Cozzi G, Gottardo F, Mattiello S, Canali E, Scanziani E, Verga M, Andrighetto I
Dipartimento di Scienze Zootecniche, Università degli Studi di Padova, Legnaro (PD), Italy.
J Anim Sci. 2002 Feb;80(2):357-66. doi: 10.2527/2002.802357x.
Growth performance, forestomach development, and carcass and meat quality of veal calves fed a milk replacer diet (Control) were compared to those obtained from calves fed the same liquid diet plus 250 g x calf(-1) x d(-1) of dried beet pulp or wheat straw. Three groups of 46 Polish Friesian calves, balanced according to initial BW, were assigned to the three dietary treatments in a fattening trial, which lasted 160 d. The provision of either solid feed did not affect the milk replacer intake. However, calves' ADG was increased (P < 0.01) only by feeding the beet pulp diet. The administration of both solid feeds improved calves' health status; calves fed solid feeds required fewer iron treatments for low hemoglobin and needed less medical treatments for respiratory or gastrointestinal diseases. In comparison to the Control calves, the provision of wheat straw and beet pulp increased iron intake throughout the fattening period by 41 and 130%, respectively. However, only calves fed beet pulp showed higher levels of hemoglobin and plasma iron concentrations (P < 0.05), whereas the same blood parameters were similar between Control calves and those fed wheat straw. At slaughter, both solid feeds led to empty forestomach weights heavier than those of Controls without reducing dressing percentage. The reticulorumen was heaviest in calves fed beet pulp, whereas wheat straw promoted omasal development. The administration of beet pulp resulted in a better carcass conformation than did the Control diet or wheat straw, but it had a detrimental effect on carcass color, which was graded as the darkest (P < 0.001). Consistent with this result, meat color of calves fed beet pulp was darker than that of Control calves and those fed wheat straw, because of the higher hematin concentration measured at the muscle level. No differences in carcass and meat color were observed between Control calves and calves fed wheat straw. The administration of solid feeds for welfare purposes does not always prevent the production of veal meat fulfilling the color standards required by the market. There is not a straight-forward relationship between a solid feed's iron content and the "redness" of veal meat, which should be related to the capability of the calves to use the iron provided by the roughage.
将饲喂代乳粉日粮（对照组）的犊牛的生长性能、前胃发育、胴体和肉质，与饲喂相同液体日粮并添加250克/头·天干甜菜粕或小麦秸秆的犊牛所获得的相应指标进行比较。在一项持续160天的育肥试验中，将三组46头波兰黑白花犊牛（根据初始体重进行均衡分组）分配至三种日粮处理组。提供任何一种固体饲料均不影响代乳粉的摄入量。然而，仅饲喂甜菜粕日粮可提高犊牛的平均日增重（P<0.01）。两种固体饲料的投喂均改善了犊牛的健康状况；饲喂固体饲料的犊牛因血红蛋白水平低而需要的补铁处理更少，因呼吸道或胃肠道疾病所需的药物治疗也更少。与对照组犊牛相比，在整个育肥期，提供小麦秸秆和甜菜粕分别使铁摄入量增加了41%和130%。然而，仅饲喂甜菜粕的犊牛血红蛋白水平和血浆铁浓度更高（P<0.05），而对照组犊牛和饲喂小麦秸秆的犊牛的相同血液参数相似。屠宰时，两种固体饲料均使前胃空重比对照组更重，且未降低屠宰率。饲喂甜菜粕的犊牛网瘤胃最重，而小麦秸秆促进了瓣胃发育。与对照组日粮或小麦秸秆相比，投喂甜菜粕使胴体外形更好，但对胴体颜色有不利影响，胴体颜色被评为最暗（P<0.001）。与此结果一致，饲喂甜菜粕的犊牛肉色比对照组犊牛和饲喂小麦秸秆的犊牛更暗，这是因为在肌肉水平测得的高铁血红素浓度更高。对照组犊牛和饲喂小麦秸秆的犊牛在胴体和肉色方面未观察到差异。出于福利目的投喂固体饲料并不总能防止生产出符合市场要求颜色标准的小牛肉。固体饲料的铁含量与小牛肉的“红色度”之间不存在直接关系，小牛肉的“红色度”应与犊牛利用粗饲料提供的铁的能力有关。
