• Charolais beef cattle

How fibre digestion drives beef cattle performance

Fibre digestion is a key-driver to optimise beef cattle performance. However, acute and subacute rumen acidosis (SARA) frequently affect intensively reared beef cattle. They are fed high-energy diets rich in highly fermentable carbohydrates. Hence, the rumen produces an excessive load of lactic acid leading to hyperacidity of the rumen.

Sgoifo Rossi & Compiani, (2016) state that rumen acidosis is considered the most important nutritional disorder of beef cattle all around the world with significant economic and welfare implications. In normal conditions, there is a balance between the rumen microbial populations, which leads to an efficient fermentation activity.

The main trigger leading to ruminal acidosis is the excessive consumption of fermentable carbohydrates and the abrupt transition from a diet consisting mainly of forages to one mainly composed of cereals. The accumulation of volatile fatty acids decreases rumen pH. Hence, the rumen loses its ability to buffer the rumen and this subsequently reduces the efficiency of ruminal microorganisms and fermentation.

In case of acute rumen acidosis, beef cattle present signs and symptoms of gastrointestinal disorders, reduced appetite and impaired general health condition. With sub-clinical acidosis (SARA), the overall health impairment is rare. In short term, cattle show only a reduction of feed intake, followed by secondary health problems in the medium and long term.

The impact of the various volatile fatty acids on rumen fermentation are also explained in the article “How to reduce the risk for rumen acidosis?”

Question is “How to enhance rumen health, drive fibre digestion and improve production performance for intensively reared beef cattle?”

Beef cattle signals of (sub-acute) rumen acidosis:

  • reduced feed intake
  • decline in growth performance
  • loose manure
  • rumen bloat: excessive volume of gass in the rumen
  • damage of the gastrointestinal tissue
  • inflammation due to the release of toxic substances from pathogenic bacteria
  • liver abscess
  • laminitis

A comparison of rumen buffers

Sodium bicarbonate is commonly used in  beef cattle diets to reduce the risk for rumen acidosis. Rossi and co-workers compared the efficacy of 80 g/head/day sodium bicarbonate vs. Acid Buf with half this amount (40 g/head/day) in the diet of beef cattle.

Growth performance was assessed at a typical north-Italian intensive fattening unit. The trial involved 180 Charolaise bullocks beef cattle at 14 months of age with an average starting weight of 536 kg.

The two dietary treatments were given for the entire fattening period of 130 days:

  • Control group fed with 80 gram/head/day sodium bicarbonate
  • Treatment group fed with 40 gram/head/day of Acid Buf

Both products were incorporated in the mineral and vitamin premix of the cattle diets. Acid Buf replaced limestone and sodium bicarbonate. Salt was added to maintain sodium levels at 0.4%. The cattle diets were offered ad libitum and the formulation was consistent throughout.

Specification of the cattle diets

Acid Buf in cattle feed diet

Increasing fibre digestion

The potential for increasing fibre digestion with sodium bicarbonate or Acid Buf was also researched. Rumen health was monitored with the use of a rumen bolus. The bolus administrated the pH development in three animals per treatment during the day. Rumen pH was recorded every 10 minutes.

The work of Rossi et al. (2019) clearly demonstrates that:

  • Acid Buf increased mean rumen pH compared to sodium bicarbonate (P<0.001)
  • Acid Buf reduced the time that rumen pH was below the safety threshold of 5.6. In the first 15 days after the diet change, the sodium bicarbonate group spend on average 4:09 hours per day below pH 5.6 vs. only 12 minutes per day for the Acid Buf treatment
  • Beef cattle on the sodium bicarbonate diet needed more time to adapt their rumen activity to the new cattle diet
  • Acid Buf reduced the risk of rumen acidosis, especially during the transition from the starter to the finishing diet after 8 days
  • Acid Buf reduced the prevalence of acidosis related diseases (P=0.05)
    • Bloat: sodium bicarbonate 1 vs. Acid Buf 0
    • Lameness: sodium bicarbonate 5 vs. Acid Buf 1

These results may demonstrate a better activity of ruminal bacteria and protozoa.

Video: results rumen pH and acidosis (Rossi et al. 2019)

Acid Buf increases fibre digestion

Acid Buf drives fibre digestion

Qualitative faeces evaluation (Rossi et al. 2019)

Acid Buf reduced the risk for rumen acidosis. The long-term buffering activity generated a healthy rumen function through enhancing the optimum rumen pH throughout the day. The improved rumen fermentation with Acid Buf, as compared to sodium bicarbonate, was also confirmed by the feacal analysis. Acid Buf improved fibre digestion at rumen level. Data showed:

  • higher proportion of fine particles in the undigested fraction (P<0.01)
  • lower faecal NDF (P<0.10) and higher ADF (P<0.01)

The solid residual in the first and in the second sieve was higher for sodium bicarbonate. However, the solid residual in the third sieve was higher for Acid Buf. Smaller particles in manure is evidence of a better dry matter digestion. Hence, Acid Buf gives a better and more effective fermentation of the digestible fibre in the diet.

Acid Buf drives beef cattle performance

Optimising rumen pH and increasing fibre digestion results in a clear response. Acid Buf in the beef cattle diets for 130 days increased production performance. The results show that:

  • Acid Buf significantly increased (P<0.001) weight gain with 81 g/head/day in respect to sodium bicarbonate
  • Acid Buf showed a trend towards statistical difference of 80 g/head/day in the adaptation phase (days 0-21, P=0.08)
  • The maximum growth difference between the dietary treatments was detected during the middle of the fattening period (days 21-100, P<0.05)
  • Beef cattle fed Acid Buf had a significantly improved FCR (P<0.05) of 7.66 kg dry matter intake per kg weight gain vs. 8.18 kg/kg for sodium bicarbonate. This reflects a 6% improvement with Acid Buf
  • Dry matter intake was equal between experimental groups

Also, beef cattle that received Acid Buf instead of sodium bicarbonate tended to exhibit a lower overall number of fighting or mounting events (P=0.09). This is in line with previous research done with pigs (O’Driscoll et al., 2012).

Growth performance parameters (Rossi et al. 2019)

Acid Buf increases daily weight gain and FCR for beef cattle

a,b Means within a row with different superscripts differ (P< 0.05)


The replacement of 80 g sodium bicarbonate with 40 g of Acid Buf as a rumen buffer resulted in significant better growth performance and feed conversion ratio in beef cattle during the finishing phase of 130 days. This improved performance is the result of e a greater rumen stability which led to a health improvement reducing the level of rumen acidosis and other related problems.

Acid Buf showed feed efficiency benefits, which may become far reaching in the future. Sustainable farming and environmental constraints force beef producers to optimise weight gains per kilo of dry matter consumed by beef cattle.

The paper of Rossi and co-workers is published in the Brazilian Journal of Animal Science. Download the full article here and get powered by our science.

Acid Buf offers nutritional solutions for:

  • long term pH optimisation in the rumen
  • increasing fibre and total dry matter digestion
  • healthy rumen functioning, reducing subclinical rumen acidosis (SARA)
  • increasing weight gains & feed conversion ratio
  • promoting a calmer behaviour
  • global agriculture sustainability goals

Related articles

Heat stress in dairy cows
Dairy systainability and feed efficiency
CeltiCal supports animal welfare
Charolais beef cattle on grass
Acid Buf drives dairy cow performanceCeltic Sea Minerals
Acid Buf reduces the risk for grass staggers
Gastric Ulcers Swine Nutrition
Marine Minerals for animal feed applicationCeltic Sea Minerals
Acid Buf increases milk butterfatCeltic Sea Minerals
How to reduce the risk for rumen acidosisCeltic Sea Minerals

You want to get powered by our science?