The Ohio State University and The Ohio Agricultural Research and Development Center, Columbus 43210-1095.
J Anim Sci. 2013 Dec;91(12):5680-6. doi: 10.2527/jas.2013-6608. Epub 2013 Nov 18.
The dietary effects of Cu, Fe, Mn, and Zn levels, and the addition of Zn and Fe to a nonfortified, micromineral basal diet were evaluated in grower-finisher pigs. Growth, feed efficiency, hematology, carcass characteristics, and loin quality were assessed in growing-finishing pigs (n = 222; initial BW = 24 kg). Corn-soybean meal diets fortified with limestone and dicalcium phosphate with added phytase constituted the basal diets. A study was conducted with 6 dietary treatments and 7 replicates in a randomized complete block design. Treatments consisted of: 1) basal diet without added Cu, Fe, Mn, and Zn microminerals, 2) basal + 50% NRC Cu, Fe, Mn, and Zn requirements, 3) basal + 100% NRC Cu, Fe, Mn, and Zn requirements, 4) basal + 25 mg Zn/kg, 5) basal + 50 mg Zn/kg, and 6) basal + 50 mg Fe/kg. The microminerals were added as an organic mineral proteinate and all diets incorporated organic Se at 0.3 mg/kg. Diets were fed ad libitum over 3 growth phases. At 55, 80, and 115 kg BW, 3 pigs per pen were bled and hemoglobin (Hb) and percent hematocrit (Hct) were determined. At 115 kg BW, 3 pigs per pen were killed and carcass characteristics and loin quality measurements were determined. The ADG, ADFI, and G:F for each of the 3 dietary phases and overall period were not affected by dietary micromineral treatments. The concentration of Hb and percent Hct did not differ because of the treatment at each of the 3 phases. There were no treatment differences in carcass characteristics (HCW, backfat, or LM area). Loin pH, color (L*, a*, and b*), and drip loss did not differ by dietary treatment. Subjective marbling, color, and firmness scores, and intramuscular fat content of loins did not differ as the micromineral level increased above the 1998 and 2012 NRC requirements. The LM from pigs fed supplemental Fe had greater (P < 0.05) firmness and wetness scores than pigs fed the basal diet. These results indicate that there is sufficient amount of innate microminerals (Cu, Fe, Mn, and Zn) in a typical corn-soybean meal based diet to meet the grower-finisher pig's requirement for growth and hematological measurements. Although there was no detrimental effect by eliminating these microminerals from diets, it would seem that a dietary level of 50% of the NRC requirement for Cu, Fe, Mn, and Zn would be warranted.
研究了铜、铁、锰和锌水平的膳食影响，以及在非强化微量矿物质基础日粮中添加锌和铁对生长肥育猪的影响。在生长肥育猪（n=222；初始体重 24 公斤）中评估了生长、饲料效率、血液学、胴体特性和腰肉质量。玉米-豆粕日粮用石灰石和磷酸二钙强化，并添加植酸酶作为基础日粮。在随机完全区块设计中进行了 6 种日粮处理和 7 个重复的研究。处理包括：1）基础日粮，不添加铜、铁、锰和锌微量元素；2）基础+50%NRC 铜、铁、锰和锌需求；3）基础+100%NRC 铜、铁、锰和锌需求；4）基础+25mg/kg 锌；5）基础+50mg/kg 锌；6）基础+50mg/kg 铁。微量元素作为有机矿物蛋白盐添加，所有日粮均含有 0.3mg/kg 的有机硒。3 个生长阶段均自由采食日粮。在 55、80 和 115kgBW 时，每栏猪 3 头采血，测定血红蛋白（Hb）和红细胞压积（Hct）百分比。在 115kgBW 时，每栏猪 3 头屠宰，测定胴体特性和腰肉质量。3 个日粮阶段和整个阶段的 ADG、ADFI 和 G:F 不受日粮微量元素处理的影响。Hb 和 Hct 百分比在 3 个阶段均不因处理而不同。胴体特性（HCW、背膘厚或 LM 面积）无处理差异。腰肉 pH 值、颜色（L*、a和 b）和滴水损失不因日粮处理而不同。主观大理石花纹、颜色和嫩度评分以及腰肉的肌内脂肪含量随着微量矿物质水平的增加而高于 1998 年和 2012 年 NRC 要求时，没有差异。补充铁的猪的 LM 硬度和嫩度评分较高（P<0.05）比喂基础日粮的猪。这些结果表明，典型的玉米-豆粕基础日粮中含有足够数量的固有微量元素（铜、铁、锰和锌），足以满足生长肥育猪的生长和血液学测量需求。尽管从日粮中消除这些微量元素没有不利影响，但似乎需要 50%的 NRC 铜、铁、锰和锌需求水平。
