Extended influence of colostral cells on mucosal responses to routine health challenges in neonatal lambs

    

Ruminant neonates rely on colostral immunoglobulin and nutrients to support health, welfare, and performance, by protecting against infectious disease and providing early life resilience. Recent evidence suggests that transferred colostral cells also contribute to neonatal immunity under controlled experimental conditions. This study provides evidence that colostral cells enhance neonatal resilience to routine, early-life, and mucosal health challenges in commercial lambs. A total of 78 lambs were tube-fed cell-rich (CRC, n = 39) or cell-free (CFC, n = 39) colostrum in 3 feedings within 12 h of birth. Lamb health was evaluated using body weight gain and natural disease incidence over time. Validated, observational scoring systems and thermal imaging were used to quantify peri-scrotal tissue swelling, skin temperature, and wound healing in male CRC (n = 13) and CFC (n = 16) lambs for 7 weeks post-castration. Fecal coccidial oocyst shedding was monitored in all lambs over 60 d of age, for 3 consecutive weeks. Statistical analysis employed a mixed linear model for intergroup effect, a repeated measure ANOVA for time effect, and Levene’s test for homogeneity and variability. The results showed that colostral cells significantly (P = 0.02) enhanced protection against coccidial infection in 63- to 70-d-old lambs and promoted a balanced inflammatory and healing response during the postcastration period, with CRC lambs exhibiting a significantly higher post-castration healing score at d 7 (P = 0.001), 35 (P = 0.002), and 42 (P = 0.03) and a lower post-castration swelling score at d 7 (P = 0.001), 28 (P = 0.04), and 35 (P = 0.017) compared with CFC lambs. This study shows that transferred colostral cells play an extended homeostatic role in intestinal mucosal health and in post-castration tissue inflammatory and healing responses. Although further research is needed to characterize the functional basis for these findings, the notion that colostral cells provide important benefits to neonatal health and welfare has significant implications for colostral management practices in livestock production systems.

Key Words: Colostrum, mucosal immunity, lambs, coccidia, healing.