Casper David P, Scott Mark F
Casper's Calf Ranch LLC, Freeport, IL 61032; Department of Animal Sciences, North Carolina A & T State University, Greensboro, NC 27411.
Milk Specialties Global, Eden Prairie, MN 55344.
J Dairy Sci. 2025 Feb;108(2):1527-1537. doi: 10.3168/jds.2024-25509. Epub 2024 Dec 9.
Protein-encapsulated fat (PEF) blends are routinely used for manufacturing calf milk replacers (MR). The use of PEF blends improves fat mixability to ensure MR when mixed and fed as a homogeneous solution for neonatal calves. A new alternative PEF based on choice white grease (CWG) has been developed to improve its mixability and solubility to ensure a homogeneous MR solution. The alternative PEF is hypothesized to support similar growth performance (ADG, DMI, and feed efficiency) of neonatal calves and potentially reduce costs. The study objective was to evaluate CWG PEF as an alternative to a standard animal lard-tallow (ALT) PEF blend to mix a MR to be fed to Holstein calves. A total of 40 Holstein bull calves (2-5 d old) were blocked by BW and randomly assigned to 1 of 2 treatments (n = 20/treatment) using a randomized complete block design. The treatments were (1) CWG used to manufacture a PEF blend, and (2) ALT used to manufacture a PEF blend. The PEF blends were then used to manufacture 2 experimental MR. Both MR were formulated to contain a ratio of 22% CP to 20% fat with Met, Lys, Thr, Trp, and Val AA specifications, and fed twice per day along with ad libitum 22% CP mini-pelleted calf starter (CS) and water. The MR were fed at 15% solids at 0630 and 1800 h, fed at 0.567 kg/d for d 1 to 14, increased to 0.85 kg/d for d 15 to 35, and reduced to once per day at 0.425 kg/d for d 36 to 42 to facilitate weaning at 42 d with ad libitum CS fed for the remainder of the 56-d study. Calves fed CWG and ALT PEF blends were similar (P > 0.10) in BW gain (37.4 and 35.9 kg for CWG and ALT, respectively), ADG (679.8 and 652.7 g/d), CS DMI intake (0.69 and 0.67 kg/d), total DMI (1.19 and 1.17 kg/d) and feed conversion (0.559 and 0.543 kg/kg). No significant differences were detected in frame gains and fecal scores among treatments. Choice white grease can be used to manufacture a PEF blend for use in manufacturing MR for feeding neonatal calves by maintaining growth performance and health at potentially lower cost.
蛋白质包裹脂肪（PEF）混合物常用于生产犊牛代乳粉（MR）。使用PEF混合物可提高脂肪的可混合性，以确保在为新生犊牛混合并作为均匀溶液投喂时的MR质量。一种基于精选白油脂（CWG）的新型替代PEF已被开发出来，以提高其可混合性和溶解性，确保得到均匀的MR溶液。据推测，这种替代PEF能支持新生犊牛具有相似的生长性能（平均日增重、干物质采食量和饲料效率），并有可能降低成本。本研究的目的是评估CWG PEF作为标准动物猪油-牛油（ALT）PEF混合物的替代品，用于混合一种投喂给荷斯坦犊牛的MR。总共40头荷斯坦公牛犊（2 - 5日龄）按体重进行分组，并使用随机完全区组设计随机分配到2种处理中的1种（每组n = 20）。处理方式为：（1）使用CWG生产PEF混合物；（2）使用ALT生产PEF混合物。然后将PEF混合物用于生产2种实验性MR。两种MR均配制为含有22%粗蛋白与20%脂肪的比例，并符合蛋氨酸、赖氨酸、苏氨酸、色氨酸和缬氨酸的氨基酸规格，每天投喂两次，同时自由采食22%粗蛋白的小型颗粒状犊牛开食料（CS）和水。MR在0630和1800时以15%的固形物含量投喂，第1至14天每天投喂量为0.567千克，第15至35天增加到0.85千克/天，第36至42天减少到每天一次，投喂量为0.425千克/天，以便在42天时断奶，在为期56天的研究剩余时间内自由采食CS。投喂CWG和ALT PEF混合物的犊牛在体重增加（CWG和ALT分别为37.4千克和35.9千克）、平均日增重（679.8克/天和652.7克/天）、CS干物质采食量（0.69千克/天和0.67千克/天）、总干物质采食量（1.19千克/天和1.17千克/天）以及饲料转化率（0.559千克/千克和0.543千克/千克）方面相似（P > 0.10）。各处理之间在体躯生长和粪便评分方面未检测到显著差异。精选白油脂可用于生产PEF混合物，以用于生产投喂新生犊牛的MR，通过维持生长性能和健康状况，有可能降低成本。
