Red Algae Asparagopsis taxiformis as a Feed Additive for Parasite Prevention in Organic Pasture Raised Sheep

Project Overview

Project Type: Farmer
Funds awarded in 2020: $15,000.00
Projected End Date: 03/31/2022
Grant Recipient: Zfarms
Region: Northeast
State: New York
Project Leader:


  • Animals: sheep
  • Animal Products: meat


  • Animal Production: animal protection and health, feed additives, feed formulation, feed management, feed rations, herbal medicines, meat product quality/safety, parasite control, preventive practices, probiotics, therapeutics
  • Education and Training: farmer to farmer, on-farm/ranch research, technical assistance, workshop
  • Energy: byproduct utilization, energy conservation/efficiency
  • Production Systems: organic agriculture
  • Soil Management: nutrient mineralization, organic matter, soil analysis

    Proposal summary:

     Asparagopsis taxiformis, a species of red marine macroalgae,  has been shown to reduce methane (CH4) production in the rumen of dairy cattle by over 80% in recent  studies. The particular components of the seaweed change the rumen microbiome and reduce bacterial fermentation and CH4 production without diminishing fatty acid production. Due to previous research regarding its antibacterial and anti parasite properties, it is possible that Asparagopsis taxiformis changes not only rumen but intestinal microbiome of pasture raised animals with resulting positive effects on immune function and parasite resistance.  
    We suggest running a field trial with two groups of animals (1) a feed supplemented study group to include 20 sheep with 0.5% of feed ration as a red algae feed additive in addition to fresh pasture grass (mixed grasses plus legumes) for a period of 2 months and (2) a control group of 20 sheep regularly managed on pasture without red algae supplementation. We would collect stool samples for  intestinal microbiome composition - whole metagenome sequencing data, taxonomic profiling, estimation of alpha and beta diversity, fecal egg counts with flotation method at 0, 3 weeks and 6 weeks. Also animals will be  checked  for  clinical signs and symptoms of  parasite infestation,FARMACHA  and total body  health scoring.  We would compare microbial communities in two groups based on taxonomic profiling of metagenomic data, as well as parasite infestation counts. The results would help to answer question whether Asparagopsis taxiformis can help improve animal health, gut microbiome and parasite resistance in addition to reducing methane emission and helping alleviate the greenhouse effect. 

    Project objectives from proposal:

    The project will try to find an answer if an addition  of red seaweed Asparagopsis taxiformis 0.5% of organic matter to feed of pasture raised organic sheep would help integrative parasite control,  body score composition and microbial diversity of the colon.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.