Medicated Urea molasses blocks for controlling internal parasites

The blocks containing fenbendazole, albendazole or levamisole reduce faecal egg counts by > 90%, pineapple leaf by 80–90%.
The cost:benefit ratios for using medicated blocks ranged from 1:1.3 to 1:7.8 across the different countries and increased farmer income per animal by 33–445%.

Helminthiasis is a common problem in grazing animals, particularly in domestic ruminants. Haemoncus contortus as an example is causing anaemia and hypoproteinaemia and as a result reduced body condition. Other common nematodes include Trichostrongylus and Oesophagostomum species, both damaging the intestinal epithelium and causing leakage into the gastrointestinal tract. These parasites cause heavy mortality in young animals and production losses in adults. The conventional way to medicate animals for helminthiasis is oral drenching with anthelmintics several times a year, but the animals can become stressed during handling. Additionally overdosing can lead the very quick destruction of the parasites leading to intoxication of the host.

Sheep and cattle receiving multi-nutrient urea-molasses blocks in the field Multi-nutrient urea-molasses blocks are used as a feed supplement for ruminants in areas where feed is often sparse and of poor quality.  It is possible that these blocks could also be a convenient vehicle for delivering anthelmintics. Under an IAEA Regional Asia Project (RAS/5/035) and with the technical support from the Joint FAO/IAEA Division, studies have been carried out in Bangladesh, China, India, Indonesia, Malaysia, Mongolia, Myanmar, Pakistan, Sri Lanka, Thailand, Vietnam, on the development and use of medicated blocks for controlling helminth parasitism.

Medicated blocks containing fenbendazole, albendazole or levamisole were prepared. Herbal anthelmintics, such as Pineapple leaves, Momordica charantina, Neem, Anona squamosa, Stellaria chameajasmae, Curcuma aeroginosa, and Kenaf have also been tested. Ninety-one farms were involved in evaluations of these blocks using 833 cattle, buffalo, goats and sheep.

The results are promising. The blocks containing fenbendazole, albendazole or levamisole were highly effectively in reducing faecal egg counts (> 90% reduction). Pineapple leaf effectively reduced faecal egg count by 80–90%. Momordica, Cucurma, Stellaria, Anona, Kenaf and Neem leaves all showed anthelmintic activity ranging from a 44 to 90% reduction in faecal egg count .Effective worm control increased live-weight gain by up to 500% in young beef cattle and 80% in sheep. In Malaysia, effective worm control decreased mortality to zero and increased reproductive rate by 300%.

The cost:benefit ratios for using medicated blocks ranged from 1:1.3 to 1:7.8 across the different countries and increased farmer income per animal by 33–445%.

Table 1. Impact of feeding multinutrient blocks medicated with commercially available and herbal anthelmintics

  Benefit/cost Increase in income (/cow/day) % Increase in income (/cow/day)
Bangladesh 3.0–5.1 Milk - 16 Taka/day 33%
Indonesia 1.4–1.7 Milk - 1500–5300 Rupiah/day 17%
Malaysia 7.8 Meat - 312 Ringgit (total) 445%
Thailand 1.3 Milk - 12 Baht/day 1%
Vietnam 5.1% Fenbendazole
2.8% Pineapple
Dairy - Fenbendazole 4700 Dong/day
Beef - Pineapple 9760 Dong/day
147%
121%

Six countries have extended the use of medicated blocks to more than 800 farmers, using either fenbendazole or pineapple leaves as the anthelmintic. The low cost of herbal remedies made this a preferred option in Myanmar, Bangladesh and Vietnam. However, in China, Pakistan and Sri Lanka, it was cheaper to use conventional applications and was not accepted by farmers.

The technology is attractive, but its exploitation will depend on the ability to manufacture medicated blocks at an industrial scale at a cost that is competitive with the conventional applications using commercial products.