Effects of Zinc and Sodium Monensin on Ruminal Degradation of Lysine-HCl and Liquid 2-Hydroxy-4-Methylthiobutanoic Acid,

Abstract

Four nonlactating, mature, Holstein cows were fitted with ruminal cannula and used in a 4 x 4 Latin square-designed experiment to evaluate the impact of supplemental Zn and monensin on ruminal degradation of Lys and liquid 2-hydroxy-4-methylthiobutanoic acid (HMB). Cows were fed 4.54 kg (as fed) of alfalfa hay top-dressed with 4.54 kg (as fed) concentrate once daily. Concentrates were formulated to provide 0 or 500 mg/kg of Zn as ZnSO4 and 0 or 40 mg/kg of monensin in the total diet. Zinc supplementation provided approximately 22-fold greater dietary Zn than estimated by NRC requirements. On d 14 of each period, cows were dosed via the rumen cannula with 50 g of HMB and 100 g of Lys-HCl, and the concentrations of Lys and HMB were monitored every 0.5 h for 8 h. Supplemental Zn tended to decrease the proportion of acetate in ruminal fluid postfeeding and increased the proportion of propionate in ruminal fluid postfeeding. Supplemental Zn increased mean fluid passage rate from the rumen. Monensin decreased the proportion of acetate and increased the mean proportion of propionate in ruminal fluid, resulting in a decrease in the ratio of acetate to propionate. Monensin also increased the mean fluid passage rate from the rumen. Neither Zn nor monensin affected the apparent rate of ruminal disappearance of HMB or Lys. However, Zn and monensin interacted to alter the ruminal degradability of free Lys but not HMB. These data indicate that Zn and monensin may interact to alter ruminal degradability of free amino acids.

Effects of Flavomycin on Ruminal Fermentation, <em>In Situ</em> Degradability and <em>In Vivo</em> Digestibility in Bovine Fed Sugarcane Diets

“…These authors observed that this product, despite frequently decreased protein degradation in rumen, caused variable impact on DM or CP digestibility, based on basal diet used. According to Bateman et al (2004), if an increase in microbial efficiency occurs due to monensin addition associated with an increase in aminoacids flux to small intestine, an improvement in protein status of the animal could occur. Another point to mention is that, in the present trial, the apparent digestibility was evaluated not the true digestibility.…”

Effects of dietary addition of zinc and(or) monensin on performance, rumen fermentation and digesta kinetics in beef cattle

“…It is generally accepted that a faster passage rate and an increased turnover time would improve microbial efficiency due to a faster change of rumen population and better supply of microbial protein to the lower tract. Bateman II et al (2004) found that both Zn (500 mg kg -1 ) and monensin (40 mg kg -1 ) increased the fluid passage rate when a 50:50 alfalfa:concentrate diet was fed to Holstein cannulated steers. However, «the alfalfa hay was topdressed with the concentrate» (ground corn + soybean meal + minerals) and fed once daily, while in our experiment, for a similar diet, the supplement was mixed and fed with the morning meal.…”

“…Alfalfa (Medicago sativa L.) hay and barley (Hordeum vulgare L.) grain are common ingredients used for growingfinishing diets in beef cattle. Animal performance on this type of diet could be increased by the addition of Zn in the diet (Arelovich et al, 2000;Faixova and Faix, 2002;Bateman II et al, 2004). One of the advantages of using Zn as an additive is that various inorganic Zn salts can be easily obtained in the market, and usually they have a lower cost when compared to monensin or similar feed additives.…”

“…Therefore, feed eff iciency and beef production could be improved by Zn inclusion in cattle diets. It was also shown that when administered at over 20 times the daily NRC (2000) requirement, Zn could increase the concentration of rumen propionate (Arelovich et al, 2000) and decrease the acetate:propionate ratio (Bateman II et al, 2004).…”

ZnO Nanopartiküllerinin Bazı Hayvan ve Bitki Protein Kaynaklarının İn Vitro Gaz Üretimi Üzerine Etkisi

“…Effect of ZnO Nanoparticles on ... Addition Zn to ruminant diet to more than needed, change their rumen fermentation and increase the ratio of propionic acid and decreases acetate to propionate ratio and it is concluded that increases the energy value of the diet [5] . Because of the unique characteristics of ZnO nanoparticles, these materials used in various industries including food, pharmaceutical, rubber, electronics and packaging and even as feed additives [6] .…”