Brain morphology and immunohistochemical localization of the gonadotropin-releasing hormone in the bluefin tuna, <i>Thunnus thynnus</i>

The present study was focused on the morphology of the diencephalic nuclei (likely involved in reproductive functions) as well as on the distribution of GnRH (gonadotropin-releasing hormone) in the rhinencephalon, telencephalon and the diencephalon of the brain of bluefin tuna (Thunnus thynnus) by means of immunohistochemistry. Bluefin tuna has an encephalization quotient (QE) similar to that of other large pelagic fish. Its brain exhibits well-developed optic tecta and corpus cerebelli. The diencephalic neuron cell bodies involved in reproductive functions are grouped in two main nuclei: the nucleus preopticus-periventricularis and the nucleus lateralis tuberis. The nucleus preopticus-periventricularis consists of the nucleus periventricularis and the nucleus preopticus consisting of a few sparse multipolar neurons in the rostral part and numerous cells closely packed and arranged in several layers in its aboral part. The nucleus lateralis tuberis is located in the ventral-lateral area of the diencephalon and is made up of a number of large multipolar neurones. Four different polyclonal primary antibodies against salmon (s)GnRH, chicken (c)GnRH-II (cGnRH-II 675, cGnRH-II 6) and sea bream (sb)GnRH were employed in the immunohistochemical experiments. No immunoreactive structures were found with anti sbGnRH serum. sGnRH and cGnRH-II antisera revealed immunoreactivity in the perikarya of the olfactory bulbs, preopticus-periventricular nucleus, oculomotor nucleus and midbrain tegmentum. The nucleus lateralis tuberis showed immunostaining only with anti-sGnRH serum. Nerve fibres immunoreactive to cGnRH and sGnRH sera were found in the olfactory bulbs, olfactory nerve and neurohypophysis. The significance of the distribution of the GnRHimmunoreactive neuronal structures is discussed

Cross sectional study for pestivirus infection in goats in southern Italy

Pestiviruses have a worldwide distribution where ruminants farming is extensive and infection in their hosts can vary from subclinical manifestations to severe clinical signs. Although biomolecular methods are successfully employed for pestiviruses identification, they require the presence of the virus at the time of sampling. Because persistent infection is unusual in goats and acute infection is transient, for a retrospective assessment serology is the most useful approach to evaluate pestiviruses spread among ruminants. The prevalence of pestiviruses in the Italian goat population was the main target of the study and the possible influence of the co-habitation with cattle on the seropositivity of goats was taken into account. A total of 7096 sera from healthy goats were tested using an indirect ELISA. The positive samples were confirmed with a virus neutralization (VN) test and were screened for BDV too. The ELISA assay identified 57 farms (33.13%) with positive goats and an overall seropositivity of 1.63%, higher in Calabria (1.74%, 95% CI 1.68% to 1.79%) than in Apulia (1.59%, 95% CI 1.52% to 1.66%). A higher variability among farms was observed, with a significant influence of multi-species (goat and cow) grazing. Despite the huge economic losses, the impact on small ruminant productions in Italy has not yet been assessed and pestivirus infection is largely underestimated and scarcely considered. Nevertheless, the focus on pestiviruses of small ruminants should be strengthened. Considering that pestivirus infections are often subclinical, serological surveillance, the prerequisite for the implementation of control programmes, should be strongly recommended and should be considered in any pestivirus eradication programme, especially in areas such as the Southern Italy, where small ruminants farming is predominant

Male reproductive physiology of Paracentrotus lividus: monthly and seasonal evaluations to study the effects of the environment on gonadal development and sperm cells kinetic

Paracentrotus lividus is a model species for research in different areas, it is also important for modern aquaculture interested in breeding innovative species for greater product diversifications and reduction of the wild stock fishing pressure. This Echinoid was considered a seasonal niche product in the past; nowadays it is highly required on the market for the nutritional characteristics (high protein and low fat) of gonads, the edible part. Our work aims at optimizing farm technics by the study of the habitat impact on P. lividus male reproductive physiology. We correlated environmental variables of the fishing area (temperature, humidity, photoperiod, water temperature, moon phases) to reproductive parameters (morphological gonadal development, sperm cells kinetic). We analyzed data to highlight the relevance, for reproduction, of the length (month or season) of the observations. The significance of this work to the field of aquatic sciences is to drive aquaculture facilities in choosing the desirable period to recover the best spermatozoa with highest total and progressive motility. Moreover setting useful parameters to mimic the best environmental conditions, the highest gonadal development could be reached. This could also promote gametes exchanges between aquaculture facilities in the world taking advantage of the environment dependent gametes maturity

Lectin histochemistry on the apocrine sweat glands of dog dorsal skin

The secretory segment of apocrine sweat glands of the dog dorsal skin was studied by means of both conventional carbohydrate histochemistry and lectin histochemistry. Conventional glycoconjugate histochemistry revealed mostly neutral glycoproteins and partly acidic non sulphated glycoproteins in the apical protrusions of the secretory cells as well as in the luminal secretions of the glands. The lectin histochemistry showed Con A binding sites in the whole cytoplasm of the secretory cells. The supra-nuclear granules (probably including also Golgi elements) were labelled by SNA, MAA, RCA120, Con A, and GSA I-B4 thus indicating the presence of sialylated or asialylated N-linked oligosaccharides. The luminal surface of secretory cells reacted with all the lectins employed except with SBA. The apocrine protrusions revealed a general decrease in the lectin staining intensity, and lacking of GSA I-B4, UEA-I, and LTA reactivity. The luminal homogeneous matrix labelled SNA, WGA, GSA II, and GSA I-B4