Ruminal Fermentation Patterns Research Articles

Effects of low-quality forage and starter protein content in starter diet of young calves on growth performance, rumen fermentation, and urinary purine derivatives.

Feeding low-quality forage (LQF) has been evaluated in mature ruminants and results show that it has been improved nitrogen utilization efficiency. The present study evaluated the interaction effect of feeding wheat straw as LQF (0 and 7.5%, DM basis) and starter protein level (20 vs. 24%, DM basis) on growth performance, ruminal fermentation, and microbial protein synthesis in Holstein dairy calves raised under moderate heat stress condition. Forty-eight 3-day old dairy calves (averaging 40.6 kg) were assigned in four experimental treatments as follow; 1) no LQF with 20% CP (NLQF-20CP), 2) no LQF with 24% CP (NLQF-24CP), 3) 7.5% LQF with 20% CP (LQF-20CP) and 4) 7.5% LQF and 24% CP (LQF-24CP). The calves were weaned on d 53 of age but the experiment extended until d 73 of age. Feeding LQF increased starter intake, average daily gain (tendency), ruminal acetate concentration, and improved fecal score of calves. The average daily gains before and after weaning were positively influenced with greater starter protein content. Hence, weaning and final BWs were improved when calves received greater CP content. In addition, greater starter CP content increased total ruminal volatile fatty acid concentration. With respect to the interaction effect between LQF feeding and starter protein content, the lower nitrogen excretion through urine was obtained for LQF-20CP diet among experimental treatments. The results of the current study showed that feeding LQF improved ruminal fermentation pattern and improved growth performance through increased starter intake. In addition, greater starter protein content is advisable during pre-weaning period for calves raised under mild heat stress condition. In conclusion, based on the results found in the current study, it can be suggested that feeding LQF for calves under heat stress condition can improve nitrogen utilization when dietary protein content is low. This can be opportunity to formulate starter diets with greater nitrogen utilization efficiency which is critical for accelerated growth programs at early stages of growth for young calves while calves raised under hot season condition.

Partially substituting alfalfa hay with hemp forage in the diet of goats improved feed efficiency, ruminal fermentation pattern and microbial profiles

The use of hemp as a forage source in livestock diets has been less studied because bioactive residues in animal tissues may pose a risk to consumers. This study investigated the effects of partial substitution of alfalfa hay (AH) with hemp forage (HF) in growing goat diets on growth performance, carcass traits, ruminal fermentation characteristics, rumen microbial communities, blood biochemistry, and antioxidant indices. Forty Xiangdong black goats with body weight (BW) 7.82 ± 0.57 kg (mean ± SD) were grouped by BW and randomly assigned into one of the four treatment diets (n = 10/treatment) in a completely randomized design. The goats were fed ad libitum total mixed rations containing 60% forage and 40% concentrate (DM basis). The diets included control (CON; 60% AH and 40% concentrate), 55% AH and 5% HF (HF5), 50% AH and 10% HF (HF10), and 40% AH and 20% HF (HF20). Increasing the substitution of HF for AH linearly decreased (P < 0.01) DM intake and improved feed conversion efficiency. However, final BW, average daily gain, carcass traits, meat quality, and most blood biochemistry indices did not differ among treatments. The ruminal NH3-N concentration and blood urine nitrogen linearly increased (P < 0.01) with increasing substitution rate of HF, whereas the total volatile fatty acids concentration quadratically changed (P < 0.01). Substitution of AH with HF had no effect on the diversity and richness of ruminal microbes, though it linearly decreased (P = 0.040) Prevotella_1 and linearly increased (P = 0.017) Rikenellaceae_RC9_gut_group. The cannabinoids and/or their metabolites were detected in both ruminal filtrates (8) and plasma (4), however, no detectable cannabinoid-related residues were observed in meat. These results indicate that the HF could be used to partially substitute AH in goat diets, whereas the effects vary between substitution rates of HF for AH. Although no cannabinoid-related residues were detected in meat, the presence of cannabinoids residues in blood warrants further study of HF feeding to confirm the cannabinoids residues are not present in the animal products.

Milk Yields and Milk Fat Composition Promoted by Pantothenate and Thiamine via Stimulating Nutrient Digestion and Fatty Acid Synthesis in Dairy Cows.

Considering the synergistic effect of pantothenate and thiamine on the regulation of energy metabolism, this study investigated the influences of coated calcium pantothenate (CCP) and coated thiamine (CT) on milk production and composition, nutrients digestion, and expressions of genes involved in fatty acids synthesis in mammary glands. Forty-four multiparous Chinese Holstein cows (2.8 ± 0.19 of parity, 772 ± 12.3 kg of body weight [BW], 65.8 ± 8.6 days in milk [DIM] and 35.3 ± 1.9 kg/d of milk production, mean ± SD) were blocked by parity, BW, DIM, and milk production, and they were allocated into one of four treatments in a 2 × 2 factorial block design. Additional CCP (0 mg/kg [CCP-] or 55 mg/kg dry matter [DM] of calcium pantothenate from CCP [CCP+]) and CT (0 g/kg [CT-] or 5.3 mg/kg DM of thiamine from CT [CT+]) were hand-mixed into the top one-third of total mixed ration. Both CCP and CT additives increased milk production, fat content, true protein, and lactose by promoting nutrient digestibility. The CCP or/and CT supplementation induced the elevation of C11:0, C12:0, C13:0, C14:0, C14:1, C15:0, C15:1, C16:00, C16:1, C24:00, C24:1 fatty acids, saturated fatty acid, and C4-16 fatty acid contents in milk fat; but it decreased C17-22 fatty acid content. Ruminal total VFA content was increased, but pH was decreased by both additives. The ruminal fermentation pattern was altered, and a tendency of acetate formation was implied by the increased acetate-to-propionate ratio after both additives' supplementation. The expressions of PPARγ, SREBPF1, ACACA, FASN, SCD, and FABP3 mRNAs were enhanced by CCP or CT addition, but the relative expression of LPL mRNA was upregulated by CT addition only. Additionally, blood glucose, triglyceride, insulin-like growth factor-1, and total antioxidant capacity were promoted by both additives. The combination of CCP and CT more effectively increased the ruminal total VFA concentration, the acetate to propionate ratio, and blood glucose level, and decreased ammoniacal nitrogen concentration than that achieved by CCP or CT alone. The results suggested that CCP and CT supplementation stimulated lactation performance by promoting nutrient digestion and fatty acid synthesis in the mammary glands.

Candida tropicalis as a novel dietary additive to reduce methane emissions and nitrogen excretion in sheep.

The goal of this study was to investigate Candida tropicalis as a kind of environmentally friendly dietary additive to manipulate ruminal fermentation patterns, reduce methane emissions and nitrogen excretion, and to screen the appropriate dose for sheep. Twenty-four Dorper × thin-tailed Han crossbred ewes (51.12kg ± 2.23kg BW) were selected and randomly divided into four groups which were fed Candida tropicalis at dose of 0 (control), 4 × 108 (low dose), 4 × 109 (medium dose), and 4 × 1010 (high dose) colony-forming units (CFU)/d per head, respectively. The experiment lasted 33days with 21days for adaptation and 12days for nutrient digestibility trial and respiratory gases sampling. The results showed that nutrients intake was not affected by Candida tropicalis supplementation (P > 0.05), whereas apparent digestibility of nutrients significantly increased compared with the control group (P < 0.05). Nitrogen and energy utilization increased with Candida tropicalis supplementation (P < 0.05). Compared with the ewes of the control group, rumen fluid pH and NH3-N concentration were not affected (P > 0.05), whereas total volatile fatty acid concentration and molar proportion of propionate were greater (P < 0.05), and molar proportion of acetate and the ratio of acetate to propionate were less (P < 0.05) when the ewes were fed Candida tropicalis. Daily total CH4 production (L/d) and CH4 emissions yield (L/d of CH4 per kg of dry matter intake, metabolic weight, or digestibility dry matter intake) were decreased at the low dose group (P < 0.05). The abundance of total bacteria, methanogen, and protozoa in rumen fluid was significantly higher at medium dose and high dose of Candida tropicalis supplementation (P < 0.05) compared with low dose and the control group. In summary, Candida tropicalis supplementation has a potential to reduce CH4 emissions and nitrogen excretion, and the optimal dose should be 4 × 108CFU/d per head.

Shortening the adaptation of Nellore cattle to high-concentrate diets using only virginiamycin as sole feed additive negatively impacts ruminal fermentation and nutrient utilization.

Feedlot cattle are usually adapted to high-concentrate diets containing sodium monensin (MON) in more than 14 days. However, considering that the dry matter intake DMI is usually lower during adaptation when compared to the finishing period, the use of MON during adaptation may decrease even further the DMI, and virginiamycin (VM) may be an alternative. This study was designed to investigate the effects of shortening the adaptation length from 14 to 9 or 6 days on ruminal metabolism, feeding behavior, and nutrient digestibility of Nellore cattle fed high-concentrate diets containing only VM as the sole feed additive. The experimental design was a 5 × 5 Latin square, where each period lasted 21 days. Five 17 mo-old Nellore yearling bulls were used (415 ± 22 kg of body weight), which were assigned to five treatments: (1) MON (30 mg/kg) and adaptation for 14 days; (2) MON (30 mg/kg) + VM (25 mg/kg) and adaptation for 14 days; (3) VM (25 mg/kg) and adaptation for 14 days; (4) VM (25 mg/kg) and adaptation for 9 days, and (5) VM (25 mg/kg) and adaptation for 6 days. A quadratic effect for adaptation length when only VM was fed was observed for mean pH (P = 0.03), duration of pH below 5.2 (P = 0.01) and 6.2 (P = 0.01), where cattle consuming VM adapted for 9 days had higher mean pH and shorter period of pH below 5.2 and 6.2. Cattle that consumed only MON had a lower concentration of butyrate (P = 0.02) and a higher concentration of propionate (P = 0.04) when compared to those consuming VM and adapted for 14 days. As the adaptation length decreased for animals consuming only VM, the rumen degradability of dry matter (P < 0.01), neutral detergent fiber (P < 0.01), and starch (P < 0.01) decreased; however, protozoa numbers of Entodinium and total protozoa increased. It is not recommended to shorten the adaptation length of these animals to either 6 or 9 days without negatively impacting nutrient disappearance and ruminal fermentation patterns.

Differential Diet and pH Effects on Ruminal Microbiota, Fermentation Pattern and Fatty Acid Hydrogenation in RUSITEC Continuous Cultures

The aim of this study was to distinguish effects due to diet composition from those triggered by ruminal pH on fermentation patterns and microbial profiles in a continuous culture system (RUSITEC). The study followed a 2 × 2 factorial design, with two diets varying in the proportions of forage and concentrate and two pH levels in the culture medium. RUSITEC fermenters were used to simulate rumen fermentation and feed digestibility, fermentation end-products, microbial protein synthesis, microbial community, and long-chain fatty acid profiles in the digesta were determined. Multivariate analyses were applied to summarize the overall results. High concentrate (34% cereal grain, 32% hay) diets were more digestible (p &lt; 0.05) than high forage (10% cereal grain, 78% hay) diets, resulting in a greater (p &lt; 0.05) formation of most fermentation end-products and microbial protein in the rumen. However, there were no significant (p &gt; 0.05) differences between diets in methane production. Ciliate protozoa, anaerobic fungi, some fibrolytic bacteria, hydrogenation of oleic acid, and relative proportion of conjugated linoleic acid were increased (p &lt; 0.05) with high forage diets. A decline in rumen pH from 6.8 to 6.4 decreased (p &lt; 0.05) feed digestibility, protein degradability, and the daily outputs of some fermentation end-products (gas, VFA, acetate, ammonia) but had no effect (p &gt; 0.05) on the synthesis of microbial protein, and on the output of methane, propionate, butyrate or lactate. Minor changes in microbial community profile or the fatty acid relative proportions were observed within this pH range. The overall multivariate analysis revealed a clear discrimination between high-concentrate and high-forage diets, with subtler and less-defined pH effects on ruminal fermentation and microbial communities.

Ruminal fermentation pattern of acidosis-induced cows fed either monensin or polyclonal antibodies preparation against several ruminal bacteria.

This study was designed to evaluate a spray-dried multivalent polyclonal antibody preparation (PAP) against lactate-producing bacteria as an alternative to monensin (MON) to control ruminal acidification. Holstein cows (677 ± 98 kg) fitted with ruminal cannulas were allocated in an incomplete Latin square design with two 20 days period. Cows were randomly assigned to control (CTL), PAP, or MON treatments. For each period, cows were fed a forage diet in the first 5 days (d-5 to d-1), composed of sugarcane, urea and a mineral supplement, followed by a 74% concentrate diet for 15 days (d 0 to d 14). There were no treatment main effects (P > 0.05) on dry matter intake (DMI) and microbial protein synthesis. However, there was a large peak (P < 0.01) of intake on d 0 (18.29 kg), followed by a large decline on d 1 (3.67 kg). From d2, DMI showed an increasing pattern (8.34 kg) and stabilized around d 8 (12.96 kg). Higher mean pH was measured (P < 0.01) in cattle-fed MON (6.06 vs. PAP = 5.89 and CTL = 5.91). The ruminal NH3-N concentration of CTL-fed cows was lower (P < 0.01) compared to those fed MON or PAP. The molar concentration of acetate and lactate was not affected (P > 0.23) by treatments, but feeding MON increased (P = 0.01) propionate during the first 4 days after the challenge. Feeding MON and PAP reduced (P = 0.01) the molar proportion of butyrate. MON was effective in controlling pH and improved ruminal fermentation of acidosis-induced cows. However, PAP was not effective in controlling acidosis. The acidosis induced by the challenge was caused by the accumulation of SCFAs. Therefore, the real conditions for evaluation of this feed additive were not reached in this experiment, since this PAP was proposed to work against lactate-producing bacteria.

Effects of substitution of millet straw for corn silage and alfalfa hay on lactation performance, ruminal fermentation, and blood metabolites in late-lactation Holstein dairy cows

The study was conducted to evaluate the effect of replacing dietary corn silage (CS) and alfalfa hay (AH) with millet straw (MS) on the production performance and the ruminal fermentation patterns of Holstein cows in late lactation. For this purpose, forty-eight multiparous Holstein dairy cows blocked by milk yield (32 ± 3.2 kg/d) and days in milk (179 ± 19 d) were randomly allocated to one of four treatments. The diets were formulated with a forage-to-concentrate ratio of 48:52 [dry matter (DM) basis] and contained the same concentrate mixtures, with different forage sources (on a DM basis): (1) Control (60% CS, 40% AH, and 0% MS; on 100% roughage); (2) LMS (54% CS, 36% AH, and 10% MS), (3) MMS (48% CS, 32% AH, and 20% MS), and (4) HMS (42% CS, 28% AH, and 30% MS). The dry matter intake and milk yield were lower in the HMS diet than those in the Control, LMS, and MMS diets (P < 0.01), whereas there was no difference in the Control, LMS, and MMS diets. Compared with the Control diet, 4% FCM, milk protein yield, and N conversion ratio decreased in the MMS and HMS diets (P < 0.01), whereas no difference between the Control and LMS diets was found. Besides, cows fed the HMS diet had lower milk fat yield, lactose percentage, and feed efficiency than those in the Control and LMS diets (P < 0.05), with no difference between the Control, LMS, and MMS diets. The percentage of milk fat and protein was not affected by the diets. Compared with the Control diet, the total VFA concentration was decreased, whereas the ammonia-N concentration was increased in the HMS diet (P < 0.05), with no difference between the Control, LMS, and MMS diets. The molar proportion of acetate and the ratio of acetate to propionate were lower (P < 0.01), while the molar proportion of propionate was higher in the Control diet than that in the MMS and HMS diets (P < 0.01), with no difference between the LMS and MMS diets. Compared with the Control, the apparent digestibility of DM, CP, NDF, and ADF was decreased, while the blood urea nitrogen concentration was increased in the HMS diet (P < 0.05), with no differences in the Control, LMS, and MMS diets. Thus, it was concluded that it is feasible to use MS as a fiber source for late-lactation dairy cows. However, considering the milk production performance and the feed digestibility, the replacement of CS and AH with MS should not exceed 20% of the roughage.

In vitro rumen fermentation pattern: insights from concentrate level and plant oil supplement.

The addition of oil to ruminant diets and oil fatty acid profiles are major factors that negatively affect ruminal fermentation, while increased forage level attenuates the adverse effects. The aim of this study was to determine the effects of oil source supplementation and concentrate level in the diet on in vitro ruminal fermentation kinetics. Pomegranate, garlic or sunflower oils were added (2 % dry matter (DM) basis) to the diets containing 40 % or 60 % (DM basis) concentrates. In vitro gas production parameters, pH, ammonia nitrogen concentration and total protozoa count were measured. Additionally, metabolizable energy (ME), short-chain fatty acid (SCFA) production and organic matter digestibility (OMD) were determined. Rumen fermentation parameters and protozoal population counts were analyzed as a completely randomized design with a 2 3 factorial arrangement of treatments, and gas production parameters were analyzed as a 2 3 factorial arrangement in a randomized block design. The results showed that the HCPO (high (60 %) concentrate diet containing pomegranate oil) and HCSO (high (60 %) concentrate diet containing sunflower oil) diets produced the highest (5.40 mg dL ) and lowest (2.61 mg dL ) concentrations of NH -N ( ), respectively. Total protozoa count tended ( ) to be highest in HCPO and lowest in HCSO diets (5.10 vs. 4.81Log10 g digesta). No interaction effects between the concentrate level and oil source were found on in vitro gas production parameters, pH, estimated ME, SCFA and OMD, and Entodinium and Diplodinium populations ( ). It is concluded that dietary supplementation with highly unsaturated oil from three different sources at 2 % level (DM basis) had no apparent effects on in vitro ruminal fermentation patterns.

Effect of brown and green seaweeds on diet digestibility, ruminal fermentation patterns and enteric methane emissions using the rumen simulation technique

Inclusion of the red seaweed Asparagopsis taxiformis as a feed additive, has led to significant reductions in methane (CH4) production from ruminants. However, dietary supplementation with this seaweed is negatively associated with health and environmental concerns mainly due to its bromoform content, a compound with potential carcinogenic properties. Thus, there is renewed focus on ascertaining the anti-methanogenic potential of locally grown brown and green seaweeds, which typically do not contain bromoform. The objective of this study was to investigate the effects of selected brown and green seaweeds on diet digestibility, ruminal fermentation patterns, total gas (TGP) and CH4 production in vitro, using the rumen simulation technique system. In experiment 1, Pelvetia canaliculata (PEC) was examined. In experiment 2, Cystoseira tamariscifolia (CYT), Bifurcaria bifurcata (BIB), Fucus vesiculosus (FUV), Himanthalia elongata (HIM) and Ulva intestinalis (ULI) were analysed. Ascophyllum nodosum (ASC) was included in both experiments. A diet containing A. taxiformis (ASP1; ASP2) and an unsupplemented diet (CON) were included as positive and negative controls, respectively in both experiments. All seaweeds were included at a rate of 10 g/kg dry matter (DM) into a control diet of 50:50 (w:w) forage:concentrate. The seven brown and green seaweeds assessed failed to affect absolute CH4 emissions or alter fermentation patterns. In experiment 1, seaweed treatment had no effect on diet digestibility, CH4%, CH4 mmol/d or CH4 L/d (P&amp;gt;0.1), however ASP1 reduced CH4 mmol/g DOM by 49% (P&amp;lt;0.01) relative to the control. Both ASC and ASP1 tended to increase TGP (P&amp;lt;0.1) relative to the control. In addition to this, the inclusion of seaweed in experiment 1 reduced the production of NH3-N (P&amp;lt;.0001) compared to the control. In experiment 2, seaweed treatment had no effect on diet digestibility or TGP. Both ASP2 and FUV reduced CH4% (P&amp;lt;0.01) but only ASP2 significantly reduced CH4 mmol/d, CH4 L/d and CH4 mmol/g DOM (P&amp;lt;0.05). Daily mMol butyrate was reduced by ASP2 relative to the control and most other seaweeds (P&amp;lt;.0001). In both experiment 1 and 2, seaweed inclusion had no effect on daily total VFA, acetate or propionate production or the acetate:propionate ratio relative to the control. To conclude, including the bromoform-free brown and green seaweeds at 10g/kg DM has no negative effects on diet digestibility or fermentation patterns but also failed to reduce the production of enteric CH4in vitro.

Influences of naringin supplementation on ruminal fermentation, inflammatory response, antioxidant capacity and bacterial community in high-concentrate diet of fattening goats

The objective of this study was to evaluate the effects of dietary naringin supplementation on rumen fermentation, inflammatory response and bacterial communities in fattening goats fed high-concentrate diet. Twenty four Boer male goats were randomly divided into three groups and assigned to receive dietary treatments. The three dietary treatments were a normal diet, a high-concentrate diet and a high-concentrate diet supplemented with 500 mg of naringin/kg of dry matter intake. Rumen fluid and plasma samples were collected at the end of the animal trial. Rumen fluid were analysed for pH, short-chain fatty acids, endotoxin (lipopolysaccharide, LPS) and microbiota. Illumina Miseq sequencing of the 16S rRNA gene was applied to investigate ruminal bacterial communities. The concentrations of interleukin −6 and tumour necrosis factor alpha as well as LPS-binding protein, haptoglobin, serum amyloid A and the activities of antioxdant enzymes in plasma were analysed. The result showed that feeding the high concentrate diet shifted the ruminal fermentation pattern from acetate towards propionate and valerate, and improved growth performance compared with the control group. However, the high concentrate diet promoted ruminal pH reduction and LPS release, modified bacterial communities and increased systemic inflammatory response. Naringin supplementation increased molar proportions butyrate and decreased valerate. Naringin supplementation decreased inflammatory response and increased the activities of antioxdant enzymes in plasma. Moreover, naringin addition increased the relative abundance of Bacteroidetes at the phylum level and Rikenellaceae_RC9_gut_group at the genus level. Taken together, these results suggest that dietary supplementation with naringin attenuates high grain diet-induced inflammatory response and modifies ruminal fermentation. HIGHLIGHTS Dietary supplementation of naringin decreased inflammatory response and increased the activities of antioxdant enzymes in fattening goats. Naringin supplementation changed ruminal microbiota of fattening goats. Naringin has potential for use as feed additive to modify ruminal fermentation in a high-grain intensive ruminant production.

The gas production, ruminal fermentation parameters, and microbiota in response to Clostridium butyricum supplementation on in vitro varying with media pH levels.

The aim of this study was to investigate the gas production (GP), dry matter disappearance (DMD), fermentation parameters, and rumen microbiota in response to Clostridium butyricum (CB) supplementation in batch culture using a high forage substrate. The doses of CB were supplemented at 0 (Control), 0.5 × 106, 1 × 106, and 2 × 106 CFU/bottle, respectively, at either media pH 6.0 or pH 6.6. The 16S rRNA gene sequencing was used to detect the microbiota of fermentation culture in control and 1 × 106 CFU/bottle after 24 h of incubation. The results showed that the GP (p < 0.001), DMD (p = 0.008), total volatile fatty acid (VFA) concentration (p < 0.001), acetate to propionate ratio (p < 0.001), and NH3-N concentration (p < 0.001) were greater at media pH 6.6 than pH 6.0. Furthermore, the linearly increased DMD (pH 6.0, p = 0.002; pH 6.6, p < 0.001) and quadratically increased butyrate proportion (pH 6.0, p = 0.076; pH 6.6, p < 0.053) and NH3-N concentration (pH 6.0, p = 0.003; pH 6.6, p = 0.014) were observed with increasing doses of CB. The Alpha diversity indexes of OTU number and Chao1 were higher (p = 0.045) at media pH 6.6 than pH 6.0, but they were not affected by CB supplementation. The PCoA analysis (unweighted uniFrac) demonstrated that the clustering of the bacterial microbiota of control and CB were distinctly separated from each other at media pH 6.0. At the phylum level, the abundance of Bacteroidota (p < 0.001) decreased, whereas that of Firmicutes (p = 0.026) increased when the media pH was elevated from 6.0 to 6.6. Supplementation of CB increased relative abundances of Rikenellaceae_RC9_gut_group (p = 0.002), Christensenellaceae_R-7_group (p < 0.001), and NK4A214_group (p = 0.002) at genus level. Interactions between media pH and CB addition were observed for bacteria at both phylum and genus levels. These results indicated that increasing the media pH level and CB supplementation increased in vitro rumen digestibility, and altered the ruminal fermentation pattern (by media pH) and microbiota.

Hematological, biochemical alterations and methane production in sheep submitted to mixed infection of Haemonchus contortus and Trichostrongylus colubriformis

The main current concern in ruminant production is focused on sustainability. In this sense, the objective was to evaluate ruminal fermentative alterations and methane (CH4) production, as well as hematological and biochemical alterations in sheep submitted to a single mixed infection with 10,000 infective larvae (L3) of Haemonchus contortus and 30,000 L3 of Trichostrongylus colubriformis. Twenty castrated males Santa Inês sheep, seven months old averaging 30.8 ± 6.41 kg of body weight were used. Ten animals were infected, and ten animals were uninfected, in a completely randomized design. During the experimental period, blood and ruminal content samples were collected, as well as the leftovers and diet provided. Enteric methane (CH4) production of the animals was measured at the end of the experiment. Parasitic infection affected dry matter intake, decreased red blood cell count, hemoglobin, and packed cell volume (PCV), and increased eosinophils and platelets numbers (P < 0.05). Ruminal fermentative changes were also observed, with changes in the short-chain fatty acid (SCFA) production profile, increase in propionate and decrease in acetate, and higher CH4 production in infected animals. Thus, it is concluded that H. contortus and T. colubriformis mix infection in sheep reduces forage dry matter consumption, causes hematological changes and ruminal fermentation patterns, impairing nutritional metabolism with greater CH4 production by infected animals.

How can nutritional additives modify ruminant nutrition?

This review illustrates the relationships between additives in the diets of ruminants and the consequence for ruminant nutrition. Feed additives are used to improve animal performance and/or the quality of the products. There are several categories of additives available for ruminant nutrition, with emphasis on antibiotics, prebiotics, probiotics, plant extracts, and exogenous enzymes. Antibiotics, essential oils, and chitosan act by selecting sensitive bacteria, consequently modulating the ruminal fermentation pattern. Prebiotics favor microbial growth, providing greater digestion and the production of volatile fatty acids. Probiotics are living microorganisms that improve the ruminal environment, promoting microbial growth and resulting in increased digestion and the production of volatile fatty acids. Exogenous enzymes act synergistically with the enzymes secreted by the ruminal microorganisms, besides favoring microbial adhesion and colonization and facilitating feed degradation. Tannins, whether altering the fermentation standard and/or modifying the ruminal microbiota population, are effective in improving animal performance. However, the effects of additives on the quality of the products are linked to diet quality. Highlights Exogenous enzymes act synergistically with the enzymes secreted by the ruminal microorganisms. Exogenous enzymes favoring the microbial adhesion and colonization of the particles, aid in the degradation of the feed. Tannins can altering the fermentation standard and/or modifying the ruminal microbiota population. Essential oils and chitosan act by selecting sensitive bacteria and consequently modulate the ruminal fermentation.

Impacts of added roughage on growth performance, digestibility, ruminal fermentation, and ruminal pH of feedlot steers fed wheat-based feedlot diets containing 30% modified distillers grains with solubles.

Two experiments were conducted to evaluate the inclusion rate roughage in wheat-based diets containing modified distillers grains with solubles (MDGS) on feedlot performance (Feedlot Experiment), as well as digestibility, ruminal pH, and ruminal fermentation characteristics (Digestibility Experiment). The feedlot experiment utilized 72 Angus steers (392 ± 46.3 kg initial body weight) which were randomly assigned to 1 of 12 pens, 3 pens per treatment, to evaluate feedlot performance and carcass characteristics. Dietary treatments were 1) control; 10% roughage, 2) 12% roughage, 3) 14% roughage, and 4) 16% roughage. The digestibility experiment used four ruminally and duodenally cannulated steers (393 ± 33.0 kg) in a 4 × 4 Latin Square with either 10%, 12%, 14%, or 16% roughage as in the feedlot experiment. However, dietary roughage source was different between these two experiments and included a combination of grass hay and wheat straw (Feedlot Experiment), and corn silage (Digestibility Experiment). All data were analyzed with the Mixed Procedures of SAS. Feed intake was recorded, with duodenal and fecal output calculated using chromic oxide. Ruminal pH and fermentation were assessed. Growth performance and most carcass characteristics were not affected by increasing roughage (P ≥ 0.11). Marbling tended to decrease linearly (P = 0.10) with increasing roughage inclusion. Increasing dietary roughage content had no effect on organic matter intake (P = 0.60) in the digestibility experiment. Intake, duodenal flow, and digestibility of neutral detergent fiber and acid detergent fiber were not affected by treatment (P ≥ 0.16). Ruminal pH increased linearly (P < 0.01) as rate of roughage inclusion increased. Ruminal concentrations of acetate and butyrate increased, and propionate decreased in a linear fashion (P < 0.01) thereby increasing (P < 0.01) acetate and butyrate to propionate ratio with increasing dietary roughage. Our data indicate that increasing roughage inclusion in wheat-based diets including 30% MDGS increased ruminal pH and shifted ruminal fermentation patterns. Additionally, increasing roughage inclusion did not affect feedlot performance in steers fed wheat at 36% to 42% of dietary dry matter in combination with 30% MDGS.

Effect of dietary isopropanol on the performance and milk quality of dairy cows

The objective of this study was to examine the effects of isopropanol alone or in combination with ethanol on performance, metabolism, and milk quality of dairy cows. Eight crossbred Jersey × Holstein cows (527 ± 98 kg body weight; 152 ± 44 days in milk) were allocated in two 4 × 4 balanced-Latin squares to receive one of four dietary treatments. Four cows were surgically adapted with rumen cannula. Diets contained 450 g/kg concentrates and 550 g/kg corn silage either added with (DM basis) 15 g/kg isopropanol, 15 g/kg ethanol, 15 g/kg isopropanol + 15 g/kg ethanol, or water (control). Immediately before feeding, corn silage was sprayed with alcohols, mixed with concentrates, and fed as total mixed rations twice daily. Dry matter intake, total tract digestibility, ruminal fermentation pattern (pH, volatile fatty acids and NH3), urinary purine derivatives, milk yield, solids composition and oxidative capacity were not affected by treatments. However, gamma-glutamyl transferase activity increased (P < 0.01) in blood of cows supplemented with alcohols, indicating that isopropanol and ethanol were absorbed. Moreover, milk concentration of isopropanol and acetone increased (P < 0.01) in cows receiving isopropanol, but not ethanol. Consequently, milk from cows fed corn silage treated with isopropanol tested false-positive at the ethyl alcohol test in raw milk. In conclusion, dietary isopropanol and ethanol did not impair the performance of dairy cows, but isopropanol was imparted to milk and induced false-positive results at the ethyl alcohol test in raw milk.

Leucaena leucocephala leaves and prickly pear (Opuntia ficus-indica) as substitutes for alfalfa hay (Medicago sativa L.) and their effects on the gas and methane production, prevalence of methanogens and patterns of ruminal fermentation in vitro

The aim of the study was to evaluate the replacement of alfalfa hay with Leucaena leucocephala leaves and prickly pear (Opuntia ficus-indica) as an alternative forage, on gas and methane production, ruminal fermentation patterns and total amount of methanogens during in vitro fermentation. Four treatments were evaluated: (T1) alfalfa hay + concentrate (50 : 50%, DM); (T2) alfalfa hay + Leucaena leaves + concentrate (30 : 20 : 50%, DM); (T3) alfalfa hay + prickly pear + concentrate (30 : 20 : 50%, DM) and (T4) alfalfa hay + Leucaena leaves + prickly pear + concentrate (30 : 10 : 10 : 50%, DM). The higher gas production from of soluble fraction (A) and rate gas production (Kd) values, ammonia-N (NH3-N) concentrations and propionate were found in T1 and lower in T2 (p&lt;0.05). Nevertheless, the inclusion of Leucaena leucocephala in the diet decreased the methane production and did not affect the total of methanogens. Results showed that the replacement of alfalfa hay by Leucaena leucocephala and Opuntia ficus-indica in a diet do not affect the main variables of in vitro gas production, ruminal fermentation patterns and methanogenic microorganisms populations.

Can a blend of integrated feed additives modulate ruminal fermentation patterns and performance of growing lambs? In vitro and in vivo assessments

Two in vitro and in vivo experiments were accomplished to investigate the impacts of integrated feed additives (IFA, combination of protected fat, lysine, and methionine plus yucca extract, eucalyptus essential oil, and direct-fed microbial) on gas production (GP), ruminal fermentation and degradability parameters and lamb performance, digestibility, and nitrogen balance. In the in vitro experiment, responses of graded doses (0, 25, 50, 75, 100, and 125 g IFA/kg DM) were evaluated. In the in vivo experiment, 15 Barki male lambs (30.43 ± 0.74 kg BW ± SE) were individually allotted in complete randomized design into three treatments (five animal/treatment) as control (basal diet without additive), low dose (50 g/kg DM) and high dose (100 g/kg DM) for 120 days. In vitro results showed that both doses (100 and 125 g/kg DM) quadratically decreased (p < 0.001) GP and ammonia nitrogen (NH-3N) concentration. In vivo experiment revealed that dry matter intake was increased (p = 0.016) with low dose compared to high dose. Inclusion of high dose decreased blood serum glucose concentrations (p > 0.05) and ruminal protozoal populations (p = 0.094) compared with low dose and control diet. Both doses of IFA increased (p < 0.05) serum urea, creatinine, and triglyceride concentrations, while decreased (p < 0.001) ruminal NH3-N concentrations. These results suggested that, although IFA was effective to modify in vitro ruminal fermentation process and feed degradability, such aspects did not improve in vivo performance of growing lambs.

Modified Nano-Montmorillonite and Monensin Modulate In Vitro Ruminal Fermentation, Nutrient Degradability, and Methanogenesis Differently.

Simple SummaryNatural montmorillonite (NM) is the most common clay used as a feed additive in ruminant diets. Under normal pH conditions, it can adsorb hydrogen and may affect methane (CH4) formation; however, it possesses less efficiency than other clays. Due to NM’s negative charge flat surface and positive charge edges, its physicochemical properties can be modified by cationic or anionic surfactants. Therefore, two types of modified nano-montmorillonite (MNM) were developed by ion-exchange reactions using cationic and anionic surfactants. Comparisons were made with monensin as a rumen modulator to reduce CH4 emission from ruminants. The results indicated that the physicochemical properties of both MNM types were enhanced (e.g., cation-exchange capacity and zeta potential). All MNM clays and monensin successfully reduced rumen CH4 production and ammonia concentration; however, clay modified by cationic surfactant was more efficient than what was modified by anionic surfactant in modulating in vitro rumen fermentation propertiesTwo types of modified nano-montmorillonite (MNM) were developed by ion-exchange reactions using two different surfactants; sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CETAB), to prepare MNMSDS and MNMCETAB, respectively. Both MNM types were on the nano-scale and had higher cation-exchange capacity values than NM clay. The MNMCETAB had the highest zeta potential (−27 mV) compared with the other clays. Effects of MNM types on in vitro ruminal batch culture fermentation, nutrient degradability, and methane (CH4) emission compared with monensin were evaluated in vitro using a semi-automatic gas production system. The experimental treatments were the control (0 supplementations), monensin (40 mg/kg DM), and NM (5 g NM/kg DM), and two levels of MNMSDS and MNMCETAB were supplemented at 0.05 (low) and 0.5 (high) g/kg DM to the control basal feed substrate. Among the experimental treatments, the high dose of both MNM types reduced (p < 0.01) CH4 production and ammonia concentrations compared with the control, while only MNMCETAB treatment tended to increase (p = 0.08) the truly degraded organic matter compared with monensin. All MNM treatments increased (p < 0.01) acetate molar proportions compared with monensin. The high MNMCETAB increased (p < 0.01) the in vitro ruminal batch culture pH compared with the control and monensin. The MNMCETAB supplemented at 0.5 g/kg DM is the most efficient additive to reduce CH4 emission with the advantage of enhancing the in vitro nutrient degradability of the experimental feed substrate. These results indicated that MNM could modulate the in vitro ruminal fermentation pattern in a dose- and type-dependent manner.

Effect of Alfalfa Hay Substitution by Raw Garlic Leaves on In vitro Gas Methane Production and Ruminal Fermentation

Background: The aim of present research was to evaluate under in vitro conditions, the effect of alfalfa hay substitution by raw garlic leaves on ruminal fermentation patterns and methane production in diets ruminants. Methods: Four treatments were evaluated: (T1) alfalfa hay (50%); (T2) alfalfa hay (33%) + raw garlic leaves (17%); (T3) alfalfa hay (17%) + raw garlic leaves (33%) and (T4) raw garlic leaves (50%). Result: The highest values of fractional rate of gas production (kd), ammonia-nitrogen (NH3-N), propionate and microbial biomass synthesis (MBS) was recorded in T4 and the lowest in T1 (P less than 0.05). In contrast, the highest methane production was recorded in T1 and the lowest in T4 (P less than 0.05). It was concluded that the substitution of alfalfa hay by raw garlic leaves in diet with 50% roughages and 50% concentrate result in an improvement in vitro rumen fermentation pattern and decreases the methane production.