|STEWART, W - Texas A&M Agrilife|
|WHITNEY, R - Texas A&M Agrilife|
|SCHOLLJEGERDES, E - New Mexico State University|
|NAUMANN, H - University Of Missouri|
|CHERRY, N - Texas A&M Agrilife|
|MUIR, J - Texas A&M Agrilife|
|LAMBERT, B - Texas A&M Agrilife|
|WALKER, J - Texas A&M Agrilife|
|ADAMS, R - Baylor University|
|Estell, Richard - Rick|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/11/2015
Publication Date: 8/6/2015
Publication URL: http://handle.nal.usda.gov/10113/62997
Citation: Stewart, W.C., Whitney, R.R., Scholljegerdes, E.J., Naumann, H.D., Cherry, N.M., Muir, J.P., Lambert, B.T., Walker, J.W., Adams, R.P., Welch, K.D., Gardner, D.R., Estell, R.E. 2015. Effects of juniperus species and stage of maturity on nutritional, in vitro digestibility, and plant secondary compound characteristics. Journal of Animal Science. 93(8):4034-4047.
Interpretive Summary: Rising feed costs and recurring feed shortages necessitate the investigation of alternative feed ingredients. Woody plants from the genus Juniperus have worldwide distributions and cover over 50 million ha in the western United States. Leaves and small stems of these increasingly abundant plants can be used as a roughage ingredient in mixed diets for ruminant livestock. However, secondary compounds such as volatile oil and condensed tannins present in Juniperus species can either positively or negatively affect animal performance and rumen function. The objective of this study was to quantify nutritional, in vitro digestibility, and plant secondary compound characteristics of J. pinchotii, Juniperus monosperma, Juniperus ashei, and J. virginiana at mature and immature growth stages to assess their suitability as a feed ingredient. Findings indicate the nutritional and in vitro digestibility of ground whole immature and mature juniper trees for the 4 juniper species studied were equal to or better than other commonly used and approved roughage sources. Concentrations of plant secondary compounds when juniper is dried, ground, and mixed with other feed ingredients should cause no adverse effects to ruminants and could provide some health benefits. The study overall indicates that Juniperus species can be used as a roughage source in ruminant diets.
Technical Abstract: Rising feed costs and recurring feed shortages necessitate the investigation into alternative and underutilized feed resources. Nutritional characteristics of species are either unknown or limited to leaves and ground material from small stems. Therefore, the objective was to quantify nutritional characteristics, 48-h true IVDMD (tIVDMD), microbial gas production, and secondary compound characteristics of entire woody plant material of 4 species-, , , and -at immature and mature stages of growth. Immature plants had greater CP concentrations and lower NDF concentrations ( < 0.001) than mature plants regardless of species. Mature plants also had greater ( < 0.001) concentrations of ADF compared with immature plants with the exception of . In general, immature , , and had greater ( < 0.02) tIVDMD and total 48-h and asymptotic gas production than mature plants. Immature and plants were more digested (tIVDMD; < 0.001) than immature and , but tIVDMD did not differ in mature plant material across species. Condensed tannins (CT) were greater ( < 0.001) in immature and than mature plants; differences in CT concentrations among immature species were also detected ( < 0.04). Volatile oil yields were similar across maturity and species with 1 exception: immature yielded more ( < 0.02) volatile oil than mature material. Volatile oil composition across species varied and contained a range of 65 to 70 terpene compounds. The dominant terpenes across species were generally greater ( < 0.05) in immature vs. mature plant material with the exception of . Labdane acids were negligible in , , and and greater in ( < 0.001). Ground material from mature juniper species, although inferior in nutritional quality compared with immature plants, is comparable to traditional low-quality roughage ingredients. Given that has been successfully fed in lamb feedlot diets, the similarities of , and suggest that all three species have potential to be effective roughage ingredients.