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Wang F.,China Agricultural University | Li S.L.,China Agricultural University | Xin J.,China Agricultural University | Wang Y.J.,China Agricultural University | And 3 more authors.
Journal of Dairy Science | Year: 2012

The objective of this study was to investigate the effects of methionine hydroxy Cu [(HMTBA)2-Cu] supplementation on lactation performance, nutrient digestibility, and blood biochemical parameters in lactating cows. Thirty lactating Holstein cows were assigned to 1 of 3 treatments in a randomized block design: (1) Cu sulfate only (S): 12mg of Cu provided by CuSO4 per kilogram of concentrate; (2) Cu sulfate and (HMTBA)2-Cu (SM): 6mg of Cu provided by CuSO4 and 6mg of Cu provided by (HMTBA)2-Cu per kilogram of concentrate; or (3) (HMTBA)2-Cu only (M): 12mg of Cu provided by (HMTBA)2-Cu per kilogram of concentrate. The level of dietary Cu was determined according to the NRC (2001) requirement. This experiment lasted for 120 d, with the first 20 d for adaptation and with sample and data collection beginning on d 21. The milk yield and 4% fat-corrected milk yield of cows in the SM treatment tended to increase compared with those in the S and M treatments. Cows fed SM also tended to have higher NDF and ADF apparent digestibility values than did cows fed S or M. Plasma Cu concentration significantly increased for the SM treatment compared with the S and M treatments. Cows fed S had higher plasma K concentration than did cows in the other 2 treatments. In conclusion, replacing one-half of the dietary Cu sulfate with (HMTBA)2-Cu increased plasma Cu concentration and tended to improve the neutral and acid detergent fiber apparent digestibility values and the lactation performance of lactating dairy cattle. © 2012 American Dairy Science Association. Source

Wang F.,China Agricultural University | Wang L.,China Agricultural University | Li S.,China Agricultural University | Wang Y.,Novus International Inc. | And 2 more authors.
Asian Journal of Animal and Veterinary Advances | Year: 2011

Thirty Holstein cows (10 cows per treatment) were blocked according to calving date, milk yield and party and randomly assigned to a study to determine the effect of manganese (Mn) sources on lactating cows. Treatments were (1) all Mn (14 ppm) supplied by sulfate (S), (2) Mn sulfate (MnSO 4) and methionine hydroxyl manganese (Mn-(HMTBA) 2) contributed half of the dietary Mn (SM) or (3) all Mn supplied by (Mn-(HMTBA) 2) (M). The average 4% Fat-corrected Milk (FCM) yield and fat yield of cows supplied with M dietary were significantly higher than the cows fed with SM and the S (p<0.05). The average lactose rate of SM was significantly lower than S and M (p<0.05). Numerically, the apparent digestibility of organic matter, crude protein, crude fat and acid detergent fiber of S were the lowest but no significant difference were found between groups (p>0.05). Significant increases was observed for serum High-density lipoprotein cholesterol concentration of M compared with S and SM (p<0.05). The average detectable follicle numbers and ovarian score for cows of M was generally lower than cows of SM and S but no significant difference was observed (p>0.10). The present study suggested that replacing a portion of dietary Mn sulfate with Mn-(HMTBA) 2 during the peak-and mid-lactation periods will improve the lipid metabolism and milk fat secretion; however, the follicular development may be hampered. © 2011 Academic Journals Inc. Source

Sun H.,Zhejiang University | Sun H.,University of Jinan | Wu Y.M.,Zhejiang University | Wang Y.M.,Novus International Research Center | And 2 more authors.
Asian-Australasian Journal of Animal Sciences | Year: 2014

An in vitro experiment was conducted to evaluate the effects of Aspergillus oryzae culture (AOC) and 2-hydroxy-4-(methylthio)-butanoic acid (HMB) on rumen fermentation and microbial populations between different roughage sources. Two roughage sources (Chinese wild rye [CWR] vs corn silage [CS]) were assigned in a 2×3 factorial arrangement with HMB (0 or 15 mg) and AOC (0, 3, or 6 mg). Gas production (GP), microbial protein (MCP) and total volatile fatty acid (VFA) were increased in response to addition of HMB and AOC (p<0.01) for the two roughages. The HMB and AOC showed inconsistent effects on ammonia-N with different substrates. For CWR, neither HMB nor AOC had significant effect on molar proportion of individual VFA. For CS, acetate was increased (p = 0.02) and butyrate was decreased (p<0.01) by adding HMB and AOC. Increase of propionate was only occurred with AOC (p<0.01). Populations of protozoa (p≤0.03) and fungi (p≤0.02) of CWR were differently influenced by HMB and AOC. Percentages of F. succinogenes, R. albus, and R. flavefaciens (p<0.01) increased when AOC was added to CWR. For CS, HMB decreased the protozoa population (p = 0.01) and increased the populations of F. succinogenes and R. albus (p≤0.03). Populations of fungi, F. succinogenes (p = 0.02) and R. flavefacien (p = 0.03) were increased by adding AOC. The HMB×AOC interactions were noted in MCP, fungi and R. flavefacien for CWR and GP, ammonia-N, MCP, total VFA, propionate, acetate/propionate (A/P) and R. albus for CS. It is inferred that addition of HMB and AOC could influence rumen fermentation of forages by increasing the number of rumen microbes. Copyright © 2014 by Asian-Australasian Journal of Animal Sciences. Source

Wang Y.M.,Zhejiang University | Wang J.H.,Zhejiang University | Wang C.,Zhejiang University | Chen B.,Zhejiang University | And 4 more authors.
Journal of Dairy Science | Year: 2010

The objective of the study was to evaluate the effect of diets supplemented with fatty acids of different degrees of saturation, in the absence or presence of an antioxidant (AOX; Agrado Plus, Novus International Inc., St. Charles, MO), on dairy cow lactation performance. Calcium salts of long-chain fatty acids were supplemented as a source of lower saturation fatty acid, and a palm acid product was supplemented as the higher saturation fatty acid source. Sixty early-lactation Chinese Holstein cows (100±23 d in milk) were randomly allocated to 4 dietary treatments in a 2 × 2 factorial design: (1) lower saturation fatty acid (LS), (2) LS and AOX, (3) higher saturation fatty acid (HS), and (4) HS and AOX. The Ca salts of long-chain fatty acids and palm acid product were supplied at 1.8 and 1.5% on a dry matter basis, respectively, to form isoenergetic diets. The AOX was added at 0.025% in the ration. The experiment lasted 9 wk, including 1 wk for adaptation. Lactation performance was recorded and milk was sampled and analyzed weekly. Blood samples were taken from the coccygeal vein to determine metabolism parameters on d 16, 36, and 56 during the experiment. Neither fatty acid type nor AOX supplementation showed a significant effect on dry matter intake during the study. Milk yield was lower in the LS-fed cows compared with the cows fed HS. Milk fat and milk protein concentrations were not affected by fatty acid type or AOX supplementation. Adding AOX increased the yield of milk in the LS-fed cows, but did not affect those fed HS. Activity of plasma superoxide dismutase was significantly lower, plasma glucose tended to be lower, and plasma malondialdehyde was higher in the LS-fed animals compared with those fed HS. Addition of AOX decreased both plasma nonesterified fatty acids and hydrogen peroxide contents and increased total antioxidant capacity across the fatty acid types. Plasma β-hydroxybutyrate was not affected by fatty acid type or AOX treatment. Cows fed LS had higher cis-9C18:1 and trans-10, cis-12C18:2 in milk at the expense of C18:0, whereas AOX addition increased milk cis-9C18:1 at the expense of milk C12:0, C16:0, and trans-10, cis-12C18:2. It is inferred that feeding LS resulted in inferior lactation performance, whereas addition of antioxidant partially alleviated these negative effects. © 2010 American Dairy Science Association. Source

Wang Y.M.,Zhejiang University | Wang J.H.,Zhejiang University | Wang C.,Zhejiang University | Wang J.K.,Zhejiang University | And 6 more authors.
Asian-Australasian Journal of Animal Sciences | Year: 2010

This study was conducted to evaluate the effect of dietary antioxidant and energy density on performance and antioxidative status in transition cows. Forty cows were randomly allocated to 4 dietary treatments in a 2×2 factorial design. High or low energy density diets (1.43 or 1.28 Meal NEL/kg DM, respectively) were formulated with or without antioxidant (AOX, a dry granular blend of ethoxyquin and tertiary-butylhydroquinone; 0 or 5 g/cow per d). These diets were fed to cows for 21 days pre-partum. During the post-partum period, all cows were fed the same lactation diets, and AOX treatment followed as for the pre-partum period. Feeding a high energy diet depressed the DMI, milk yield, and 4% fat-corrected milk (FCM) of cows. However, AOX inclusion in the diet improved the milk and 4% FCM yields. There was an interaction of energy density by AOX on milk protein, milk fat and total solids contents. Feeding a high energy diet pre-partum increased plasma glucose and β-hydroxybutyrate, whereas dietary AOX decreased plasma β-hydroxybutyrate value during the transition period. There were also interactions between time and treatment for plasma glutathione peroxidase activity and malondialdehyde content during the study. Cows fed high energy diets pre-partum had higher plasma glutathione peroxidase activity 3 days prior to parturition, compared with those on low energy diets. Inclusion of AOX in diets decreased plasma glutathione peroxidase activity in cows 3 and 10 days pre-partum. Addition of AOX significantly decreased malondialdehyde values at calving. Energy density induced marginal changes in fatty acid composition in the erythrocyte membrane 3 days post-partum, while AOX only significantly increased cis-9, trans-11 conjugated linoleic acid composition. The increase in fluidity of the erythrocyte membrane was only observed in the high energy treatment. It is suggested that a diet containing high energy density pre-partum may negatively affect the anti-oxidative status, DMI and subsequent performance. Addition of AOX may improve the anti-oxidative status and reduce plasma β-hydroxybutyrate, eventually resulting in improved lactation performance; the response to AOX addition was more pronounced on the high energy diet. Source

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