Anthelmintic effects of condensed tannins on Trichostrongylus colubriformis in experimentally infected sheep

Abstract

Recent surveys have identified anthelmintic effects from many bioactive substances particularly from condensed tannin (CT) sources. The aims of the present study were to investigate the potential anthelmintic effects of condensed tannins (CT) on Trichostrongylus colubriformis in experimentally infected sheep and the nutritional consequences on animals. Twenty helminth-free lambs were divided into five groups of four animals. Groups I to IV were artificially infected with 6,000 third stage larvae (L3) of T. colubriformis. Group I was the infected control and group V was the uninfected control. Twenty-eight days post-infection (p.i.) lambs from GII were supplemented with tanniniferous sorghum (350 g/animal/day, during seven days); GIII were drenched with Acacia mearnsii extract (15% CT) for just one day and GIV during two days (1.6 g extract/kg BW). At day 36 p.i., animals from infected group (GI to GIV) were slaughtered. Faecal egg counts (FEC) values present a reduction on GII when compared with GI at day 29 p.i. (P < 0.05) and between GIII and GI at day 35 and 36 p.i. (P < 0.05). The values of egg hatchability and number of L3 recovered from the faeces were not statistical analyzed (there was no duplicate data), however there was a considerable reduction between the values from treated and control group. The use of CT on diet did not cause significant difference on blood parameters, body-weight and carcass-weight (P > 0.05). No difference was related on total worm burden between treatments; however, GIV presented lower number of females than GI (P < 0.05). The use of CT could be a promising alternative source to reduce the pasture contamination and to control T. colubriformis infection in sheep. Key words: Nematode, ovine, alternative control, bioactive compounds, tannins ResumoO objetivo principal deste trabalho foi avaliar o potencial efeito anti-helmíntico dos taninos condensados sobre Trichostrongylus colubriformis em ovinos experimentalmente infectados e as conseqüências nutricionais destes produtos sobre os animais. Vinte ovinos livres de infecção parasitária foram divididos em cinco grupos de quatro animais. Os grupos GI a GIV foram experimentalmente infectados com 6000 larvas infectantes (L3) de T. colubriformis. O GI foi mantido como controle infectado e o GV como controle não infectado. Vinte e oito dias pós-infecção (p.i.) os animais foram tratados com fontes de taninos condensados (TC): o GII suplementado com 350 g de sorgo taninífero, durante sete dias; os 1 Pesquisador. Instituto Agronômico do Paraná, IAPAR, Rod. Celso Garcia Cid, km 375, C.P.

Use of agro-industrial by-products containing tannins for the integrated control of gastrointestinal nematodes in ruminants

“…Intake of A. mearnsii bark in feed by sheep and goats reduced the GIN FEC [18,27,73]. Also, it reduced egg viability and consequently the quantity of L3 from eggs collected from animals fed with A. mearnsii bark extract [74]. These results indicate the potential of feeding such tannins to reduce infective larvae on the pasture and, consequently, animal reinfection.…”

“…adults were reduced in sheep that received A. mearnsii bark extracts [18], but they did not reduce H. contortus, T. colubriformis, and Oesophagostomum columbianum adult worms in goats [27]. It has also been shown that the use of A. mearnsii bark did not alter blood parameters or carcass measurements of sheep and goats naturally or experimentally infected with nematodes [18,27,73,74].…”

Biological Function of Plant Tannin and Its Application in Animal Health

“…In vitro bioassays evaluated the effects of condensed tannins (CTs) obtained from Lotus pedunculatus (LP), Lotus corniculatus (LC), Dorycnium pentaphyllum (DP), Dorycnium rectum (DR), and Rumex obtusifolius (RO) on egg hatching, larval development and the viability of Teladorsagia circumcincta (Stadelmann, 1894) (Ostertagia circumcincta) and the L3 larvae of Trichostrongylus colubriformis (Giles, 1892). These studies showed that CTs were able to inhibit egg hatching, slow larval development, kill undeveloped larvae and disrupt the life cycle of nematodes (60)(61)(62). Some experiments evaluated the anthelmintic effects of extracts from tropical tanniniferous plants (TTPs), such as Acacia pennatula, Lysiloma latisiliquum, Piscidia piscipula and Leucaena leucocephala, on Haemonchus contortus.…”

Procyanidins in Lotus L. genotypes grown in soil with different saturations of aluminum

“…When the leaves, stems, and flowers consumed by the animals are disintegrated by chewing, CTs are released; they react and form complex soluble proteins and prevent the formation of foam in the rumen (BARRY, 1983). The levels of 2-4 % of CTs have been estimated to be required for the prevention of this nutritional disorder; further, CTs increase protein absorption in the small intestine and abomasum, which increases lactation, improves wool production and weight gain in sheep (WAGHORN et al, 1987(WAGHORN et al, , 1998MOLAN et al, 1999), and promotes animal health by acting on gastrointestinal parasites (MINHO et al, 2010;YOSHIHARA et al, 2014).…”