Limited role of lagomorphs (Oryctolagus cuniculus and Lepus capensis) in the dispersion of parasite nematodes of ruminants

Nutritive value and anthelmintic effect of sainfoin pellets fed to experimentally infected growing rabbits

Alternative strategies to synthetic chemical drugs are needed in livestock and are a key issue in organic farming today. This study aimed at examining the potentialities of sainfoin, a legume rich in condensed tannins, as a nutraceutical that combines nutritive and antiparasitic effects in rabbits. To test the effect of infection with a helminth (I: infected groups; NI: not infected groups) and the effect of substituting 40% of the alfalfa in a control diet (C) with sainfoin (diet S), four groups of 16 weaned rabbits were arranged according to a 2×2 bifactorial design. The sainfoin diet differed from the control by its tannin concentration (1.8% v. 1.0% tannic acid equivalent) and its ADL concentration (84 v. 43 g/kg). For each diet, 16 rabbits were infected with 2125 third-stage larvae of Trichostrongylus colubriformis. Growth, feed intake, feed conversion ratio and nematode faecal egg counts (FECs) were controlled for 6 weeks. A digestibility trial was performed. After necropsy, adult worms and eggs in utero per female were counted and egg-hatching rate calculated. Growth tended to be lower for S groups than for C groups (38.2 v. 39.5 g/day; P=0.06). Feed intake was higher for S groups compared with C groups (+5.2 g dry matter/day; P<0.01), as was the feed conversion ratio (3.2 v. 2.9; P<0.001), probably in relation to the dietary ADL level. Protein digestibility was reduced in S groups compared with C groups (-6.0 points; P<0.001), probably associated with the effect of the tannin concentration. Digestibility of hemicelluloses was reduced in infected rabbits compared with non-infected ones (-5 points; P=0.01). Using the substitution method, the digestible energy of dehydrated sainfoin pellets used as raw material was calculated at 11.12 MJ/kg and digestible proteins at 110 g/kg. The infection did not produce any clinical signs of digestive disorders. No differences were observed according to the diet, neither in the number of adult worms (972; P=0.50), the number of eggs in utero per female (14; P=0.95), nor FEC (400 eggs/g; P=0.57). In contrast, the rate of faecal egg hatching in the S group tended to be lower than in the control (58.3% v. 85.2%; P=0.08). In conclusion, sainfoin seems to fit nutritive requirements for rabbits, supplies a large quantity of fibre and particularly lignins, and limits the development of nematode eggs in faeces.

A rare case of verminous pneumonia in domestic rabbit

A 3-year-old female rabbit housed in 98 Mob Fd Vet Hospital/Farm at Charri, Himachal Pradesh, was found dead without showing any clinical signs. At necropsy, one foetus was recovered from the uterus of the animal. The histopathological examination showed presence of a very large number of ova and larvae of Protostrongylus sp. in the alveolar spaces in the lungs. Severe verminous pneumonia, a condition which is rarely reported in farm/domestic rabbit, led to the death of the animal.

Assessment of the gastrointestinal helminth fauna of mountain hares (Lepus timidus varronis) from the northwestern Italian Alps, with new records of parasite occurrence

We describe the gastrointestinal parasite community of Lepus timidus varronis, a subspecies of the mountain hare (L. timidus) living in the Alps. Two nematode species are reported for the first time in L. timidus.

First report of Obeliscoides cuniculi in European brown hare (Lepus europaeus)

Obeliscoides cuniculi is a New World nematode parasite of the Trichostrongilidae family infecting the gastric tract of different domestic and wild Lagomorph species. This parasite is reported for the first time from a European brown hare (Lepus europaeus). The nematodes isolated from the gastro-intestinal tract were identified using the primary characteristics used to differentiate the species of this genus as adults morphology (length and thickness) and other characteristics of spicules, cervical papillae, cuticular ridges and striations. In the Italian study area, the European brown hare lives in sympatry with the eastern cottontail (Sylvilagus floridanus), species in which the nematode was previously isolated; therefore, the possibility of a cross-infestation must be considered.

The experimental establishment of ruminant nematodes in European hares (Lepus europaeus)

The factors that control the demography of European hare Lepus europaeus populations are poorly understood, but it has been recognized that the decline of hares in Europe is associated with an increasing intensity of agricultural activity. Many mechanisms have been suggested. We propose another mechanism; a negative impact arising from ingestion of the infective larvae of ruminant livestock. We dosed juvenile hares from a worm-free colony with a conservative dose from a mixed culture of infective larvae of the nematode parasites of sheep and cattle. We examined the hares post-mortem for the establishment of those ruminant nematodes, differences in weight changes, and the shedding of eggs. We found that under the circumstances of our trial, Trichostrongylus colubriformis and to a lesser extent T. rugatus, T. vitrinus, and Teladorsagia circumcincta were able to establish as adults in the dosed animals. We found strongyle eggs in the faeces of the dosed hares, and were able to culture larvae from those eggs. However, the ecological significance of our findings, if any, remains to be elucidated. Because of their mobility, hares may transmit resistant strains of parasites between grazing properties.