Residue study of ivermectin in plasma,milk, and mozzarella cheese following subcutaneous administration to buffalo (Bubalus bubalis)

The distribution of ivermectin in buffalo plasma and milk after administration of a single subcutaneous dose (0.2 mg kg(-)(1) b.w.) was studied. Ivermectin reached the maximal concentration in plasma (28.5 +/- 1.7 ng mL(-)(1)) and milk (23.6 +/- 2.6 ng mL(-)(1)) after 2.4 +/- 0.32 and 2.8 +/- 0.44 days, respectively. The drug showed a parallel disposition in milk and plasma, with a ratio of 1.12 +/- 0.16. Ivermectin concentrations were detected in mozzarella cheese obtained from milk collected on days 1, 3, 4, and 20 following administration. The highest values (81.4 +/- 3.26 ng g(-)(1)) were found in the cheese produced on day 3 and were 4-fold higher than those present in the milk.     

Effects of Water pH and Hardness on Infection of Silver Catfish,Rhamdia quelen,Fingerlings by Ichthyophthirius multifiliis

The aim of this study is to determine the effect of (1) different pH levels (5, 6, 7, 8, and 9) with water hardness 20 mg/L CaCO₃ and (2) pH 5 and 7 with varying water hardnesses (20, 60, and 120 mg/L CaCO₃) on the intensity of infection by Ichthyophthirius multifiliis in fingerlings of the silver catfish, Rhamdia quelen. In Experiment 1, the lowest and highest mortality rates were observed in fingerlings exposed to pH 5 and 9, respectively; in Experiment 2, fish kept at pH 5 and 7 with hardness 20 mg/L CaCO₃ showed significantly lowest and highest cumulative mortality, respectively, than those maintained in other conditions. The lowest intensity of trophonts/fingerling was observed at pH 5 and hardness 20 mg/L CaCO₃ in both experiments. We conclude that infection by I. multifiliis is less severe in silver catfish maintained at pH 5 and hardness 20 mg/L CaCO₃. High water hardness led to an increased intensity of trophonts and decreased survival in silver catfish kept at pH 5, but decreased intensity of trophonts and improved survival when the fish were kept at pH 7.     

Impact of new measured Mediterranean mineralization rates on the fate of simulated aquaculture wastes

In order to provide values of key parameters in aquaculture waste degradation modelling specifically for the Mediterranean, sampling campaigns were carried out in 2006. Accurate measurements of particulate carbon input and benthic respiration rates were performed using sediment traps and intact core incubations. The in situ measurements, compared with data from Atlantic salmon production, showed lower carbon flux and oxygen consumption, while a greater degradation capability was observed. Moreover, a temperature dependence of the benthic parameters was highlighted. Successively, the model Finite Organic Accumulation Module was used for an accurate comparison between different parameterizations. Finite Organic Accumulation Module simulates the organic carbon degradation and the net carbon accumulation on the sediment, yielding a benthic state index. In comparison with previous results, there was a decrease in benthic impacts due to minor inputs of carbon and higher mineralization rates. Moreover, a seasonal variation could be observed in the organic carbon concentration. Nevertheless, the new results remain consistent with the old ones on two points: (a) the negligible benthic impact of faeces with respect to uneaten feed and (b) the dependence of that impact on the different feed release conditions.     

Anesthetic activity of the essential oil of Aloysia triphylla and effectiveness in reducing stress during transport of albino and gray strains of silver catfish,Rhamdia quelen

This study investigated the efficacy of the essential oil (EO) of Aloysia triphylla as an anesthetic for albino and gray strains of silver catfish, Rhamdia quelen. Juveniles were exposed to concentrations between 20 and 800 μL L^?1 EO of A. triphylla to evaluate time of induction and recovery from anesthesia. In another experiment, both strains were divided into four groups such as 0 (control), 30, 40, or 50 μL L^?1 EO and transported for 5 h. The longest time for anesthetic induction and recovery was observed in the albinos. Both strains reached anesthesia in the 100–800 μL L^?1 (11.1–1.24 min) range, without mortality, being 200 μL L^?1 the best response considering time to anesthesia (5.35 min). Albinos transported with all EO concentrations showed higher values of carbon dioxide in the water of transport, but lower levels were observed in grays transported with 40 and 50 μL L^?1 EO when compared to control fish. The same concentrations did not prevent significant whole-body cortisol rise at the end of transport in the albino strain. Juveniles of both strains transported with EO presented lower ion loss to the water compared to control fish. The EO of A. triphylla is an effective anesthetic for albino and gray silver catfish. This EO increases whole-body cortisol levels in the albino strain, but as it reduces net ion loss as in the gray strain, it can be also recommended for transport.     

Three-dimensional microvascolature remodeling study of pig periovulatory follicles using vascular corrosion casts

Veterinary Research Communications -     

Midazolam oxidation in cattle liver microsomes: The role of cytochrome P450 3A

In humans, the cytochrome P450 3A (CYP3A) subfamily is involved in midazolam (MDZ) biotransformation into 1′- and 4-hydroxy metabolites, and the former serves as a probe for CYP3A catalytic activity. In veterinary species is still crucial to identify enzyme- and species-specific CYP substrates; thus, the aim of this study was to characterize MDZ oxidation in cattle liver. A HPLC-UV method was used to measure 1′- and 4-hydroxy MDZ (1′- and 4-OHMDZ, respectively) formation in cattle liver microsomes and assess the role of CYP3A by an immunoinhibition study. Moreover, MDZ hydroxylation was evaluated in 300 cattle liver samples and results were correlated with testosterone hydroxylation. Formation of both metabolites conformed to a single-enzyme Michaelis–Menten kinetics. Values of V_max and K_m were 0.67 nmol/min/mg protein and 6.16 μM for 4-OHMDZ, and 0.06 nmol/min/mg protein and 10.08 μM for 1′-OHMDZ. An anti-rat CYP3A1 polyclonal antibody inhibited up to 50% and 94% 1′- and 4-OHMDZ formation, respectively. MDZ oxidation in liver microsomes was poorly correlated with testosterone hydroxylation. In conclusion, cattle metabolized MDZ to 1′-OHMDZ and 4-OHMDZ. The immunoinhibition results indicated a major contribution of CYP3As to 4-OHMDZ formation and the involvement of other CYPs in 1′-OHMDZ production, paving the way for further investigations.     

Correlation between osteoarthritic changes in the stifle joint in dogs and the results of orthopedic,radiographic, ultrasonographic and arthroscopic examinations

Osteoarthritis (OA) is a chronic, degenerative disease affecting the articular cartilage and subchondral bone that causes pain and inhibits movement. The stifle’s joint fibrous capsule contains the synovial membrane, which produces cartilage nutrients. A ruptured cranial cruciate ligament injures the joint and produces OA. Osteoarthritis diagnosis starts with clinical radiographic and ultrasonographic tests, although the latter is not used very much in dog and cat clinics for this purpose. The objective of this study was to establish the correlation among the results of orthopedic, radiographic, ultrasonographic examinations and structural anatomical changes revealed by arthroscopic evaluation to diagnose stifle joint OA and determine risk factors in the dogs affected. Of 44 clinical cases of OA included in the study, 88.64% had ruptured of cranial cruciate ligaments. The correlation between synovial fluid effusion and osteophytosis was of 0.84. It was concluded that there is good diagnostic agreement between synovial fluid effusion and osteophytosis when dealing with stifle joint OA. Risk factors for dogs regarding the development of stifle joint OA included: ruptured cranial cruciate ligaments or patella luxation, female dogs and weight over 10 kg.     

An ovine preimmune foetal model to study the effect of cellular therapies for myocardic diseases

The ovine foetus is an ideal model for preclinical medical studies of cell therapies. It allows us to follow the behaviour of repairing cells inserted into a favourable physiological microenvironment in an animal species more closely related to humans than the rat or rabbit. In addition, the preimmune foetus is able to support cell engraftment by eliminating the problems of tissue rejection. Labelled fibroblasts were transplanted into the myocardium of preimmune foetuses, injecting through a disposable bowed mouth pipette into the left ventricular apex. Two weeks later, foetuses were isolated by laparotomy and each heart was collected and morphologically analyzed. No cases of abortion or postoperative complications in mothers or foetuses occurred. Macroscopically, the isolated hearts did not display any abnormality apart from a small petechia at the injection site. Tissue sections did not show any sign of acute tissue inflammation and viable labelled cells were easily identified among myocardiocytes. This model system guarantees a reduced damage in the engrafted tissue, a high survival and easy retrieval of the injected cells. The direct injection of cells into the preimmune ovine foetus myocardium can be satisfactorily performed to control tissue delivery and to reduce the risk of cell loss and dispersion.     

Clinical and Laboratory Findings in Equine Piroplasmosis

The objective of this study was to evaluate equine piroplasmosis (EP) as a cause of morbidity in horses in Sardinia (Italy), describe the clinical signs and altered hematologic and biochemical parameters, and illustrate response to different treatments. Among 44 horses suspected of tick-borne disease, 38 were polymerase chain reaction (PCR) positive for Theileria equi (n = 27) or Babesia caballi (n = 6), whereas five were positive for both protozoans. Typical clinical features of piroplasmosis were seen in some of the horses, whereas others had nonspecific mild symptoms. Hematologic findings revealed involvement of the three blood cell lineages (anemia, leukopenia or leukocytosis, thrombocytopenia), and biochemical variations were related to increased bilirubin, alteration of serum phosphorus, and hypoalbuminemia. We suggest that the two protozoans are the most important causative agents of equine tick-borne disease in this geographic area, and we observe that different clinical features are associated with the disease; in addition to the typical aspects of piroplasmosis, characterized by fever, pale mucous membranes, and icterus, we can signal other nonspecific mild signs such as weight loss, weight loss associated with an insignificant leukopenia, or weight loss associated with depression, anorexia, and mild hyperbilirubin. The study is intended as a practical contribution for veterinary practitioners because it describes different clinical presentations and laboratory findings of EP, suggests diagnostic and therapeutic approaches to the disease, and shows diffusion of the disease in a Mediterranean region.