Oxytocin plus antibiotics: A synergism of potentiation to enhance bovine uterine contractility

This in vitro study investigates the modulatory effect of three antibiotics (amoxicillin, enrofloxacin, and rifaximin) on contractility of the bovine uterine tissue, in follicular and luteal phases. The evaluation of the effects of these antibiotics (104 M) was performed on oxytocin-induced contractility. The decision to test these antibiotics with the oxytocin (106 M) comes from the reported ability of these combinations of hinder the antibiotic resistance and the formation of bacterial biofilms. The procedures were carried out in isolated organ bath, and the contractile functionality of the strip throughout the experiment was evaluated after a dose of carbachol (105 M). The results demonstrate the different modulatory activity of these antibiotics, on the plateau of contraction induced by oxytocin, in both phases of the estrus cycle. The differing individual antibiotic effects of our testing made it possible to identify, only in some cases. Rifaximin in the follicular phase and enrofloxacin in both phases of the estrous cycle, induced a synergistic enhancement (potentiation) of uterine strip contraction induced by oxytocin. This result is thought important because these associations might enable, in vivo, a simultaneous increase of uterine cleaning and the antimicrobial action on bacteria in planktonic form and of those organized in biofilms

Effect of neostigmine on contractility of equine pre-ovulatory follicles: an in vitro study.

In this study, the Authors investigated the modulatory effect of three single doses (106, 105, and 104 M) of neostigmine on the spontaneous contractility of equine pre-ovulatory follicles in an isolated organ bath, to establish the relationship between this acetylcholinesterase inhibitor and ovulation, in the mare. The results indicate that neostigmine increases pre-ovulatory contractility in equine follicles at each dose, but in a different manner. Indeed, the rise in contractility induced by neostigmine at 106 M and 104 M was phasic, while at 105 M it was tonic. The data obtained indicate possible implications of these drugs in the pharmacological modulation of equine ovulation

Lidocaine decreases the xylazine-evoked contractility in pregnant cows

The objective of this in vitro study was to evaluate and compare the effects of xylazine on basal uterine contractility of bovine pregnant uterine strips and that of lidocaine on xylazine-sensitized bovine pregnant uterine strips, at different stages of pregnancy. Basal contractility was evaluated in an isolated organ bath and the functionality of the strips throughout the experiment was evaluated using a dose of carbachol (10−5 M). Uterine motility, expressed with amplitude, frequency of contractions as well as the area under the curve, was recorded in different stages of pregnancy and data were collected at 15-min intervals (5-min before and 5-min after xylazine administration and 5-min after lidocaine addition on the plateau contraction induced by xylazine). Uterine motility increased in all the stages of pregnancy after xylazine addition and gradually decreased after treatment with lidocaine. These data suggest that lidocaine might decrease the tonic effect induced by xylazine on bovine pregnant uteri

FLUOROQUINOLONE AND OVARIECTOMY IN THE BITCH: PHYSIOLOGY OF THE IMMUNE SYSTEM AS TO CD56 AND CD16 EXPRESSION

Natural killer (NK) cells are innate lymphoid cells which act against a variety of pathogens and tumours. Phenotypically they are characterized by surface markers named cluster designation (CD) antigens. CD56 and CD16 are recognized as specific NK markers in the dogs as well as in humans. Surgical interventions suppress NK cells both in rats and humans. In this direction, it has been shown that an antibiotic regimen (amoxicillin, benzylpenicillin/dihydrostreptomycin, sulfametazine/sulfamerazine/ sulfathiazole, enrofloxacin, lincomycin/spectinomycin) administered only twice is effective in preventing infections after laparatomic ovariectomy, in the bitch. On these grounds, this research will show that the administration of a fluoroquinolone (5 mg/kg of enrofloxacin, Baytril®, Bayer, Milan, Italy) one hour before and at the end of ovariectomy is able to increase CD56 and CD16 expression levels. Moreover, the antibiotic administration modifies the relative expression levels of the two CD; thus suggesting that the fluoroquinolone employed enhances the activation of a specific subset of NK cells mainly involved in body recovering during the post operative period as already observed in humans

Effects of d-cloprostenol on different layers and regions of the bovine uterus during the follicular and luteal phases.

Introduction: D-cloprostenol is a synthetic PGF2a, commonly used in bovine reproduction, that increases myometral contractility. However, little is known regarding its contractile behaviour and how it depends on the reproductive state and uterine topography (regions and muscular layers). Hypothesis and objectives: These aspects would affect the action of d-cloprostenol on the uterus. Therefore, we hypothesize a possible use of this drug at the time of artificial insemination, to improve conception rates and, in the post-partum, in order to accelerate uterine involution in dairy cattle. The purpose of the present study was to investigates the modulatory effect of d-cloprostenol on contractility of the bovine uterine region (horn and corpus) and their muscle layers (circular and longitudinal), in follicular and luteal phases. To our knowledge, motility effects of d-cloprostenol on different regions from healthy bovine uterus have not been described up to now. Materials and methods: Uterine specimens were collected from uterine body and horn of cattle in the follicular (n ¼ 28) and luteal phase (n ¼ 32) of the estrous cycle at slaughter. Two strips were prepared from each regions corresponding to the circular and the longitudinal muscular layers, respectively. Samples were cultured in an organ bath, exposed to synthetic prostaglandin (1 mM d-cloprostenol) and their contractile activity was monitored for 10 min. The functionality of the strip throughout the experiment was tested by a dose of carbachol (105 M). Results: The mean basal amplitude of contractions was higher in the follicular compared to the luteal phase in uterine horn samples, but not in muscles collected from the uterine body. The amplitude of contractions increased after d-cloprostenol administration in all tissues with a greater increase in samples from cattle in the follicular phase. The frequency of contractions increased after d-cloprostenol administration in longitudinal but not in circular fibrees. Conclusion: The contractile responses to d-cloprostenol in both horn and corpus were strongest in the circular muscles but weak in the longitudinal muscles

Dynamics of the progesterone and cholesterol concentrations within the bovine corpus luteum cavity

The aim of this study was to examine the concentrations of progesterone (P4) and cholesterol (CHOL) in fluid of cavitary corpus luteum(CL) and in serumof dairy cattle. Cavitary corpora lutea, collected fromcows at a local abattoir, were divided in four stages of development, based on days of the estrous cycle (stage I: 1–4 days; stage II: 5–10 days; stage III: 11–17 days; stage IV: 18–20). Fluid of the their cavity was aspirated and P4 and CHOL concentrations were evaluated. The concentrations of P4 in CL cavity fluids were very high (1640–4666.67 ng/mL) and showed a peak at the stage III. CHOL values were similar to those of serum and the highest levels were found in the stage I

Application of an innovative technique for unilateral ovariectomy in dairy cows

This report describes an innovative unilateral ovariectomy technique for the surgical treatment of follicular cysts in dairy cows. Five cows, with a diagnosis of follicular cysts, were submitted to unilateral ovariectomy via a paralumbar fossa approach, in standing position. The linear cutter proved useful for clamping the ovary, stapling the vessels and cutting in one stroke, thus reducing surgery times. After unilateral ovariectomy, all cows underwent heat 7–30 days after surgery, and three cows became pregnant. All cows showed increased milk production. The results of this case report showed that flank ovariectomy, performed in this way, is an efficient, low-risk technique for surgical treatment of follicular cysts in dairy cows

Rinvenimento del solo cranio fetale nell'utero di una bovina, con presunta gravidanza di sei mesi

La macerazione fetale è un processo di decomposizione dei tessuti molli, che si verifica in tutte le specie, ma con un’incidenza maggiore in quella bovina, a seguito della prematura lisi del corpo luteo gravidico, del conseguente processo infiammatorio e della colonizzazione batterica del feto. Questo lavoro descrive il rinvenimento del solo cranio fetale nel corno uterino di una bovina Frisona di 4 anni, con presunta gravidanza di circa 6 mesi. Circa 150 giorni dopo la F.A., la bovina aveva manifestato uno scolo vulvare brunastro e, alla palpazione ed all’ecografia transrettali effettuate, si è percepita e visualizzata la presenza di una massa ovale, dura, compatta, iperecogena, di 5-6 x 7 cm, nel corno uterino sinistro. La doppia somministrazione per via intramuscolare di 25 mg di dinoprost (Dinolytic®, Pfizer, Italia) a distanza di 24 ore non aveva determinato dilatazione cervicale. La somministrazione, in terza giornata, per via epidurale, di 12,5 mg dello stesso farmaco, aveva determinato una dilatazione cervicale di circa 2 cm, insufficiente a garantire l’espulsione della massa. Si è optato per l’isterotomia che ha consentito l’estrazione di un cranio fetale, con i due emi-corpi mandibolari e porzione dell’arcata orbitaria, ascrivibile, per dimensioni, ad un’epoca gestazionale di circa 120-140 giorni. L’insolito reperto potrebbe essere il residuo, andato incontro a macerazione, di un feto abortito ed espulso parzialmente. Ciò potrebbe essersi verificato a seguito di una dilatazione incompleta e transitoria della cervice, con successiva contrazione e chiusura, e conseguente necrosi e distacco del corpo fetale aldilà dell’ostio cervicale esterno

Kisspeptin and bovine follicular cysts

The aim of this study was to investigate kisspeptin (Kp) and sexual hormone blood concentrations in healthy dairy cows (H) and in cows diagnosed with ovarian follicular cysts (FC). Forty dairy cows were enrolled in this study and divided in 2 groups of 20 subjects each. All cows underwent blood collection on the day of diagnosis and on that of heat detection, respectively. Kisspeptin 10, estradiol, and progesterone blood concentrations were assessed. All the parameters were higher in Group FC than in Group H. These results suggest that the higher steroid levels found may have determined the increase in Kp secretion in the cystic cows. This, in turn, may have directly or indirectly stimulated the sustained Luteinizing Hormone (LH) release, known to occur in dairy cystic disease

Kisspeptin and bovine follicular cysts

The aim of this study was to investigate kisspeptin (Kp) and sexual hormone blood concentrations in healthy dairy cows (H) and in cows diagnosed with ovarian follicular cysts (FC). Forty dairy cows were enrolled in this study and divided in 2 groups of 20 subjects each. All cows underwent blood collection on the day of diagnosis and on that of heat detection, respectively. Kisspeptin 10, estradiol, and progesterone blood concentrations were assessed. All the parameters were higher in Group FC than in Group H. These results suggest that the higher steroid levels found may have determined the increase in Kp secretion in the cystic cows. This, in turn, may have directly or indirectly stimulated the sustained Luteinizing Hormone (LH) release, known to occur in dairy cystic disease