Review highlights gaps in livestock myokine research
Bottom line
Physical activity may shape livestock muscle signaling, but the evidence base is still thin. In a mini-review published June 15 in Frontiers in Veterinary Science, Annika Krause and colleagues identified 35 studies on physical activity-induced myokine responses in pigs, cattle, sheep, and goats, covering markers including IL-6, irisin/FNDC5, BDNF, myostatin, and IGF-1. The authors found the literature is highly heterogeneous, with most studies not designed specifically to test exercise-driven myokine biology, and they argue that farm animal research needs more standardized, objective ways to measure activity before stronger conclusions can be drawn. (frontiersin.org)
Why it matters: For veterinary professionals working in farm animal health and welfare, the review connects a familiar management question, how much animals move, with emerging biology around muscle-derived signaling and whole-animal health. The paper suggests physical activity could influence not just muscle development and performance, but also welfare-relevant outcomes, while underscoring that current evidence is too fragmented to guide practice confidently. That gap is especially important because commercial and research settings increasingly have access to accelerometers and other sensor tools that can capture activity more objectively than housing type or enrichment alone. (frontiersin.org)
What to watch: Expect the next phase of work to focus on sensor-based activity tracking paired with muscle and blood biomarker sampling in commercial livestock systems. (frontiersin.org)
Key facts
- Article type
- Mini-review
- Journal
- Frontiers in Veterinary Science
- Publication date
- June 15
- Authors
- Annika Krause and colleagues
- Studies reviewed
- 35
- Species covered
- Pigs, cattle, sheep, and goats
- Markers examined
- IL-6, irisin/FNDC5, BDNF, myostatin, and IGF-1
- Main limitation
- Highly heterogeneous methods; most studies were not designed to test exercise-driven myokine biology
- Research need
- More standardized, objective activity measurement, including sensor-based tracking
A new mini-review in Frontiers in Veterinary Science argues that livestock myokine research is still at an early stage, despite growing interest in how movement may affect muscle biology, health, and welfare in farm animals. Published June 15, the paper by Annika Krause and colleagues reviewed the evidence on physical activity-induced myokine responses in major mammalian farm species and concluded that the field has more signals than answers so far. (frontiersin.org)
The backdrop is a broader shift in animal science toward understanding physical activity as more than simple locomotion. The review notes that farm animals are often housed in systems with limited opportunity for species-appropriate movement, even though locomotion is fundamental to skeletal muscle development and overall welfare. In human and laboratory animal research, contracting muscle is known to release myokines that shape interorgan signaling, metabolism, and other physiologic responses. In livestock, though, that framework is still being built. (frontiersin.org)
Using a literature search conducted in April 2026 across PubMed, Scopus, and Web of Science, the authors narrowed 1,247 records to 35 included studies. Most involved pigs, followed by cattle, with only two studies each in sheep and goats. The reviewed papers examined IL-6, FNDC5/irisin, BDNF, myostatin, and IGF-1, but the methods varied widely: some used treadmill or forced walking models, while others inferred greater activity from housing conditions, space allowance, or environmental enrichment. Only a small subset measured outcomes directly in skeletal muscle, the main tissue of interest for true myokine biology. (frontiersin.org)
That inconsistency is the paper’s central message. The authors say many studies were actually designed around nutrition, metabolism, reproduction, rehabilitation, or welfare, rather than exercise biology itself. As a result, it’s difficult to tell whether observed changes in BDNF, IGF-1, IL-6, or myostatin pathways were driven by movement, by the environment, by handling, or by other physiologic stressors. The review points to one example in pigs where enrichment was associated with higher serum BDNF, but activity itself was not objectively quantified, limiting interpretation. (frontiersin.org)
Outside this paper, the push for objective activity measurement is consistent with the wider precision livestock literature. Reviews of accelerometer-based monitoring and other wearable or sensor systems have found that activity data can support behavior classification, welfare assessment, estrus detection, and earlier identification of health problems in cattle and pigs. Those tools don’t solve the biology question on their own, but they do offer a practical path toward the kind of standardized exposure measurement this review says is missing. (sciencedirect.com)
No clear outside expert commentary on this specific review was readily available at publication, but the article’s framing aligns with a broader industry and research trend: welfare and productivity questions are increasingly being linked to continuous, animal-level monitoring rather than coarse management proxies. That’s an inference based on the sensor and welfare review literature, not a direct reaction to this paper. (pmc.ncbi.nlm.nih.gov)
Why it matters: For veterinarians and allied professionals in farm animal practice, the review is less about an immediate clinical takeaway and more about where evidence may be heading. If future studies can reliably connect movement patterns with myokine responses, that could sharpen understanding of how housing, enrichment, exercise opportunity, and recovery protocols affect muscle health, resilience, production traits, and welfare. It could also help distinguish beneficial activity from stress-associated physiologic change, an important line for both herd management and research design. (frontiersin.org)
What to watch: The next important step will be prospective studies that combine validated sensor-based activity tracking with repeated sampling of muscle and circulating biomarkers in commercial pigs, cattle, sheep, and goats, ideally using common definitions of activity intensity and duration. Until then, this review positions the field as promising, but methodologically immature. (frontiersin.org)