Effects of reducing inclusion rate of roughages by changing roughage sources and concentrate types on intake, growth, rumen fermentation characteristics, and blood parameters of Hanwoo growing cattle (Bos Taurus coreanae)

Abstract

ObjectiveReducing roughage feeding without negatively affecting rumen health is of interest in ruminant nutrition. We investigated the effects of roughage sources and concentrate types on growth performance, ruminal fermentation, and blood metabolite levels in growing cattle.MethodsIn this 24-week trial, 24 Hanwoo cattle (224±24.7 kg) were fed similar nitrous and energy levels of total mixed ration formulated using two kinds of roughage (timothy hay and ryegrass straw) and two types of concentrate mixes (high starch [HS] and high fiber [HF]). The treatments were arranged in a 2×2 factorial, consisting of 32% timothy–68% HS, 24% timothy–76% HF, 24% ryegrass–76% HS, and 17% ryegrass–83% HF. Daily feed intakes were measured. Every four weeks, blood were sampled, and body weight was measured before morning feeding. Every eight weeks, rumen fluid was collected using a stomach tube over five consecutive days.ResultsThe mean dry matter intake (7.33 kg) and average daily gain (1,033 g) did not differ among treatments. However, significant interactions between roughage source and concentrate type were observed for the rumen and blood parameters (p<0.05). Total volatile fatty acid concentration was highest (p<0.05) in timothy–HF-fed calves. With ryegrass as the roughage source, decreasing the roughage inclusion rate increased the molar proportion of propionate and decreased the acetate-to-propionate ratio; the opposite was observed with timothy as the roughage source. Similarly, the effects of concentrate types on plasma total protein, alanine transaminase, Ca, inorganic P, total cholesterol, triglycerides, and creatinine concentrations differed with roughage source (p<0.05).ConclusionDecreasing the dietary roughage inclusion rate by replacing forage neutral detergent fiber with that from non-roughage fiber source might be a feasible feeding practice in growing cattle. A combination of low-quality roughage with a high fiber concentrate might be economically beneficial.

Effects of dietary supplementation with different concentration of molasses on growth performance, blood metabolites and rumen fermentation indices of Nubian goats

“…The concentration of ruminal NH 3 -N is an effective indicator of ruminal microbes’ activity [ 40 ]. The minimum concentration of ruminal NH 3 -N needed for microbial protein synthesis is 5 mg/dL [ 41 , 42 ], while a range of 10–20 mg/dL is required for an optimum concentration for fiber degradation [ 43 ]. The concentration of ruminal NH 3 reported in the current study exceeded 5 mg/dL and ranged between 7.6 and 10.5 mg/dL.…”

Effects of fibre source on nutrient digestibility of diets for finishing lambs

“…Feeding high-concentrate diets to finishing lambs generally improves lamb performance (Jabbar & Anjum, 2008;Shivambu et al, 2011). However, lamb feedlot diets require a minimum amount of fibre to ensure normal rumen functioning, which differs according to the chemical and physical properties of the fibre source (Jeon et al, 2019). Lucerne hay is usually the primary fibre source that is used in high-producing animals such as growing lambs, but it can be expensive and its quality varies.…”

Performance, carcass traits and meat quality of lambs fed with different roughage: concentrate ratios associated with variable physically effective neutral detergent fibre content

“…Voluntary DMI is a mechanism that can be affected by associated or isolated factors such as physical (physical satiety by filling the gastrointestinal tract) or physiological (chemical satiety) and the quality of the food (Araújo et al ., 2017; Jeon et al ., 2019). The concentrate intake tends to influence the total DMI and also its constituents (such as nitrogen compounds), since it is a more palatable and digestible diet component (Realini et al ., 2004; Jeon et al ., 2019).…”