This paper aims to describe a case of trombiculosis in llamas from the Puna region of Argentina caused by Eutrombicula cochinocaensis. Trombiculosis is a parasitic infestation caused by the larval form of trombiculid mites, commonly known as chigger mites. Six adult llamas out of eighteen (33%) were infested and showed dermatitis, hyperemia, and crusts together with an orange-dotted pattern.
View Article and Find Full Text PDFThere are few studies that classify and characterize the morphometric and immunohistochemical features of goitre in bovine thyroid glands (TGs). We investigated 39 bovine TGs (fetuses [9], stillbirths [18], neonates [12]) born to dams with low T4 hormone levels and no iodine supplementation and 10 (fetuses [3], stillbirths [3], neonates [4]) born to dams with normal T4 levels and supplemented with iodine. Body weight (BW), TG weight (TGW), TGW:BW ratio and histological lesions were determined.
View Article and Find Full Text PDFAlpaca is a South American camelid, particularly present in Peruvian highlands, where oxygen concentration and atmospheric pressure are very low. Due to this fact, gestational physiology has adapted to preserve the conceptus' and mother's health. In this context, several cellular and molecular features play an essential role during and at the end of gestation.
View Article and Find Full Text PDFIn Brief: Current research on the genomics, ecology and reproductive biology of hystricomorph rodents relies on the pioneering studies of B J Weir and I W Rowlands. We show the enduring influence of a symposium on hystricomorph biology held 50 years ago.
Abstract: The rodent suborder Hystricomorpha comprises seven families from Africa and Asia and ten from South America, where they have undergone an extensive radiation and occupy a variety of biomes.
Reproductive specializations in caviomorphs (infraorder Hystricognathi), are very peculiar within the Order Rodentia. These include long gestations, the birth of offspring with an extreme degree of precociality, and short lactation periods. This study describes the embryo-placental relationship of viable implantation sites (IS) of the plains viscacha, Lagostomus maximus, after 46 post-coital days.
View Article and Find Full Text PDFUsing morphological and molecular studies, the life cycle of (Cestoda: Taeniidae) was elucidated, involving subterranean rodents (Ctenomyidae) as intermediate hosts, and the lesser grison, (Mustelidae), as definitive host. Metacestodes (cysticerci and polycephalic larvae) were found mainly in the liver but also in spleen, pancreas, lungs and small intestine of 2 species of tuco-tucos ( spp.) from Chubut, Argentina.
View Article and Find Full Text PDFThe main evolutionary milestone in the oviparity-viviparity transition is placentation. The placenta is an organ with great morphological diversity among eutherians. The expression of different glycosidic residues (Gr) in the near-term placenta constitutes its glycotype.
View Article and Find Full Text PDFThe process of aging is the result of progressive loss of homeostasis and functional body impairment, including the central nervous system, where the hypothalamus plays a key role in regulating aging mechanisms. The consequences of aging include a chronic proinflammatory environment in the hypothalamus that leads to decreased secretion of gonadotropin-releasing hormone (GnRH) and impairs kisspeptin neuron functionality. In this work, we investigated the effect of insulin-like growth factor 1 (IGF1) gene therapy on hypothalamic kisspeptin/GnRH neurons and on microglial cells, that mediate the inflammatory process related with the aging process.
View Article and Find Full Text PDFSpontaneous embryonic death is a conserved reproductive event in Eutherians. The macro and microscopic characteristics of this type of death are similar between the different taxa. However, in the hystricomorphic rodent plains viscacha (Lagostomus maximus) is exceptional in terms of massiveness (80% embryonic resorption).
View Article and Find Full Text PDFCaviomorpha are an exceptional group among rodents due to their extended gestational period and the delivery of precocial offspring. Among them, Lagostomus maximus is characterized by its polyovulation, polyembryony, and the highest embryonic death known in mammals. Its chorioallantoic placenta is hemomonochorial, an ancestral character among rodents.
View Article and Find Full Text PDFEmbryonic death followed by resorption is a conserved process in mammals. Among the polyovular species, Lagostomus maximus (plains viscacha) constitutes a model of early and physiological embryonic death, since out of a total of 10-12 implants, 8-10 are resorbed during early/intermediate gestation, surviving are only the most caudal implantations of each uterine horn. This regular reproductive event is unique to this species, but many characteristics of the implantations during the early gestation of L.
View Article and Find Full Text PDFAtlantoraja platana is an oviparous skate endemic to the south-west Atlantic Ocean, and is one of the skate species most exploited by local industrial bottom trawl fisheries. Oviparous elasmobranchs encapsulate their eggs in complex egg cases produced by the oviductal gland (OG). This organ is exclusively present in these fishes and comprises four distinct zones: club, baffle, papillary and terminal.
View Article and Find Full Text PDFThe uterus is an organ with great plasticity due to the morphological and physiological changes it experiences during the estrous cycle and pregnancy. In mammals, pregnancy requires diverse sex hormones, growth factors and cytokines, among others, for promoting uterine remodeling to favor implantation, placentation, and embryo/fetus survival and growth. The hystricognathi rodent Lagostomus maximus (plains viscacha) has a high rate of embryonic resorption.
View Article and Find Full Text PDFThe objective of this study was to evaluate the effects of plasma progesterone (P) concentrations during eCG-ovarian follicular superstimulatory treatment performed in early luteal phase and estradiol concentrations during peri-ovulatory period on ovarian response, number and embryo quality. On Day -2, females (n = 75) having a follicle ≥7 mm were treated with GnRH to induce ovulation. On Day 0, females that had ovulations (n = 54) were treated with 1000 IU eCG and were assigned to one of two treatments: (1) intravaginal device (ID) containing 0.
View Article and Find Full Text PDFThis study reports the histochemistry and the distribution of glycoconjugates (GCs) in the zona pellucida (ZP) of preantral, secondary, tertiary, polyovulatory and atretic follicles of ovaries from non-pregnant (NPr) and pregnant (Pr) females of Lagostomus maximus. GCs were studied using histochemical and lectin histochemical methods. The viscacha ZP was positive to all the histochemical techniques.
View Article and Find Full Text PDFThe objectives of the present study were to determine the effects of exogenous GnRH administered 7 days after breeding on the formation of an accessory corpus luteum (ACL), plasma progesterone (P) concentrations and pregnancy rates. Adult females (n = 71) having a follicle ≥ 7 mm in diameter in the ovary were naturally mated (Day 0). On Day 7, ultrasonic examination was performed to confirm the occurrence of ovulation as evidenced by presence of an induced corpus luteum (ICL).
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