Value Added Opportunities from the Manufacture and Feeding of Silages Produced from Liquid Cheese Whey and Other By-products to Growing and Finishing Cattle and Beef Cows
These studies showed that liquid cheese whey can be combined with other residue feeds, such as wheat middlings and cereal straw, to produce a nutritious and palatable feedstuff. Growing beef steers and holstein heifers fed whey silage had a lower cost of gain and were as efficient as their counterparts which were fed typical growing diets When whey silage was substituted for corn silage in finishing steer diets feed efficiency was not affected but cost of gain was slightly decreased. Whey silage is a viable alternative for cattle producers but its use should be based on economic considerations.
1. Determine production and carcass characteristics of growing and finishing cattle and beef cows under maintenance conditions fed ensiled products that were derived from combining "sweet" or "acid" liquid cheese whey, low-quality roughage sources and a concentrate source.
2. Determine nutrient content of these derived silage products.
3. Evaluate economics of production for whey silage compared to traditional corn silage based diets and for cattle fed these silages.
4. Disseminate research results derived from these studies to beef producers, extension and industry personnel in the Intermountain West.
A novel whey silage (WS) was produced in bunker silos by combining liquid cheese whey (50% DM) with wheat straw (S) and wheat middlings (WM) at proportions of 63.1%, 28.9% and 8.0% (DMB) respectively. Nutrient and fermentation analysis of the WS (30d ensiling period) indicated approx. 44.8% DM, 14.3% CP, 1.87 Mcal/kg NEm, 1.23 Mcal/kg NEg, 4.3 pH, 10.5% lactic acid and 11.2% total VFA (DMB). Sixty weaned beef steers were assigned either Control (C), Treatment 1 (T1) or Treatment 2 (T2). There were 5 steers per pen and 4 pens per treatment for this 56d trial. The C steers received 19.0% alfalfa hay (AH), 32.4% corn silage (CS), 39.9% rolled barley (RB), 5.6% SBM and 3.1% supplement and T1 and T2 steers received 24.8%CS, 31.0% WS, 35.7% RB, 5.2% SBM and 3.3% supp. or 65.5% WS, 31.3% RB and 3.2% supp. Respectively. All rations were isocaloric and isonitrogenous. Overall ADG (kg), DMI (kg) and FE for C, T1 and T2 steers were 1.18, 1.25 and 1.34 (P=.14); 7.09, 8.68 and 9.36 (P=.0001); 6.04, 7.01 and 7.07 (P=.04) respectively. In vivo DM and NDF digestibilities were similar when comparing C and T2 diets (P>.05).
In other studies, cheese whey silage (WS) was produced at two separate locations to determine the effect of feeding WS on production characteristics of growing holstein heifers (HH) and finishing beef steers (BS). For the HH study, WS was produced by combining liquid cheese whey (W), wheatgrass straw (WGS) and wheat middlings (WM) at proportions of 51.5, 38.3 and 10.2% (DMB) respectively and ensiling for 30 days prior to feeding. The WS had a DM nutrient analysis of 46.4% DM, 13.8% CP, 17.3% ADF, 27.4% NDF, .59% Ca, .56% P, and pH of 3.9. Forty-eight HH (258 kg) were assigned to treatments of Control (C) or Treated (T) with eight head per pen and three pens per treatment for this 56 d study. The C heifers received a growing ration with DM proportions of 16.6% alfalfa hay (AH), 40.4% corn silage (CS), 41.0% WM and 2.0% supplement (S). Treated HH received the WS and supplement. Control and T rations were isocaloric and isonitrogenous. For the BS study, WS was produced by combining and ensiling W, wheat straw and WM at DM proportions of 63.1, 28.9 and 8.0% respectively. The WS had a DM nutrient analysis of 43.5% DM, 13.3% CP, 19.9% ADF, 28.4% NDF, .64% Ca, .67% P, and pH of 4.3. Forty steers (438 kg) were assigned to treatments of C or T with five head per pen and four pens per treatment in this 84 d study. Control steers received a diet consisting of 85.6% dry-rolled barley (B), 8.1% CS, 1.5% SBM and 4.8% S (DMB). Treated steers received 84.1% B, 12.2% WS and 3.8% S (DMB). The C and T rations were isocaloric and isonitrogenous. All steers were slaughtered together, with marketing time determined by ultrasound scan and carcass data recorded. Both studies were a completely randomized design where pen was the experimental unit and calves were stratified by weight and age and assigned to treatment. Statistical analysis of data for both studies were performed using the MIXED procedure of SAS. Results from the HH study indicated ADG (kg×d-1), DMI (kg×d-1) and FE values for C and T of 1.09 and 1.06 (P=.79); 8.0 and 6.55 (P=.11); and 7.38 and 6.52 (P=.32) respectively. Finishing steer results for C and T respectively were 1.11 and 1.20 (P=.15) for ADG (kg×d-1); 9.05 and 9.73 (P=.006) for DMI (kg×d-1); and 8.26 and 8.22 (P=.93) for FE. There were no differences between treatments for any of the carcass traits measured (P>.05). Although production variables were not different, cost of gain was decreased by 35.3% and 5.7% respectively for the HH and BS studies, due to the lower cost of the T rations. These studies suggest there may be an economic basis for including whey silage in growing and finishing diets.
Impacts and Contributions/Outcomes
The Intermountain West has a number of cheese and yogurt plants that produce, as a by-product, thousands of tons of liquid whey. Whey is categorized as "sweet" or "acid", depending on the manufacturing procedure employed for specific cheese types. Within this same geographic area there is an abundance of low-quality roughage sources. The utilization of the residue from low-quality roughages provide another marked benefit. Residue from grain crops are often burned in the fall which is an environmental concern in some areas. Future sustainability of agriculture will be also depend on environmental stewardship. These studies show that sweet liquid whey can be combined with other residue feeds resulting in a low-cost alternative to traditional roughage used in growing and finishing cattle diets. Cost of gain in all cases was decreased when whey silage was fed. Future research will focus on the use of cheese whey silage in beef cow maintenance diets and growing diets using acid whey to produce whey silage. There are great opportunities for these residue feeds.
Completed studies have been reported at scientific conferences and an extension publication has been produced summarizing the results to date. A number of interested cattle producers and others have contacted the study coordinator for more information. Over the coming year further investigation will continue providing additional data that will be disseminated to the scientific community and cattle industry .