Portal de Periódicos da CAPES

Growth Studies with Calves and Rabbits Fed Timothy Hay Grown on Heavily Fertilized Soils,

1958; Elsevier BV; Volume: 41; Issue: 1 Linguagem: Inglês

10.3168/jds.s0022-0302(58)90882-8

1529-9066

H. A. Keener, Edward J. Thacker,

Ruminant Nutrition and Digestive Physiology

This experiment was conducted to identify nutritional deficiencies in timothy hay grown on a henvily fertilized soil.When this h~v was fed to calves with tl concentrate mixture of deg'ermed corn meal, nonfat dry mi'lk solids or urea, vitmnins A and D, cobalt, calcium, phosphm'us, and common sa]t, the ration was deficient in iron, copper, nnd iodine, resulting in poor growth, poor appetite, anemi~ b and enlarged thyroids.Feeding iron and copper, either individually or in combination, did not correct these symptoms.Iodine supplementation corrected the thyroid condition but did not stimulate growth.When similar h~v was fed to r~hbits in a ration SUl)plemented with wheat gluten, hydrogenat(,d w'getnble oil, dextrose, sodium chloride, and vitmnins A and D, it also resulted in poor g'rowth, mwmbl, ~nd in(,re~lsed thyroid weight.F(,eding of :l ration (.ontaining 5% Mi'Mt'n prevented MI these symptoms, but an equivnlent atllOUllt of alf~flfa ~lsh or iodine 1)revented only the enb~rged thyroid.The timothy h~y apparently w:ls deficient in iodine ~m(t some org;mic f~(,tm'(s) whi(,h m~ly be found in MfMI';~ lmy.An exf)eriment which has t)eeu in l)rogress at the N(,w llampshir(, Agrieultin'at Experiment Station for a I)eriod of several years has shown that (,m'tain forage ('roi)s ~'rown under (,onditions of heavy al)t)lieations of NI)K fertilizers to the soil may be h)w in iron, eOpl)('r, ('obalt, and magnesimn.When such forages were fed to dairy ealv~'s, along with a low ~ra('(, min(,rM ~'on('entrate mixtur(~ containing supplemental vitmnins A and l), e~d('ium, phosphorns, cobalt, and common sail they resulted in I)oor growth, anemia, sagging' of the sI)imd eohmm behind the shoulders, and other symptoms.In mature mfimals, the feeding of this type of ration has resulted in rapid loss of flesh after calving, poor milk production and, in many instam.es, in the ])roduetion of goitrous calves.Rabbits fed similar forages have shown poor growth, mild anemia, and hyperplasti(, thyroids.