Increasing the number of plant species in a pasture improves the mineral balance of grazing beef cattle

Effects of sources and levels of dietary supplementary manganese on growing yak's in vitro rumen fermentation

Introduction

Manganese (Mn) is an essential trace element for livestock, but little is known about the optimal Mn source and level for yak.

Methods

To improve yak's feeding standards, a 48-h in vitro study was designed to examine the effect of supplementary Mn sources including Mn sulfate (MnSO₄), Mn chloride (MnCl₂), and Mn methionine (Met-Mn) at five Mn levels, namely 35 mg/kg, 40 mg/kg, 50 mg/kg, 60 mg/kg, and 70 mg/kg dry matter (includes Mn in substrates), on yak's rumen fermentation.

Results

Results showed that Met-Mn groups showed higher acetate (p < 0.05), propionate, total volatile fatty acids (p < 0.05) levels, ammonia nitrogen concentration (p < 0.05), dry matter digestibility (DMD), and amylase activities (p < 0.05) compared to MnSO4 and MnCl2 groups. DMD (p < 0.05), amylase activities, and trypsin activities (p < 0.05) all increased firstly and then decreased with the increase of Mn level and reached high values at 40-50 mg/kg Mn levels. Cellulase activities showed high values (p < 0.05) at 50-70 mg/kg Mn levels. Microbial protein contents (p < 0.05) and lipase activities of Mn-Met groups were higher than those of MnSO4 and MnCl2 groups at 40-50 mg/kg Mn levels.

Discussion

Therefore, Mn-met was the best Mn source, and 40 to 50 mg/kg was the best Mn level for rumen fermentation of yaks.

Creating a Design Framework to Diagnose and Enhance Grassland Health under Pastoral Livestock Production Systems

Grasslands and ecosystem services are under threat due to common practices adopted by modern livestock farming systems. Design theory has been an alternative to promote changes and develop more sustainable strategies that allow pastoral livestock production systems to evolve continually within grasslands by enhancing their health and enabling the continuous delivery of multiple ecosystem services. To create a design framework to design alternative and more sustainable pastoral livestock production systems, a better comprehension of grassland complexity and dynamism for a diagnostic assessment of its health is needed, from which the systems thinking theory could be an important approach. By using systems thinking theory, the key components of grasslands-soil, plant, ruminant-can be reviewed and better understood from a holistic perspective. The description of soil, plant and ruminant individually is already complex itself, so understanding these components, their interactions, their response to grazing management and herbivory and how they contribute to grassland health under different climatic and topographic conditions is paramount to designing more sustainable pastoral livestock production systems. Therefore, by taking a systems thinking approach, we aim to review the literature to better understand the role of soil, plant, and ruminant on grassland health to build a design framework to diagnose and enhance grassland health under pastoral livestock production systems.

Effects of Grazing in a Sown Pasture with Forestland on the Health of Japanese Black Cows as Evaluated by Multiple Indicators

The objective of the present study was to evaluate the effects of extensive grazingin a sown pasture with forestland on the health of beef cows by measuring multiple indicators. Ten Japanese Black beef cows were used in this experiment. Five of the ten cows were grazed for two months on a 1.8 ha field. The remaining cows were fed under confinement conditions. Behavioral assessments showed that grazing increased sternum lying with rumination of the cows. The grazing cows did not show any abnormal behaviors. There was a tendency for the numbers of red blood cells and lymphocytes to be lower in grazing cows than in confined cows, whereas the number of neutrophils in grazing cows was significantly higher than that in confined cows. In addition, grazing cows had a higher total antioxidant capacity and glutathione peroxidase activity than confined cows. These results suggest that extensive grazing in a sown pasture with forestland increases natural behaviors, decreases circulating red blood cells and lymphocytes and enhances neutrophil circulation, antioxidant enzyme activity, and antioxidant capacity.

Mineral Nutritional Status of Yaks (Bos Grunniens) Grazing on the Qinghai-Tibetan Plateau

Minerals are essentially important for supporting livestock's health, as well as productivity. This study aimed to investigate the mineral status of yaks (Bos grunniens) grazing on the Qinghai-Tibetan Plateau (QTP) and the relationship between macro and micro mineral nutrients among soil, forages, and blood in four counties of the QTP. The soil samples (n = 320), forages (n = 320), and blood serum (n = 320) were collected from four randomly selected yak farms in each location during July (warm season) and December (cold season), and were analyzed for macro minerals (P, Ca, K, Mg, Na) and micro minerals (Fe, Mn, Zn, Cu, Se). Based on this study, both of the macro and micro minerals were very variable between seasons and many of the macro and micro minerals, such as P, Mg, K, S, Na, Se, and Cu, were found to be below the requirement level for yaks in all four counties. It was significantly shown that the concentrations of both macro and micro minerals in soil and forages influenced the serum concentration of minerals, showing the deficient status of yaks.

Reducing mineral usage in feedlot diets for Nellore cattle: I. Impacts of calcium, phosphorus, copper, manganese, and zinc contents on microbial efficiency and ruminal, intestinal, and total digestibility of dietary constituents

This study evaluated intake, microbial efficiency, and ruminal, small and large intestinal, and total digestibility of DM, OM, CP, and NDF, as well as availability of Ca, P, Mg, Na, K, Cu, Mn, and Zn in Zebu cattle fed with or without supplemental sources of Ca and P or a micromineral premix. Five rumen- and ileum-cannulated Nellore bulls (BW = 200 ± 10.5 kg; 9 mo) were used in the experiment, distributed in a 5 × 5 Latin square design. The experiment was developed in a 2 × 2 + 1 factorial design to measure the effects of mineral supplementation on intake, digestibility, and site of nutrient absorption. The factors consisted of 2 Ca and P levels (macromineral factor; CaP+ or CaP-) and 2 microminerals levels (micromineral factor; CuMnZn+ or CuMnZn-). In addition, a treatment with alimentary restriction (REST) was evaluated at 1.7% of BW. Nutrient fluxes were measured in the omasum and ileum, in addition to intake and fecal excretion. Microbial efficiency was estimated using purine derivative excretion. Dry matter, OM, NDF, CP intake, and total digestibility were not affected ( ≥ 0.058) by the absence of Ca, P, Cu, Mn, and Zn supplementation. Intake of Ca, P, and Mg were reduced ( < 0.01) by CaP-. The absence of CuMnZn reduced ( < 0.01) Cu, Mn, and Zn intake. Ruminal recycling of P, Na, and K is significant for increasing the influx of these minerals to the digestive tract; however, influences of treatments were not observed. The small and large intestines contributed to mineral absorption in different proportions ( < 0.05), according to minerals and treatments. Because of the similarity ( > 0.05) of OM, NDF, and CP digestion sites and coefficients, we assume that omitting supplemental sources of Ca, P, Cu, Mn, and Zn may be an option in raising cattle on feedlots. If supplementation is viable, knowledge about the specific absorption site of each mineral could positively impact choices about the supplemental source.