This experiment was one in a series to determine the response by fee dlot heifers to various growth promoting products . Products tested were diethylstilbestrol (DES), zeranol and melengestrol acetate (MGA) under conditions of high-concentrate diets with high-moisture grain and hay or haylage

Burkhardt, J.D.

Embry, L.B.

English

Public Research Access Institutional Repository and Information Exchange

South Dakota State UniversityOpen PRAIRIE: Open Public Research Access InstitutionalRepository and Information ExchangeSouth Dakota Cattle Feeders Field Day Proceedingsand Research Reports, 1973 Animal Science Reports1973Growth Stimulating Products for Feedlot HeifersFed High-Concentrate Diets of High-MoistureCornJ.D. BurkhardtSouth Dakota State UniversityL.B. EmbrySouth Dakota State UniversityFollow this and additional works at: http://openprairie.sdstate.edu/sd_cattlefeed_1973Part of the Animal Sciences CommonsThis Report is brought to you for free and open access by the Animal Science Reports at Open PRAIRIE: Open Public Research Access InstitutionalRepository and Information Exchange. It has been accepted for inclusion in South Dakota Cattle Feeders Field Day Proceedings and Research Reports,1973 by an authorized administrator of Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange. For moreinformation, please contact michael.biondo@sdstate.edu.Recommended CitationBurkhardt, J.D. and Embry, L.B., "Growth Stimulating Products for Feedlot Heifers Fed High-Concentrate Diets of High-MoistureCorn" (1973). South Dakota Cattle Feeders Field Day Proceedings and Research Reports, 1973. Paper 7.http://openprairie.sdstate.edu/sd_cattlefeed_1973/7S outh Dakota S tate University Brookings , South Dakota Department of Animal S ci ence Agricultural Experiment S tation A . S .  S eries 7 3-35 Growth Stimulating Products for Feedlot Heifers Fed High-Concentrate Diets of  High-Moisture Corn with Hay or Haylage J .  D .  Burkhardt and L. B .  Embry This experiment was one in a series to determine the response by fee dlot heifers to various growth promoting product s .  Products tested were diethylstilb es trol ( DES ) , z eranol and melenges trol acetate (MGA) under conditions of high-concentrate die ts with high-moisture grain and hay or haylage . Procedure Fif ty-six Hereford heifers were used in this experimen t .  They were allotted into 8 pens with 7 animals per pen .  The experimental diets were composed of 1 lb . of a 40% protein supplement , 2 lb . roughage dry matter and a full feed of rolled , reconst ituted , high-moisture corn ( 24 . 5% moi sture) . All animals received 20 , 00 0  I . U .  o f  vitamin A and 70 mg . bac itracin per head daily . Four pens were fed dry , chopped , alfalfa-brome hay ( 13% moisture)  and the other four pens received haylage ( 52 . 8% moisture) .  The haylage was from the same source as the hay but was recons tituted and stored in an oxygen-limiting silo (Harves tore) . Growth promo ting experimental treatments were control , 36 mg. zeranol implants , 1 0  mg .  DES per head per day or 0 . 4  mg . MGA per head per day . Each of these treatments was adminis tered to cattle fed hay or haylage . The cattle were fed for 1 2 7  days and the experiment terminated . At time of slaughter the livers were examined for abs cesses and carcass measurements were taken af ter an 1 8-hour chi ll .  Results Growth Promoting Products Results of the experimen t with the growth promoting products averaged for hay and haylage diets are presented in table 1 .  Weight gains were high for the heifers during this 1 2 7-day experiment . Heifers fed 10 mg . DES or 0 . 4  mg . MGA daily gained at essentially the same rate . The improvement over controls was 6 . 4% .  Heifers imp lanted with 36 mg . zeranol gained at a lower rate than those fed DES or MGA ( 3 . 4% more than controls) . Prepared for the Seventeenth Annual Cattle Feeders Day , November 2 ,  1973 . 3 1  - 2 -Feed consumption was about the same for all treatment groups includi ng the control . T here were slight improvements i n  feed effi ciency from the growth promoti ng compounds. T he percentage improvements amounted to 5 . 7 ,  4 . 7  and 3 . 5 ,  respecti vely, for DES , MGA and zeranol over control hei fers. D ifferences i n  carcass characteristi cs measured were small .  Hei fers fed DES had a lower dressing percent, less marbli ng, less fat thickness, a lower carcass grade but a larger rib eye in  comparison to the controls. Those fed MGA were qui te similar to controls but wi th less fat coveri ng. Hei fers implanted wi th zeranol appeared to di ffer from controls mainly in  a larger rib eye and less fat covering .  Hay vs. Haylage Results of comparisons between hay and haylage averaged for the growth promoti ng products are presented in table 2 .  Rate of gain was sli ghtly hi gher f or the heifers fed haylage ( 2 . 3%) . Feed intake ( 90% dry matter) was about the same f or hay and haylage with about the same di ffere nce in  feed ef fi ci ency ( 2 . 1%)  as for rate of gai n  in favor of haylage. T here appeared to be no important di fferences in carcass characteristi cs of hei fers fed hay or haylage. I ncidences of abscessed li vers were 5 for haylage­fed group ( 1 7 . 9%)  and 8 for hay-fed group ( 28 . 6%) . Summa;:y Feed lot hei fers were fed alfalf a-bromegrass hay or reconsti tuted haylage with reconstituted high-moisture corn i n  conj unction wi th di ethylsti lbestrol (DES ), meleng estrol acetate (MGA) or zeranol from wei ghts of about 590 to 9 80 lb. DES at 10 mg .  daily or MGA at 0 . 4  mg. daily resulted i n  about t he same improvement ( 6 . 4%) in weight gai n  over controls. Response to zeranol implants ( 36 mg. ) was at a lower rate ( 3 . 4%) . T here were small improvements i n  feed effi ci ency, 5 . 7 ,  4 . 7  and 3 . 5% ,  respectively, for DES , MGA and zeranol . T he DES treatment appeared to result in  a slightly lower dressing percent, less marbling , less fat thi ckness but a larger rib eye. Z eranol appeared to have simi lar but less pronounced effects as DES on carcass characteristi cs. Carcasses from heifers fed MGA were similar to controls. D i fferences in rate of gai n and feed effici ency between hay and haylage were qui te small , 2 . 3% more gain wi th 2 . 1% less feed i n  favor of haylage. However, the forages made up only a bout 10% of the rati on d ry matter . Converted to a ton of forage dry matter, the small di ff erences became rather substantial . The economi c  i mportance would depend upon the consistency in performance o f  cattle under the treatments .  3 2  - 3 -Table 1 .  Growth Promoting Products for Feedlot Heifers (June 15 to Oct . 20 , 1972-- 127 days) Control Number 14 Init. wt . , lb . 591  Final wt. ,  lb . 967 Avg. daily gain , lb . 2 . 96 Avg . daily feed , lb . ( 90% dry matter) Rolled high-moisture corn 17 . 27 Hay or haylage 2 . 04 Protein suppl .  0 . 99 Total 20. 30 Feed/100 lb . gain , lb . ( 90% dry matter) Rolled high-moisture corn 583 Hay or haylage 69 Protein suppl . 33 Total 685 Carcass wt . ,  lb . 604 Dressing percent 62 .4  ConformaEiona 2 1 . 4  Marbling 5 . 5  Carcass gradea 18 . 9  Maturityc 23 . 0  Colord 4 . 6  Firmnesse 6. 2 % kidney fat 2 . 8  Loin eye area , sq . in . 9 . 66 Fat depth , in . 0 . 68 Abscessed livers 3 Zeranol 36 mg. implant 14 590 979 3 . 06 17 . 23 2 . 04 0 . 99 20 . 26 563 67 32 662 6 1 1  62 . 3  2 1 . 0  5 . 7  19 . 0  23 . 0  4 . 7 6. 1 3 . 0  10 . 28 0 . 53 2 DES 10 mg . daily 14 589 989 3. 15 17 . 36 2 . 04 0 . 99  20 . 39 551 65 31  647 612 61 . 9  21 . 1  5 . 0  18 . 6  2 3 . 0  4 . 6  6 . 0  2 . 8  1 0 . 16 0 . 58 5 aGood = 17 ; Choice = 20 . Graded to one-third grade . bslight = 4 ;  Small = 5 ;  Modest = 6 .  CA+ maturity = 22 ; A maturity • 23.  dcherry red • 4;  Light cherry red = 5 .  eModerately firm = 5 ;  Firm = 6 .  3 3  MGA 0 . 4 mg . daily 14 59 1 990 3 . 14 17 . 48 2 . 04 0 .9 9  20 . 5 1  557 65 32 654 616 62 . 2  21 . 4  5 . 5  19 . 0  23 . 0  4 . 9  5 . 9  3 . 0  9 . 81 0 . 59 3 - 4 -Table 2 .  Hay or Haylage with Rolled High-Mois ture Corn (June 15 to Oct .  20 , 19 72-- 127 days) Number Init . wt . , lb . Final wt . , lb . Avg . daily gain , lb . Hay 28 59 1 978  3 . 04 matter) Avg . daily feed , lb . ( 90% dry Rolled high-moisture corn Hay or haylage 17 . 36 2 . 02 0 . 99 20 . 37 dry matter) Protein suppl .  Total Feed/ 100 lb . gain , lb . ( 9 0% Rolled high-moisture corn Hay or haylage Protein suppl .  Total Carcass wt . , lb . Dressing percent Conf ormationa Marblingb Carcass gradea Maturityc Colord Firmnesse % kidney fat Loin eye area, sq . in .  Fat depth , in . Abscessed livers 5 7 1  66  33 670 607 62 . l  2 1 . 3  5 . 6 18 . 9  23 . 0  4 . 5  6 . 0  2 . 9  9 . 92  0 . 56 8 Haylage 28 589 985 3 . 1 1  1 7 . 32 2 . 0 7  0 . 99 20 . 38 557 6 7  32 656 6 14 62 . 3  2 1 . 2  5 . 3  18 . 9  23.0  4 . 9  6 . 1  2 .9 10 . 04 0 . 63 5 aGood = 1 7 ;  Choice = 20 . Graded to one-third grade . bS light = 4 ;  Small = 5 ;  Modest = 6 .  CA+ maturity = 22 ; A maturity = 23 . dcherry red = 4 ;  Light cherry red = 5 .  eModerately firm = 5 ;  Firm = 6 .  3 4  

Growth Stimulating Products for Feedlot Heifers Fed
High-Concentrate Diets of High-Moisture Corn

https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=1006&context=sd_cattlefeed_1973

Growth Stimulating Products for Feedlot Heifers Fed High-Concentrate Diets of High-Moisture Corn

Abstract

Similar works

Full text

Available Versions

Public Research Access Institutional Repository and Information Exchange