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The aim of this study was to determine the effects of castration and a lidocaine-plus-flunixin (LF) treatment on growth and indicators of pain, inflammation, and liver function in Korean cattle bull calves. Forty Korean cattle bull calves (body weight 197.0 ± 2.94 kg and age 6.3 ± 0.09 months) were each assigned to one of four treatments (n = 10 heads/group): no castration with no LF injection (NC-NLF); no castration with LF injection (NC-LF); castration with no LF injection (C-NLF); and castration with LF injection (C-LF). LF treatment included a local anesthetic lidocaine hydrochloride injection (12 mL of 2% in the scrotum) and intravenous injection of a non-steroidal anti-inflammatory drug, flunixin meglumine (2 mg/kg body weight of 50 mg/mL solution), immediately prior to castration. For the NLF groups, a 0.9% NaCl placebo solution was used. Castration was performed surgically using a Newberry knife and a Henderson castrating tool. Blood was collected immediately before castration and at h 0.5, h 6, d 1, d 3, d 7, and d 14 after castration. Feed intake was recorded daily, and body weight was measured on the day prior to the experiment and at d 14 after castration. Castration tended (P = 0.07) to decrease average daily weight gain, but LF treatment did not affect weight gain. Castration increased both circulating cortisol concentrations (P

β-mannanase is an enzyme that breaks down mannan which is complex biopolymers commonly found in plant cell walls. It has been reported that supplementation of β-mannanase in a diet that composed of high mannan containing feedstuffs (e.g. palm kernel meal, copra meal, soy hull; HMCF) improves digestibility and utilization of livestock feeds. In ruminants, β-mannanase supplementation also increased growth rate of goats and Holstein calves. No study, however, has been conducted to evaluate the effect of β-mannanase supplementation in growing heifers. Moreover, little is known whether β-mannanase supplementation will have beneficial effects in conventional corn-soy based diets (CS). The objective of this study was thus to investigate the effect of supplementation of β-mannanase in Hanwoo growing heifers fed a diet composed of either a CS or HMCF based concentrate mix. For this purpose, a feeding trial was conducted for 12 weeks using a total of 40 Hanwoo growing heifers (BW: 236.2 kg±1.1 kg, 11 month of age). Total mixed rations (250 g/kg of ryegrass and 750 g/kg of concentrate mix) were offered ad libitum. The experimental design was 2×2 factorial approach with two different concentrate mixes (CS or HMCF based) and with or without a commercial feed β-mannanase (800,000 U/kg DM) product (CTCZYME®, CTC Bio Inc., Seoul, Korea) at a level of 1 g/kg in concentrate mixes. In both diets, supplementation of β-mannanase significantly increased ADG of Hanwoo heifers by 95 g/d on average (111 g/d or 90 g/d for CS and HMCF, respectively). No significant difference was observed in DMI among treatments, but β-mannanase supplementation tended to decrease feed conversion ratio (DMI/ADG) by 1.3 on average. The ADG of CS (943 g/d) was significantly greater than that of HMCF (854 g/d). These results indicated that supplementation of β-mannanase enhanced growth rate and feed efficiency of Hanwoo heifers regardless of the basal diets. Therefore, we conclude that supplementation of β-mannanase can be beneficial to improve the feed utilization in Hanwoo growing heifers.

The use of agricultural by-products possessing high β-mannan content as an animal feed ingredient has become increasingly important in achieving cost-effective agriculture. Recent studies showed improvement in growth performance from a diet containing high β-mannan concentrations by the addition of β-mannanase in monogastric animals. Few studies, however, have been conducted to examine the value of β-mannanase supplementation in ruminant diets. In the present study, the effects of β-mannanase supplementation on growth performance, nutrient digestibility, and nitrogen (N) utilization were investigated in growing Korean native goats (Capra hircus coreanae). Twelve Korean native goats (13±1.9 kg) were divided into three groups and randomly allocated into one of the following treatments: (1) control (CON), (2) 0.1% β-mannanase supplementation (TRT1), or (3) 0.3% β-mannanase supplementation (TRT2) in a concentrate mix based on dry matter (DM). Diets composed of 40% of tall fescue hay and 60% of each concentrate mix were formulated to meet the National Research Council requirements for indigenous goats. No difference was observed among treatments in terms of DM intake and highest DM and organic matter digestibility (P