Rumen fermentation, methane concentration, and blood metabolites of cattle receiving dietetical phytobiotic and cobalt (II) chloride

Background and Aim

Ensuring the genetic potential of ruminants through nutrition studies using medicinal plants and trace element metals is an urgent task. This study aimed to study the effect of Artemisia absinthium L. (Asteraceae) herb plant separately and in combination with cobalt (II) chloride (CoCl₂) chelate compounds on the course of metabolic processes in the rumen, methane concentration, and biochemical blood parameters in bulls.

Materials and Methods

Control group (BD: Basal diet); experimental Group I - BD + A. absinthium herb at a dose of 2.0 g/kg dry matter (DM), experimental Group II - BD + A. absinthium herb at a dose of 2.0 g/kg DM + CoCl₂ (1.5 mg/kg), and experimental Group III - BD + CoCl₂ were set (1.5 mg/kg). The study was conducted on 16 beef bulls (Kazakh white-headed breed) aged 13-14 months, with an average live weight of 330-335 kg. Enzymatic processes in the rumen were studied, including the level of volatile fatty acids (using the gas chromatography method), nitrogen and its fractions (using the Kjeldahl method), methane concentration, and morphological and biochemical blood composition.

Results

There was a decrease in the concentration of acetic acid in experimental group I (15.9%) (p < 0.05) and in the III group (60.3%) and propionic acid in all experimental groups by 5.6%-47.3% (p < 0.05). Feeding A. absinthium herb as part of the diet of experimental Group I contributed to a decrease in methane concentration by 17.8% (p = 0.05) and the lowest methane concentration was noted for experimental Group III. It was less than in control by 59.1% (p < 0.05). An increase in the concentration of glucose, total protein, and creatinine was found in the experimental groups (p < 0.05). The digestibility of organic matter (3.5%), crude fiber (3.6%), and hemicellulose (11.0%) increased with the feeding of A. absinthium herb.

Conclusion

Thus, using biocomplexes based on A. absinthium herb and CoCl₂ do not harm the rumen fermentation of cattle. Still, further microbiome studies are required to evaluate the effects of A. absinthium on cattle properly.

The Effects of Non-Fiber Carbohydrate Content and Forage Type on Rumen Microbiome of Dairy Cows

Simple Summary

For sustainable development in the dairy industry, crop by-products play an important role, especially in areas that lack pasture and are not suitable for intensive cereal-adapted production (i.e., diets containing high amounts of cereal grains). However, feeding crop by-products usually lowers milk production in dairy cows due to their poor nutrient quality. In a previous study, we have demonstrated that non-fiber carbohydrate content (NFC) is a major limiting factor for the utilization of diets based on corn stover (CS). Although the higher abundance of easily fermentable energy in NFC and forage type can influence the synthesis of VFAs and MCP in the rumen and higher NFC content or high quality forages normally have a positive influence on the lactation performance of dairy cows, the underlying microbial mechanisms and potential effects on milk production are under-investigated to date. Here, we examined microbial composition and predicted the metabolism from cows fed CS-based diets with either high levels of NFC (H-NFC), or low levels of NFC (L-NFC). Control cows were fed an alfalfa-based diet (AH). Our results show that, supplementation of the CS-based diet with additional NFC increased amino acid biosynthesis in rumen microbiota in dairy cattle, and thus resulted in better nitrogen conversion. However, lower levels of fibrolytic capacity may limit dry matter intake of cows fed H-NFC and may prevent increased milk yield.

Abstract

The main objective of our current study was evaluating the effects of NFC supplementation and forage type on rumen microbiota and metabolism, by comparing microbial structures and composition among samples collected from cows fed AH (alfalfa-based diet), H-NFC (CS-based diet with high NFC) and L-NFC (CS-based diet with low NFC) diets. Our results show that microbial communities were structurally different but functionally similar among groups. When compared with L-HFC, NFC increased the population of Treponema, Ruminobacter, Selenomonas and Succinimonas that were negatively correlated with ruminal NH3-N, and urea nitrogen in blood, milk and urine, as well as significantly increasing the number of genes involved in amino acid biosynthesis. However, when compared to the AH group, H-NFC showed a higher abundance of bacteria relating to starch degradation and lactate production, but a lower abundance of bacteria utilizing pectin and other soluble fibers. This may lead to a slower proliferation of lignocellulose bacteria, such as Ruminococcus, Marvinbryantia and Syntrophococcus. Lower fibrolytic capacity in the rumen may reduce rumen rotation rate and may limit dry matter intake and milk yield in cows fed H-NFC. The enzyme activity assays further confirmed that cellulase and xylanase activity in AH were significantly higher than H-NFC. In addition, the lower cobalt content in Gramineae plants compared to legumes, might have led to the significantly down-regulated microbial genes involved in vitamin B12 biosynthesis in H-NFC compared to AH. A lower dietary supply with vitamin B12 may restrict the synthesis of milk lactose, one of the key factors influencing milk yield. In conclusion, supplementation of a CS-based diet with additional NFC was beneficial for nitrogen conversion by increasing the activity of amino acid biosynthesis in rumen microbiota in dairy cattle. However, lower levels of fibrolytic capacity may limit dry matter intake of cows fed H-NFC and may prevent increased milk yield.

Relationship between Vitamin B12 and Cobalt Metabolism in Domestic Ruminant: An Update

Cobalt, as a trace element, is essential for rumen microorganisms for the formation of vitamin B12. In the metabolism of mammals, vitamin B12 is an essential part of two enzymatic systems involved in multiple metabolic reactions, such as in the metabolism of carbohydrates, lipids, some amino acids and DNA. Adenosylcobalamin and methylcobalamin are coenzymes of methylmalonyl coenzyme A (CoA) mutase and methionine synthetase and are essential for obtaining energy through ruminal metabolism. Signs of cobalt deficiency range from hyporexia, reduced growth and weight loss to liver steatosis, anemia, impaired immune function, impaired reproductive function and even death. Cobalt status in ruminant animals can be assessed by direct measurement of blood or tissue concentrations of cobalt or vitamin B12, as well as the level of methylmalonic acid, homocysteine or transcobalamin in blood; methylmalonic acid in urine; some variables hematological; food consumption or growth of animals. In general, it is assumed that the requirement for cobalt (Co) is expressed around 0.11 ppm (mg/kg) in the dry matter (DM) diet; current recommendations seem to advise increasing Co supplementation and placing it around 0.20 mg Co/kg DM. Although there is no unanimous criterion about milk production, fattening or reproductive rates in response to increased supplementation with Co, in some investigations, when the total Co of the diet was approximately 1 to 1.3 ppm (mg/kg), maximum responses were observed in the milk production.

Evaluation of cobalt as a performance enhancing drug (PED) in racehorses

Cobalt is a required trace element in animals, but administration in excess is considered dangerous and potentially performance enhancing in equine athletes. This study seeks to determine if cobalt may actually act as a performance enhancing drug (PED) by altering biochemical parameters related to red blood cell production as well as markers of aerobic and anaerobic exercise performance. In addition, for adequate regulation of naturally occurring substances, such as cobalt, its distribution among the population must be defined. In order to identify this distribution, plasma Cobalt was determined from 245 Standardbred horses with no cobalt supplementation from farms in New York and New Jersey, including horses at the Rutgers University Equine Science Center. Samples were analysed by Inductively Coupled Plasma Mass Spectrometry. Seven healthy, race fit Standardbreds (4 geldings, 3 mares, age: 5±3 years, ~500 kg) were used for the PED experiment. An incremental graded exercise test (GXT) to measure maximal aerobic capacity (V̇O2max) and markers of performance, measurement of plasma volume and blood volume as well as the measurement of lactate, erythropoietin (EPO), and various blood haematological factors were determined 7 days prior to cobalt administration. Each horse was administered a sterile solution of cobalt salts (50 mg of elemental Co as CoCl2 in 10 ml of saline, IV) at 9 AM on three consecutive days via the jugular vein. Blood samples were obtained from the contralateral jugular vein before and at 1, 2, 4 and 24 h after administration. Plasma and blood volume were measured one day after the last dose of cobalt, and a post administration GXT was performed the next day. Horses were observed for signs of adverse effects of the cobalt administration (agitation, sweating, increased respiration, etc.). Plasma cobalt concentration increased from a pre-administration mean of 1.6±0.6 to 369±28 μg/l following 3 doses of the cobalt solution (P<0.05). This Co concentration was unaccompanied by changes in aerobic or anaerobic performance, plasma EPO concentration, plasma volume, resting blood volume, total blood volume, or estimated red blood cell volume (P>0.05). There were no observed adverse effects.