17 research outputs found
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
IMPACT OF PURSE SEINE CLUPEOIDS FISHERY ON JUVENILES BLUEFIN TUNA (THUNNUS THYNNUS) IN THE SOUTHERN ITALIAN SEAS
Età ed accrescimento di giovanili di tonno rosso (Thunnus thynnus L. 1758) nei mari meridionali d’Italia
Histochemical analysis of sialoglycoconiugates in the luminal Surface of the Ampulla of Horse Oviduct
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
endothelial area and microcascular density in a canine non hodgkin's lymphoma:an interspecies model of tumor angiogensis
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