{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T23:50:51Z","timestamp":1773100251750,"version":"3.50.1"},"reference-count":33,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T00:00:00Z","timestamp":1677196800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>Evaluation of the effects of feeding NutraGen supplement (NutraGen, NTG; Phibro Animal Health, Teaneck, NJ, USA) on growth performance, energetic efficiency, carcass characteristcs, and characteristics of digestion in calf-fed Holstein steers fed a conventional growing-finishing diet. Trial 1 evaluated growth performance, dietary energetics and carcass characteristics. Two hundred Holstein steer calves (134 \u00b1 5 kg) were blocked by initial body weight (BW) and randomly assigned to 40 pens (5 steers\/pen). Dietary treatments consisted of a steam-flaked corn-based growing-finishing diet supplemented with 0, 0.2, 0.4, or 0.6% NTG (DM basis). In trial 2, four Holstein steers (170 \u00b16 kg) with cannulas in the rumen and proximal duodenum were used in a 4 \u00d7 4 Latin square experiment to evaluate digestibility and ruminal characteristics using the treatments from trial 1. Compared to non-supplemented cattle, NTG increased BW (2.0%, <jats:italic>P<\/jats:italic> = 0.02) and tended to increase ADG (3.6%, <jats:italic>P<\/jats:italic> = 0.07) during the initial 56 d period. However, there were no treatment effects on overall growth performance and efficiency of dietary energy utilization after the first 56 days (<jats:italic>P<\/jats:italic> &amp;gt; 0.10). Supplementation of NTG increased (linear effect; <jats:italic>P<\/jats:italic> \u2264 0.03) longissimus muscle area and kidney, pelvic, and heart fat. There was no effect (<jats:italic>P<\/jats:italic> \u2265 0.05) of NTG supplementation on other carcass characteristics, liver abscess incidence, or liver abscess scars. Supplementation decreased the molar proportion of ruminal propionate (<jats:italic>P<\/jats:italic> = 0.05) and tended to increase acetate:propionate molar ratio (<jats:italic>P<\/jats:italic> = 0.09). However, there was no effect of NTG supplementation on ruminal and total tract diet digestion. NTG increased performance of Holstein steers during the first 56 d on feed in the feedlot. In addition, the steers had an increase in KPH fat and LM area, indicating that the additive induced change in metabolism of the steers.<\/jats:p>","DOI":"10.3389\/fvets.2023.1039323","type":"journal-article","created":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T05:15:35Z","timestamp":1677215735000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["The effects of NutraGen supplement on cattle growth performance, energetic efficiency, carcass characteristics, and characteristics of digestion in calf-fed Holstein steers"],"prefix":"10.3389","volume":"10","author":[{"given":"Pedro H. V.","family":"Carvalho","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Brooke C.","family":"Latack","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcos V. 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