Anthelmintic resistance: is a solution possible?

More than 50 years after anthelmintic resistance was first identified, its prevalence and impact on the animal production industry continues to increase across the world. The term "anthelmintic resistance" (AR) can be briefly defined as the reduction in efficacy of a certain dose of anthelmintic drugs (AH) in eliminating the presence of a parasite population that was previously susceptible. The main aim of this study is to examine anthelmintic resistance in domestic herbivores. There are numerous factors playing a role in the development of AR, but the most important is livestock management. The price of AH and the need to treat a high number of animals mean that farmers face significant costs in this regard, yet, since 1981, little progress has been made in the discovery of new molecules and the time and cost required to bring a new AH to market has increased dramatically in recent decades. Furthermore, resistance has also emerged for new AH, such as monepantel or derquantel. Consequently, ruminant parasitism cannot be controlled solely by using synthetic chemicals. A change in approach is needed, using a range of preventive measures in order to achieve a sustainable control programme. The use of nematophagous fungi or of plant extracts rich in compounds with anthelmintic properties, such as terpenes, condensed tannins, or flavonoids, represent potential alternatives. Nevertheless, although new approaches are showing promising results, there is still much to do. More research focused on the control of AR is needed.

First confirmed record of Mola sp. A in the western Mediterranean Sea: morphological, molecular and parasitological findings.

Recent molecular and morphological studies suggest the existence of at least three species of Mola (Mola spp. A, B and C). Currently, only Mola mola and Mola ramsayi are formally accepted and species A, B or C have not been assigned to these thus far. In this study, a large ocean sunfish in the western Mediterranean Sea was analysed molecularly and morphologically, identified as Mola sp. A and a detailed account of the specimen's parasite load is reported.

Angular roughshark Oxynotus centrina (Squaliformes: Oxynotidae) in captivity feeding exclusively on elasmobranch eggs: an overlooked feeding niche or a matter of individual taste?

A specimen of angular roughshark Oxynotus centrina has been kept successfully in captivity for the first time. Over a period of 24 months, the specimen preyed exclusively on the contents of elasmobranch egg cases, suggesting a specialized trophic niche.

Morphometric, molecular and ecological analyses of the parasites of the sharpsnout seabream Diplodus puntazzo Cetti (Sparidae) from the Spanish Mediterranean: implications for aquaculture.

One of the fish species with the highest potential for aquaculture is the sharpsnout seabream, Diplodus puntazzo Cetti. Among other aspects, the development of new fish cultures requires studies of potential pathogens that may compromise survival of the fish in captivity. Moreover, both cultured and wild fish can act as sources or reservoirs of pathogens which may negatively affect other well-established cultures. We have studied the parasite fauna of the wild sharpsnout seabream, and monitored the survival of the parasites in culture conditions. The sharpsnout seabream was sampled from two different Spanish localities and examined for parasites. Additionally, 20 fish were maintained in captivity. Ten of them were examined for parasites after a period of 10 days and a further ten fish after another 10 days. All fish were parasitized with at least four species, with 19 parasite species being identified, seven of which were recorded for the first time in the sharpsnout seabream. These included Microcotyle sp., Magnibursatus bartolii, Steringotrema pagelli, Galactosomum sp., Cardiocephaloides longicollis, Caligus ligusticus and Gnathia vorax. We also report the first records of two parasite species in the wild sharpsnout seabream, the polyopisthocotylean monogeneans Atrispinum seminalis and Sparicotyle chrysophrii. Previously, these parasites had only been recorded in farmed sharpsnout seabream. Most parasites in the skin, gills and alimentary tract disappeared under the conditions of captivity, with the exception of the monogeneans of the genus Lamellodiscus. The information provided about the sharpsnout seabream parasite fauna will be useful to prevent possible problems in fish farms due to some parasite species. Many parasites of the sharpsnout seabream recorded in the present study are shared by the main fish species in Mediterranean aquaculture, the gilthead seabream, thus suggesting the possibility of cross-infections.

Molecular and morphological differentiation of two similar species of Accacoeliidae (Digenea): Accacladocoelium macrocotyle and A. nigroflavum from sunfish, Mola mola.

In a study of 106 sunfish, Mola mola (L.), from Mediterranean waters, 2,731 worms, belonging to 2 congeneric species of accacoeliids, Accacladocoelium macrocotyle (Diesing, 1858) Robinson, 1934 and Accacladocoelium nigroflavum (Rudolphi, 1819) Robinson, 1934 , were collected from the digestive system. It is often difficult to differentiate between these 2 species as they are sympatric and very similar; in fact, according to previous descriptions, the extent of the vitellarium is the only interspecific difference, described as extending posteriorly to the ovary in A. macrocotyle and as anterior to the anterior testis in A. nigroflavum. However, this diagnostic trait is not always valid; moreover, it is often indistinguishable because it is masked by the uterine eggs. Here, the morphology of new specimens of both species has been studied in detail and combined with molecular analysis. This study shows that the extension of the vitellarium is very similar in both species, but the degree of ramification differs. Furthermore, although the morphological differences are very slight, both species seemed genetically different: intraspecific differences ranged between 0.8 and 1.5% in internal transcribed spacer (ITS)-2 rRNA gene (ITS2) and between 0.5 and 1.6% in cytochrome c oxidase subunit 1 (COI) and interspecific differences ranged between 2 and 3.2% in ITS2 and between 9.6 and 10.6% in COI. In addition, we observed previously undescribed morphological differences, which help to differentiate these 2 species: the oral sucker is relatively smaller in A. nigroflavum than in A. macrocotyle and the ovary is usually relatively longer in A. nigroflavum than in A. macrocotyle.