Effect of Rumen-Protected L-Tryptophan or L-Ascorbic Acid on Plasma Metabolites and Milk Production Characteristics of Lactating Holstein Cows during Summer Conditions.

This study investigated the effects of rumen-protected L-tryptophan or L-ascorbic acid supplementation on the productivity of lactating Holstein cows during a high-temperature period. Thirty cows were assigned to three dietary groups: control (CON), treatment 1 (TRT 1; rumen-protected L-tryptophan, 20 g/cow/d), and treatment 2 (TRT 2; rumen-protected L-ascorbic acid, 20 g/cow/d). As the high-temperature period progressed, the decrease in milk yield and dry matter intake (DMI) in the TRT 1 and TRT 2 groups was lower than that in the CON group. The total protein level in the plasma of the TRT 1 group was higher than that in the CON group (p < 0.05). Milk melatonin concentration was higher in the TRT 1 group than in the CON and TRT 2 groups (p < 0.05). Thus, the present results indicate that rumen-protected L-tryptophan or L-ascorbic acid has positive effects in preventing declines in DMI and milk yield by reducing heat stress in Holstein cows. In particular, rumen-protected L-tryptophan is considered effective in increasing the melatonin concentration in milk.

Effect of Lupin Supplementation on the Growth, Carcass, and Meat Characteristics of Late-Fattening Hanwoo Steers.

This study aimed to investigate the effects of lupin flake supplementation on the growth, plasma parameters, carcass characteristics, and meat composition of late-fattening Hanwoo steers. The steers (n = 40) were randomly divided into the four groups with 10 steers each: LP0 (lupin flake 0%), LP3 (lupin flake 3%), LP6 (lupin flake 6%), and LP9 (lupin flake 9%). The total digestible nutriant intake increased as the concentration of lupin increased (linear and quadratic effects; p < 0.05). The thiobarbituric acid-reactive substance content in the strip loins decreased as lupin flake supplementation levels increased (linear and quadratic effects; p < 0.05), while carnosine levels increased linearly (p < 0.05). As the lupin flake supplementation level increased, anserine and creatinine contents increased linearly and quadratically (p < 0.05). Similarly, adenosine triphosphate (ATP) and adenosine monophosphate (AMP) content increased with increasing lupin flake supplementation levels in linear and quadratic effects (p < 0.001). Palmitoleic acid content increased significantly with increasing lupin flake supplementation level (linear and quadratic effects; p < 0.05). The content of oleic acid in the strip loin was not significant, but the unsaturated fatty acid (UFA) (p < 0.05) and n-6/n-3 ratio (p < 0.05) increased. The results of this study indicated that although lupin flake supplementation did not markedly affect the growth, carcass characteristics, or meat composition of late-fattening Hanwoo steers, it exerted a positive effect on the flavor, taste profiles (anserine, creatinine, ATP, and AMP), hypotonicity (TBARS), and healthy meat production (UFA and n-6/n-3 ratio) related to beef.

Effect of microencapsulation of egg yolk immunoglobulin Y by sodium alginate/chitosan/sodium alginate on the growth performance, serum parameters, and intestinal health of broiler chickens.

OBJECTIVE: Egg yolk immunoglobulin (IgY) is an antibiotic alternative to prevent and fight intestinal pathogenic infections. This study aimed to investigate the effects of sodium alginate/chitosan/sodium alginate IgY microcapsules on the growth performance, serum parameters, and intestinal health of broiler chickens. METHODS: One-day-old broilers (Ross 308) were divided into five treatments, each with 10 replicates of five chickens. The dietary treatments were maintained for 28 days and consisted of a basal diet (NC), basal diet + 500 mg chlortetracycline/kg diet (CH), basal diet + 50 mg non-microencapsulated IgY/kg diet (NM), basal diet + 600 mg low levels microencapsulated IgY/kg diet (LM), and basal diet + 700 mg high levels microencapsulated IgY/kg diet (HM). RESULTS: Throughout the 28-day trial period, the NM, LM, HM, and CH groups increased average daily gain compared with the NC group (p<0.05), and the HM group reduced feed conversion ratio compared with the CH group (p<0.05). The LM and HM groups increased relative organ weights of thymus and spleen compared with the CH and NM groups (p<0.05). The HM group improved the duodenal, jejunal and ileum villi height (VH) and villus height to crypt depth ratio (VH:CD) compared with the CH and NM groups (p<0.05). Compared with the CH group, the HM group increased serum immunoglobulin (IgA), immunoglobulin G (IgG), superoxide dismutase, total antioxidant capacity, and glutathione peroxidase levels (p<0.05), and decreased serum malondialdehyde levels (p<0.05). Compared with the NC group, the NM, LM, HM, and CH groups reduced colonic Escherichia coli and Salmonella levels (p<0.05). and the HM group promoted the levels of lactic acid bacteria and bifidobacteria compared with the CH group (p<0.05). CONCLUSION: Microencapsulation could be considered as a way to improve the efficiency of IgY. The 700 mg high levels microencapsulated IgY/kg diet could potentially be used as an alternative to antibiotics to improve the immune performance and intestinal health, leading to better performance of broiler chickens.

Effect of Rumen Protected Methionine and α-Tocopherol on Growth Performance, Carcass Characteristics, and Meat Composition of Late Fattening Hanwoo Steer in High-Temperature Seasons.

This study was conducted to investigate the effects of rumen-protected methionine and α-tocopherol (RPMT) on growth performance, carcass characteristics, and meat composition of late fattening Hanwoo steers in high-temperature seasons. Fourteen steers were randomly assigned to one of two diets; control (commercial concentrate) and treatment (commercial concentrate + 20 g of RPMT). Average daily gain was 34% higher in the treatment group than in the control group; however, there was no significant difference due to the small number under investigation. Feed conversion ratio was lower in the treatment group than in the control group (p < 0.05). Supplementation of RPMT had little effect on the fatty acid composition of longissimus muscle. Metmyoglobin in the longissimus muscle was significantly lower in treatment group compared to the control group at the ninth day of storage (p < 0.05). The redness of the longissimus muscle was higher in the treatment group than in the control group on day 9 of storage (p < 0.01). Thus, the results suggest that RPMT have positive effects on growth performance, and Commission Internationale de l'Eclairage color stability in the longissimus muscle of late fattening Hanwoo steers in high-temperature seasons.

A study on the optimal thickness of corn flakes produced by using the pressurized steam chamber.

This study was conducted to evaluate the effect of the thickness of corn flakes produced by pressurized steam chamber (PSC) on rumen fermentation characteristics and nutrient degradability in Hanwoo and Holstein cows. Corn flakes were treated by PSC, in three groups based on corn flake thickness: < 2.5 mm (T1), 2.5-3.0 mm (T2), and > 3.0 mm (T3). Corn flake thickness significantly influenced pH (p < 0.01) and propionate concentration (p < 0.05) and slightly but not significantly influenced acetate, butyrate, and total-volatile fatty acids (T-VFA) concentrations. The dry matter (DM) degradability increased significantly with a reduction in corn flake thickness (p < 0.01), being significantly greater in T1 and T2 than T3 groups (p < 0.01) and similar between T1 and T2 groups throughout whole incubation time. Also, starch degradability was the lowest in T3 groups than others (p < 0.01). Thus, the present results showed that considering the production efficiency and economic feasibility, the optimal thickness of corn flakes produced in a PSC is recommended to be 2.5-3.0 mm.

Expression and purification of His-tagged flavonol synthase of Camellia sinensis from Escherichia coli.

Flavonols, a class of bioactive polyphenols present in plants, are the products of flavonol desaturation catalyzed by flavonol synthase (FLS). We cloned the cDNA coding for the enzyme FLS from Camellia sinensis (CsFLS) by end-to-end PCR followed by 5'- and 3'-RACE. The putative CsFLS had 333 amino acid residues, displayed identities to the FLSs of Arabidopsis and Ginkgo of 53% and 52.5%, respectively, and contained several conserved elements found in the 2-oxoglutarate-Fe(II)-dioxygenase superfamily. The cDNA of CsFLS was subcloned into pET28a(+) and introduced into Escherichia coli (BL21-CodonPlus-RIL). Induction with 0.1mM IPTG at low temperature (20 degrees C) led to higher amounts of CsFLS in the soluble fraction than induction at 30 degrees C. The enzyme aggregated into inclusion bodies could be rescued by denaturation with 6M urea and purification with a His. Bind purification kit. The purified protein was desalted by Amicon Ultra-15 centrifugal filter unit, and the His-tag was removed with thrombin. The finally purified protein was assayed with dihydroquercetin as substrate and the products were analyzed by HPLC. The addition of FeSO(4) to the buffers used in the CsFLS purification significantly increased the recovery of active enzyme. The CsFLS obtained in this study was found to have higher specific activity and lower K(m) than previously reported FLSs.