Effects of base ingredient in cooked molasses blocks on intake Effects of base ingredient in cooked molasses blocks on intake and digestion of prairie hay by beef steers and digestion of prairie hay by beef steers

Twelve steers (332 kg) were used in three simultaneous 4 x 3 incomplete Latin squares to evaluate effects of beet molasses (BEET), cane molasses (CANE), or concentrated separator by-product (CSB) as base ingredients in cooked molasses blocks on intake and digestion of prairie hay and ruminal characteristics. All steers had ad libitum access to prairie hay (5.9% CP and 69.4% NDF; DM basis). The four experimental treatments included a control (no supplement) and three cooked molasses blocks, based on BEET, CANE, or CSB, fed daily at .125% of BW (.42 kg/d as-fed, .13 kg/d CP). Forage OM, NDF, and N intakes; digestible OM, NDF, and N intakes; and total tract OM and N digestibilities (percentage of intake) were greater (P < .05) for steers fed cooked molasses blocks than for control steers. Total tract OM digestibility was greater (P < or = .06) for steers fed BEET blocks (54.0%) than for those fed CSB (52.1%) or CANE blocks (52.2%). Digestion of NDF was greatest (P < .05) for steers fed BEET blocks (51.9%) and tended to be greater (P < .07) for steers fed CANE (49.3%) or CSB blocks (49.3%) than for control steers (46.9%). Ruminal ammonia concentrations were greater (P < .05) for steers fed cooked molasses blocks (.89 mM) than for control steers (.21 mM); this was primarily due to increases to 4.6 mM at 2 h postfeeding for steers fed blocks. Concentrations of total VFA in ruminal fluid were greater (P < .05) for steers fed BEET (92.7 mM) and CSB (88.1 mM) blocks than for control steers (80.3 mM), whereas concentrations for steers fed CANE blocks were intermediate (85.4 mM). Steers supplemented with cooked molasses blocks had greater molar percentages of butyrate than did control steers, particularly shortly after feeding. In summary, supplementation with cooked molasses blocks increased forage intake and digestion. The three base ingredients elicited similar responses, although steers fed BEET had slightly greater OM and NDF digestibilities than those fed CANE or CSB.


Summary
Blocks based on cooked beet molasses, cane intake and digestion and, thus, energy available to molasses, or concentrated separator by-product, cattle, supplements containing ruminally degradable CSB) were tested to compare their effects on protein are often fed.Previously, we demonstrated intake and digestion of prairie hay by beef steers.
that cooked molasses blocks (based on beet molas-All blocks contained at least 30% crude protein. ses) containing 30% crude protein (12% from Steers fed the cooked molasses blocks consumed nonprotein nitrogen) increased forage intake and 22% more forage than control steers, but forage digestion.intakes were not different among the three different blocks.Intakes of digestible organic matter and Various molasses products including beet neutral detergent fiber, indicators of energy avail-molasses, cane molasses, and concentrated separaable to the steers, were increased 38 and 29% tor by-product (CSB, desugared beet molasses) are respectively, by block supple-mentation but were available for use as base ingredients in cooked not different among the three blocks.However, molasses blocks.Composition of cooked molasses total tract organic matter and neutral detergent blocks may vary with availability and(or) cost of fiber digestibilities, expressed as a percent of base ingredients.Alterations in base ingredients intake, were slightly higher for steers fed the beet will affect the source and quantity of carbohymolasses block than those fed the cane molasses drates, protein, and minerals added to blocks.Our block or the CSB block.
In summary, objective was to evaluate effects of blocks with supplementation with cooked molasses blocks that similar nutrient composition but different ingredient contained adequate degradable protein increased composition on intake and digestion of prairie hay forage intake and digestion.Generally, blocks by beef steers.made from the different by-products elicited similar responses, though steers fed the beet molasses product tended to have greater digestibilities than those fed blocks made from cane molasses or Twelve steers (730 lb) were used in three concentrated separator by-product.simultaneous 4×3 incomplete Latin squares.The cooked molasses blocks were formulated to be not (Key Words: Steers, Forage, Intake, Digestibility, less than 30% crude protein, of which not more Cooked Molasses Blocks.)than 12% equivalent crude protein was provided by

Introduction
Deficiencies of degradable intake protein can not receive molasses blocks.Steers were provided reduce digestion of dormant forage, which, in turn, 20 grams of salt daily and ad libitum access to can limit forage intake and reduce the energy available to grazing cattle.To increase forage

Experimental Procedures
nonprotein nitrogen (urea).Predominant ingredients were beet molasses, cane molasses, or CSB; animal fat; plant and animal proteins; and processed grain by-products.The cooked molasses blocks were fed daily at a level of .92lb (as-is basis) which provided .28lb crude protein.Control steers did water and prairie hay.Hay contained 5.9% crude differences in digestibilities among the steers fed protein and 69.4% neutral detergent fiber (NDF) the three different blocks indicates that the blocks (dry matter basis).Experimental periods were 18 containing different base ingredients had similar days with a 12-day adaptation period followed by attributes.6-day intake and total fecal collection period.Orts and fecal samples were collected daily in the morn-Ruminal ammonia concentrations increased ing in order to calculate forage intake and diges-(P<.05)when steers were fed any of the three tion.On day 12, ruminal fluid was collected at blocks (average of .89vs .21mM for control feeding and 2, 4, 6, 8, 10, and 12 hours post-steers), reflecting the additional degradable protein feeding for analysis of ammonia and volatile fatty that the cooked molasses blocks supplied.Total acids (VFA).
ruminal fluid VFA concentrations were greater (P<.05) for steers fed the beet molasses or CSB

Results and Discussion
Forage intakes, digestible organic matter ate.The elevation in total ruminal fluid VFA intakes, and total tract organic matter digestibilities among steers fed the cooked molasses blocks was (% of intake) were greater (P<.05) for steers fed primarily a function of the increase in forage ferany of the three cooked molasses blocks than for mentation, which was shown by the increase in control steers (Table 1).The increase in digestible digestible organic matter and NDF intakes.Howorganic matter intake, an indicator of energy ever, some VFA could be attributed to sugar in the available to the steers, was likely a response to blocks.increased degradable intake protein provided by the cooked molasses blocks.Forage intakes and In conclusion, supplementation with cooked digestible organic matter intakes were not different molasses blocks increased forage intake and digesamong steers fed the three different blocks.Total tion, ruminal ammonia, and total ruminal VFA.tract organic matter and NDF digestions (percent Digestible organic matter increased by an average of intake) were slightly higher for steers fed the of 38% when steers were fed the cooked molasses beet molasses block than for steers fed the cane blocks, probably because they supplied additional molasses or CSB block.The lack of difference in ruminally degradable protein, which allowed for digestible organic matter intakes and the relatively increased forage digestion.Generally, the blocks small based on beet molasses, cane molasses, and CSB block than for control steers, whereas those for steers fed the cane molasses block were intermedielicited similar responses, although steers fed the beet molasses block tended to have greater digestibilities.

Table 1 . Effects of Different Base Ingredients in Cooked Molasses Blocks on Intake and Digestion of Prairie Hay by Steers and Ruminal Parameters
1 Means within rows without common superscript differ (P<.05).a, b, c