the white-faced ibis Plegadis chihi in Argentina

Tetrameres (Gynaecophila) aspicula n. sp. is described from the proventriculus of the white-faced ibis Plegadis chihi (Vieillot) (Ciconiiformes, Threskiornithidae) from Argentina. The new species is characterised by the absence of spicules, by possessing two ventral rows of extremely small spines in males, extending along the second half of body length, and by the tiny, very feebly developed postcloacal papillae. T. (G.) aspicula n. sp. is compared to the remainder of the species in the subgenus as well as to other species of Tetrameres which lack or possess feebly developed spines. The absence of spicules is a character shared with two other species in the genus, T. (G.) gynaecophila and T. (G.) deccani,from which the new species differs in body size, the arrangement of caudal papillae and the somatic spination in males. A pair of somatic papillae, previously unreported in species of this genus, was found just on or ventral to the lateral line at various regions of the body length. The homology of these structures to other paired somatic papillae described in nematodes is discussed.     

Differential susceptibility of Amblyomma maculatum and Amblyomma americanum (Acari:Ixodidea) to the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae

Nymph and adult ticks from Ambylomma americanum and Ambylomma maculatum were treated with conidia and blastospores of the entomopathogenic fungi Beauveria bassiana (90517) and Metarhizium anisopliae (20500). Fungal suspensions of conidia harvested from potato dextrose plates containing 10⁸ conidia/ml caused greater than 90% mortality in adult A. maculatum but less than 10% mortality in adult A. americanum over a 28 day time course. Similarly, infection with M. anisopliae (10⁸ conidia/ml) resulted in 60 and 15% mortality in A. maculatum and A. americanum, respectively. Nymphs of both tick species were more susceptible to fungal infection reaching mortality rates of almost 100% for A. maculatum and over 35% for A. americanum. Scanning electron microscopy of infected ticks showed rapid attachment, germination, and proliferation of fungal spores on A. maculatum cuticles, and to a much lesser extent on A. americanum cuticles. Pentane extracts of A. americanum cuticle hydrocarbons inhibited germination and hyphal growth of B. bassiana conidia, whereas no inhibition was observed using A. maculatum extracts. Significant mortality towards A. americanum was observed (>60%, 28 days) only when the ticks were treated with B. bassiana directly from the growth medium (10⁷ blastospores/ml, grown for 3–4 days in Sabouraud dextrose + 0.5% yeast extract liquid media). These results indicate tick species display differential susceptibility to the entomopathogenic fungi B. bassiana and M. anisopliae, and that the ability to overcome fungistatic compounds present in the tick epicuticle may determine the likelihood of successful infection and virulence.     

Nutritional values in the diet of white-lipped peccary Tayassu pecari (Artiodactyla: Tayassuidae) in Corcovado National Park, Costa Rica

We determined the potential nutritional levels in 25 species of plants, and in earthworms, that constitute part of the diet of white-lipped peccary (Tayassu pecari) in Corcovado National Park, Costa Rica, from January 1998 to March 1999. The highest content of fat and energy was found in seeds of the Myristicacea family. The highest content of calcium was found in vegetative parts of Dieffenbachia spp. Nutritious contents differed among plant parts (seeds, fruits, stems and leaves). Fat and energy content were larger in seeds and fruits, whereas the largest content of protein was found in fruits and leaves. Mineral content also differed among plant parts. Calcium, potassium and magnesium were higher in leaves whereas copper and zinc were higher in seeds. Differences of diet between white-lipped peccaries in Corcovado and in other tropical regions of Latin America could be partially explained by our results. We found several species with higher fat and energy content than palms, which can explain the low consumption of palm seeds in Corcovado. It is possible that the regular consumption of stems and leaves of some species is related to their high mineral content. Seasonality of reproduction in Corcovado seems to be related not only to fruit availability but also to the nutritional quality of food.     

The parasitism of immature stages of Ixodes loricatus (Acari: Ixodidae) on wild rodents in Argentina

Ixodes loricatus has long been considered with strict-total specificity to New World Marsupials. However, frequent findings of its immature stages on rodents suggest that these vertebrates play an important role in the tick’s life cycle. Aspects dealing with the ecology of Sigmodontinae rodents infestation by I. loricatus are unknown. To contribute to the knowledge of the ecology of this tick species, environmental factors, as well as host species, sex and age, were evaluated to find associations of immature I. loricatus infestation of the most abundant wild rodent species from riparian locations of Buenos Aires province (Argentina). A total of 290 hosts belonging to the subfamily Sigmodontinae were captured and examined for ticks at six locations. The data analysis showed that there was a preference of I. loricatus towards Akodon azarae, but only for those hosts captured in lands not prone to flooding. The results suggest that the host preference of I. loricatus is mainly related to factors such as habitat type and host density.     

New Pudicinae (Trichostrongylina, Heligmosomoidea), Pudica ctenomydis n. sp. parasite of Ctenomys talarum (Rodentia: Octodontidae) from Argentina

A total of 138 nematodes were found in the small intestine of Ctenomys talarum (Octodontidae) from Mar de Cobo, Argentina. A new nematode species, Pudica ctenomydis n. sp., is described. The new species more closely resembles P. pujoli Durette-Desset, 1990, parasite of Microcavia niata Thomas, from Bolivia. It can be distinguished from P. pujoli by the number of ridges and characteristics of the synlophe, the spicular morphology, differences in length between rays 9 and 10, and by the presence of a symmetrical caudal bursa and a cuticular expansion surrounding the body between vulva and anus in females.     

Euryconema brevicauda n. sp. (Oxyurida: Thelastomatidae) a parasite of the mole cricket Neocurtilla claraziana (Orthoptera: Gryllotalpidae) in Argentina

Euryconema brevicauda n. sp. parasitizing the mole cricket Neocurtilla claraziana found in Buenos Aires province, Argentina, is described and illustrated. This species is characterized by the male having 3 pairs of genital papillae, 1 pair preanal and 2 pairs postanal, and a short, conical-shaped tail.