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Performance and Reproductive Measurements of Katahdin Ewes and Fall-Calving Angus Cows Grazing Stockpiled Toxic Tall Fescue Under a Mixed or Sequential Grazing Scheme – 2 Year Summary
Multi-species grazing has several potential advantages and ultimately may improve performance for one or both species. With renewed interest in multi-species grazing, there is value in evaluating mixed versus sequential grazing schemes. However, there has been little research evaluating hair sheep and cattle grazing stockpiled toxic tall fescue (E+) either mixed or sequentially. Our objectives were to determine performance and reproductive measurements of Katahdin ewes and fall-calving Angus cows grazing stockpiled E+ under a mixed or sequential grazing scheme. Katahdin ewes (n = 81; 27 ± 3.6 kg initial BW; 3 ± 0.07 initial BCS) and fall-calving Angus cows (n = 40; 471 ± 23.5 kg initial BW; 6 ± 0.6 initial BCS) were stratified by BW and age within species and were allocated randomly to 1 of 4 groups representing 2 treatments: 1) mixed grazing (4 replications) or 2) sequential grazing (4 replications). In the sequential grazing treatment, cows always followed ewes. Each group had access to a 0.68-ha paddock and were rotated based on available forage. A total of 8.16 ha were grazed over 40 d for all groups. Initial weight and BCS from ewes and cows did not differ (P ≥ 0.83) across treatments. Average daily gain, total gain, end weight, and end BCS from ewes and cows did not differ (P ≥ 0.35) across treatments. Cow pregnancy rate, calf birth date, and calf birth weight did not differ (P ≥ 0.56) across treatments. Calf start weight, end weight, average daily gain, and total gain did not differ (P ≥ 0.26) across treatments. Ewe pregnancy rate, lamb birth date, and lamb counts did not differ (P ≥ 0.11) across treatments. A treatment × sex interaction tendency (P = 0.06) was detected for lamb birth weight and a treatment × sex interaction (P = 0.01) was detected for lamb weaning weight. Mixed grazing ram lambs tended to be heavier at birth compared with mixed grazing ewe lambs, and mixed grazing ram lambs were heavier compared with sequentially grazed ram lambs at weaning. Therefore, utilizing sequential grazing with Katahdin ewes and fall-calving Angus cows may not increase performance or reproductive measurements; thus, managing a multi-species, sequential grazing regime relative to mixed grazing may not be warranted.
Keywords:
Fescue, Mixed grazing, Sequential grazing