A. Giammarino

Degranulation of mast cells due to compound 48/80 induces concentration-dependent intestinal contraction in rainbow trout (Oncorhynchus mykiss Walbaum) ex vivo.

Rainbow trout (Oncorhynchus mykiss) intestinal strips (n = 10) were mounted in an isolated organ bath and the effect of incremental doses of compound 48/80 was recorded. Compound 48/80 induced concentration-related contraction in all the examined strips following a sigmoidal dose-response curve fit. Values for maximal contraction (E(max) , g cm(-2)), negative logarithm of the EC(50) (pD(2)), and hill slope were, respectively (mean±standard error), 12.88 ± 0.51, 1.88 ± 0.05, 1.49 ± 0.27. The histological modification induced on mast cells (MCs) due to compound 48/80 was characterized by mean of gray-levels and texture analysis. Significant differences were observed between gray-levels values (Linear mixed model, P<0.01), contrast, and entropy (Linear mixed model, P<0.05) of MCs from compound 48/80-treated strips compared with MCs from untreated strips. Moreover, maximal intestinal contraction (due to compound 48/80) correlates positively and significantly (Pearson and Spearman correlations, P<0.05) with degranulation intensity determined by means of gray-levels analysis. Four antisera were tested on intestinal sections and no MCs positive to serotonin, substance P, met-enkephalin, and bombesin were found. This study demonstrates that compound 48/80 induces the degranulation of trout intestinal MCs ex vivo, and that the aforementioned degranulation promotes a concentration-dependent intestinal contraction.

Comparing Therapeutic Efficacy between Ivermectin, Selamectin, and Moxidectin in Canaries during Natural Infection with Dermanyssus gallinae

The aim of this study was to compare the efficacy of three spot‐on drugs on canaries during Dermanyssus gallinae natural infections and during the breeding season. Three groups of canary couples (seven couples each) were included: group A was treated with ivermectin, B with selamectin, and C with moxidectin. All the drugs were administered topically infrascapularly. The parasitic charge was estimated before the treatment (t0) and after 8 (t1), 16 (t2), 24 (t3), and 32 (t4) days following the initial treatment. No significant differences were detected among the three tested drugs for the five repeats for each of the four mite stages (egg, larva, nymphs, and fed and unfed adults). With regard to the decrease in the mean numbers of red mites, ivermectin and selamectin exerted their efficacy at t2, contrary to moxidectin at t3.

Use of a Synthetic GnRH Analog to Induce Reproductive Activity in Canaries {Serinus canaria)

ABSTRACT In this study, we evaluated the effects of a transcutaneously administered gonadotropin-releasing hormone analog (lecirelin) on the reproductive activity of the canary (Serinus canaria). Two groups of 20 pairs of canaries were treated with increasing concentrations of lecirelin delivered in a cream vehicle; one group was exposed to a natural photoperiod, and the other group received additional photostimulation. Two groups of 10 pairs of canaries served as controls; one group was exposed to an artificially lengthened photoperiod, and the other group was maintained under a natural photoperiod and treated with a nonmedicated cream vehicle. In all canaries treated with lecirelin, the onset of reproductive activity occurred significantly earlier than in either control group.

The effect of GnRH on in vitro bovine myometrial activity

The aim of this study was to evaluate, in vitro, the effects of increasing concentrations of GnRH on spontaneous mechanical activity patterns of uterine smooth muscle preparations of cows during the follicular and the luteal phases of the oestrus cycle. Uterine smooth muscle strips from 14 cows in follicular and 9 in luteal phase were collected immediately after slaughter and processed within 60 min from collection. Two strips of the same uterus were mounted in an isolated organ bath with two chambers to evaluate the role of decapeptide GnRH on spontaneous myometrial contractility. After equilibration period at 20 mN resting tension, the mechanical activity of the uterus was recorded for 10 min and the mean contractile force (MCF) was calculated. Then GnRH antagonist (antide) was added to one chamber at fixed concentration (10(-4)mol) and allowed to diffuse in solution and make contact with the strips. Subsequently, GnRH was added to the two baths at the same time at increasing concentration and MCF was recorded for 10 min. The effect of GnRH on spontaneous myometrial activity was evident only in the strips from subjects in follicular phase. Our results are suggestive of the presence of GnRH receptors in bovine myometrial tissue. The involvement of GnRH on uterine contractions at mating can be postulated.

Evaluation of in vitro GnRH effects on spontaneous contractions of the bovine myometrium

Evaluation of in vitro GnRH effects on spontaneous contractions of the bovine myometrium M. Manera & D. Robbe & L. Grotta & M. P. Demontis & A. Giammarino Published online: 1 July 2009

Influence of 17β-Estradiol and Progesterone on Myometrial Strips of Immature Lambs: Experimental

A. Giammarino1,∗, D. Robbe2 and M. Amorena1 1Department of Food Science, Section of Veterinary Pharmacology and Toxicology; Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy; 2Department of Clinical Veterinary Science, Section of Obstetrics, Gynaecology and Animal Reproduction, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy ∗Correspondence: E-mail: labfv@unite.it