Fukuda Emma P, Cox Jodi R, Wickersham Tryon A, Drewery Merritt L
Department of Agricultural Sciences, Texas State University, San Marcos, TX 78666, USA.
Department of Animal Science, Texas A&M University, College Station, TX 77843, USA.
Transl Anim Sci. 2022 Jan 25;6(1):txac018. doi: 10.1093/tas/txac018. eCollection 2022 Jan.
Black Soldier Fly larvae (BSFL; ) has been the focus of recent feeding trials in poultry, swine, and fish; however, in vivo research has not yet been conducted in cattle. Accordingly, a study was conducted to evaluate the effects of BSFL as a protein supplement in beef steers. Six steers (603 ± 20 kg of BW, = 3 and 404 ± 17 kg of BW, = 3) consuming King Ranch bluestem hay (6.55% dry matter [DM] crude protein [CP]) ad libitum were used in two simultaneous 3 × 3 Latin squares. Steers were provided one of three treatments each period: 1) a control with no supplement (CON), 2) a supplement comprised of conventional feed ingredients with whole cottonseed and soybean meal as the main protein sources (CONV), and 3) a supplement with BSFL as the main protein source (BSFL). Three 14-d periods were conducted with 8 d to adapt to treatments, 5 d to measure intake and digestion, and 1 d to complete a ruminal fermentation profile. DM, organic matter (OM), CP, neutral detergent fiber (NDF), and acid detergent insoluble ash were determined in forage, supplement, ort, and fecal samples. Protein supplementation as CONV or BSFL stimulated forage OM intake ( ≤ 0.01) relative to CON with a trend for a difference ( = 0.08) between the supplements such that CONV steers consumed more FOMI than BSFL steers. Treatment affected total digestible OM intake (TDOMI; ≤ 0.01); TDOMI for CON steers was 47.5 g/kg metabolic body weight (MBW) which was significantly less ( ≤ 0.01) than that of CONV or BSFL steers. Steers supplemented with CONV consumed significantly more TDOMI than BSFL steers ( 0.05; 62.2 vs. 60.1 g/kg MBW, respectively). Treatment did not significantly affect digestibility of DM, OM, or NDF ( 0.32). There was also not a significant effect ( ≥ 0.17) of treatment on ruminal ammonia-N, total volatile fatty acids, or ruminal pH. Overall, these data indicate that BSFL may be an effective protein supplement for beef cattle consuming low-quality forage.
黑水虻幼虫（BSFL）一直是近期家禽、猪和鱼类饲养试验的焦点；然而，尚未在牛身上进行体内研究。因此，开展了一项研究以评估BSFL作为肉牛蛋白质补充剂的效果。在两个同步的3×3拉丁方试验中，使用了6头体重603±20千克（n = 3）和404±17千克（n = 3）的肉牛，它们随意采食金牧场蓝茎草干草（干物质[DM]粗蛋白[CP]含量为6.55%）。每个时期给肉牛提供三种处理之一：1）不添加补充剂的对照处理（CON）；2）以全棉籽和豆粕作为主要蛋白质来源的传统饲料成分组成的补充剂（CONV）；3）以BSFL作为主要蛋白质来源的补充剂（BSFL）。试验进行了三个14天的周期，其中8天用于适应处理，5天用于测量采食量和消化率，1天用于完成瘤胃发酵特征分析。测定了饲料、补充剂、剩余饲料和粪便样本中的干物质、有机物（OM）、粗蛋白、中性洗涤纤维（NDF）和酸性洗涤不溶性灰分。与CON相比，CONV或BSFL补充蛋白质刺激了牧草有机物采食量（P≤0.01），两种补充剂之间存在差异趋势（P = 0.08），使得CONV组肉牛比BSFL组肉牛消耗更多的牧草有机物采食量（FOMI）。处理影响了总可消化有机物采食量（TDOMI；P≤0.01）；CON组肉牛的TDOMI为47.5克/千克代谢体重（MBW），显著低于（P≤0.01）CONV组或BSFL组肉牛。补充CONV的肉牛消耗的TDOMI显著多于BSFL组肉牛（P＜0.05；分别为62.2和60.1克/千克MBW）。处理对干物质、有机物或中性洗涤纤维的消化率没有显著影响（P≥0.32）。处理对瘤胃氨氮、总挥发性脂肪酸或瘤胃pH值也没有显著影响（P≥0.17）。总体而言，这些数据表明，BSFL可能是食用低质量牧草的肉牛的一种有效蛋白质补充剂。
