Effect of maternal nutrition and regrouping on lamb behavior

Abstract Text:  A study was performed to measure the effects of uterine environment during gestation on regrouping on lamb behavior. Healthy twin and singleton lambs born to dams that received either a control (CON; n = 9) diet meeting NRC requirements or restricted (RES; n = 19) diet at 60% of NRC requirements.  Lambs were removed from dams and placed into 5 group pens.  At 38 ± 7 d of age, the lambs were blocked by treatment and randomly regrouped into new pens. Lamb behavior was recorded using a digital camera for 30 h across 3 d.  Each pen contained a raised platform (61 cm x 122 cm). Using the digital recordings, individual lamb behaviors were evaluated every 3 minutes and recorded.  Lambs spent more time ingesting creep feed on d 3 than on d 2 (P = 0.02) or d 1 (P = 0.03). Lambs spent more time lying alone at the end of the observation period than in the beginning (P < 0.01).  A treatment*day effect was present for time spent interacting with other lambs; those born to the RES dams decreased more in time spent interacting with other lambs than those lambs born to CON dams from d 1 to d 2 (P < 0.01) and from d 1 to d 3 (P = 0.01). All lambs significantly decreased the amount of time spent interacting with other lambs throughout the study (P < 0.01). Restricted lambs spent more time lying alone when compared to those born to CON.  Although amount of time spent interacting with the platform decreased with time for all lambs (P < 0.01), the proportion of time spent alone while interacting with the platform increased (P < 0.01).  In summary, creep feed intake and time spent alone increased in all lambs over time. Time spent alone was greater in lambs born to RES ewes than in those born to CON ewes. Adaptation over time after the stress of social regrouping was associated with increased feed intake, decreased time spent interacting with other lambs, and increased time spent lying alone. Lambs born to undernourished ewes spent more time alone and decreased time spent interacting with other lambs more quickly than lambs born to adequately fed ewes. The uterine environment during gestation may affect the ways that lambs interact with each other and their environment. 

Keywords: lamb, behavior, undernourishment