Pumpkin seed oil shows mixed results in weaned lamb study

A newly published study in Veterinary Sciences examined whether oral pumpkin seed oil could support health in weaned Pırlak lambs, a period when animals face nutritional transition and oxidative stress. The answer was mixed: daily supplementation for 45 days did not improve body weight gain, but it was associated with selective shifts in oxidative status, HDL cholesterol, and serum IgG patterns, with no consistent evidence of hepatic or renal harm in the measured bloodwork. (mdpi.com)

The work arrives as interest grows in plant-derived nutritional additives for young ruminants, especially around weaning, when lambs may experience immune and antioxidant strain. Previous literature has described weaning as a biologically stressful phase for lambs, and recent nutrition studies in the species have explored whether by-products or plant bioactives can improve antioxidant defenses or inflammatory tone. That broader context helps explain why pumpkin seed oil, which is rich in polyunsaturated fatty acids and other bioactive compounds, is drawing attention as a possible functional supplement. (frontiersin.org)

In the new trial, investigators enrolled 45 clinically healthy weaned male Pırlak lambs with a mean initial age of about 120 days and mean body weight of roughly 37.6 kg. Animals were assigned to a control group or to pumpkin seed oil at 0.5 mL/kg or 1 mL/kg body weight, administered by oral gavage once daily for 45 days. Blood sampling was performed at baseline and on days 15, 30, and 45. According to the paper, supplementation did not significantly affect body weight gain or serum growth hormone concentrations. However, total oxidant status was lower in both supplemented groups than in controls on day 30, and the oxidative stress index was lower in the 1 mL/kg group on day 45. HDL cholesterol increased over time, particularly in the higher-dose group, while LDL did not change significantly. Serum glucose also declined over time, and the authors did not find consistent dose-dependent adverse changes in liver or kidney function indicators. (mdpi.com)

One of the more eye-catching findings was the higher serum IgG concentration in supplemented lambs, but that result comes with an important caveat the authors themselves emphasized: the between-group differences were already present on day 0. In other words, the study cannot cleanly attribute the IgG pattern to pumpkin seed oil supplementation alone. That limitation matters because it keeps the immune story from becoming stronger than the data support. It also reinforces that this was an exploratory nutrition study, not a definitive demonstration of immune enhancement. (mdpi.com)

Direct outside commentary on this specific paper was limited at the time of writing, but the broader research landscape supports a measured interpretation. Other lamb studies have shown that plant-based supplements can alter antioxidant or inflammatory biomarkers, yet those changes do not always produce better growth or clearer clinical benefits. Older work on pumpkin seed products in lambs and kids, for example, found little effect on body weight and did not demonstrate meaningful antiparasitic benefit under the tested conditions. Together, that suggests pumpkin-derived products may have biologic activity, but the route, dose, target outcome, and production setting likely matter a great deal. (frontiersin.org)

Why it matters: For veterinarians, nutritionists, and sheep producers, this study is useful less as a practice-changing result and more as an early signal. It suggests pumpkin seed oil may influence redox balance and lipid metabolism in weaned lambs without obvious short-term safety flags in standard serum chemistry. But because the study was small, used oral gavage rather than routine feed inclusion, and did not improve growth performance, it doesn’t yet support broad clinical or production recommendations. Veterinary professionals advising pet parents with hobby flocks or commercial sheep operations should view this as hypothesis-generating evidence, not a ready-made supplementation protocol. (mdpi.com)

There’s also a translational point for herd-health management: biomarker improvements are only valuable if they ultimately connect to outcomes that matter in practice, such as feed efficiency, resilience during weaning, lower morbidity, or improved response to environmental and infectious stressors. The current paper did not establish those downstream benefits. That leaves an open question about whether the observed oxidative and lipid effects are biologically meaningful enough to justify cost, labor, and formulation work in real-world lamb programs. (mdpi.com)

What to watch: The next step is likely larger and longer-duration trials that test pumpkin seed oil in practical feeding systems, include better-balanced baseline groups, and measure production and health endpoints beyond serum biomarkers, especially through the post-weaning risk window. (mdpi.com)