water soluble and contains a mixture of three lactic acid-producing organisms to be used in a wide variety of forages chopped for ensiling.


You can preserve your forage investment through the use of silage additives. Silage additives improve fermentation, reduce heating, reduce mold and storage losses, and improve the nutritive value and digestibility of ensiled forage.

Features and Benefits

Kem LAC® HD is water soluble and contains a mixture of three lactic acid-producing organisms to be used in a wide variety of forages chopped for ensiling. This high density formula provides more bacteria per gram than other products available in the market. Kem LAC HD contains a mixture of lactic acid-producing bacteria (LAB) to help speed fermentation.1 These bacterial strains are: Lactobacillus plantarum, Lactobacillus acidophilus and Lactobacillus bulgaricus. The high levels of lactic acid produced by this combination of bacteria helps to quickly lower pH and preserve the crop.

Kem LAC HD works in a wide variety of forages including corn, wheat, sorghum and alfalfa silage to help reduce dry matter loss and preserve nutrient availability. By retaining dry matter, Kem LAC HD helps to optimize the nutritional quality of your crop by retaining more energy and protein. Kem LAC HD also controls silage temperatures in the silo while helping to reduce silage loss or shrinkage.

How Does Kem LAC HD Silage Inoculant Work?

The increased rate in pH reduction is due to inoculation with beneficial lactic acid-producing bacteria (LAB), which produce large volumes of acid. Lactic acid is one of the strongest organic acids found in silage. One important key to silage production is to decrease the pH as rapidly as possible to below a pH of 5.0, which stabilizes silage by inhibiting growth of unfavorable molds and bacteria.2


Lactic acid is the organic acid found in the highest concentration in well-conserved silage.3 Lactic acid-producing bacteria are those most commonly found in bacterial inoculants because of the ability of lactic acid to quickly drop the pH of silage. Lactobacillus plantarum is the most prevalent species used in commercial inoculants with various strains selected for their ability to produce large quantities of lactic acid. Homofermentative, anaerobic bacteria are used in commercial silage inoculants because they convert more of the plant mass into lactic acid (two molecules of lactic acid for each molecule of glucose fermented). Heterofermentative, anaerobic bacteria are also used in silage inoculants to produce lactic acid and acetic acid, but their fermentation results in the production of carbon dioxide, a gas which results in dry matter loss.

A trial evaluated the effectiveness of two water soluble bacterial silage inoculants, Kem LAC® HD (KL) and an industry leading silage inoculant (Product B5), for changing pH and promoting organic acid production in corn silage. Corn silage was treated with KL, B5 or water as a negative control (NC). The objective of this inoculant evaluation was to measure the effects of KL, which contains three LAB organisms, versus B5, which contains two strains of Lactobacillus plantarum. The only acid production in the negative control came from epiphytic (natural) bacteria found in untreated corn silage.

Both of the silage inoculants, Kem LAC HD and B5, promoted faster pH drop and more complete fermentation than the untreated silage. Both treatments produced greater (P < 0.05) amounts of lactic acid and significantly lower (P < 0.05) pH by 28 days post ensiling. Kem LAC HD-treated silage produced less (P < 0.05) ammonia than both the B5 and NC-treated silages by 28 days post ensiling. This suggests the Kem LAC HD-treated silage conserved more protein during the fermentation process. The pH of Kem LAC HD and B5-treated silages remained lower during the entire 120 day fermentation (Figure 1) and were significantly lower (P ≤ 0.05) after 120 days of fermentation than the NC-treated silage.

Kem LAC HD Trial Graph 1

Figure 1. Patterns for pH change in corn silage through 120 days in packet and bucket silos.

Varying degrees of aerobic deterioration occur before and during feeding on most farms. The inability to remove sufficient quantities of silage from silos between feedings or poorly packed silage are two difficulties producers must overcome. Feeds that undergo aerobic deterioration have reduced nutritional value and present challenges and waste such as disposal of spoiled feed. Milk yield of cows fed aerobically unstable corn declined approximately 7 lbs during 14 day feeding periods.4 Improving the aerobic stability of silages could confer a substantial advantage to producers.

Another trial evaluated the effectiveness of Kem LAC HD (KL) and Product BA on the aerobic stability of alfalfa silage. Second-cutting alfalfa was treated with Kem LAC HD, BA or water, as a negative control (C). The objectives of this inoculant evaluation were to assess the effects of Kem LAC HD versus BA versus epiphytic bacteria on fermentation, dry matter (DM) recovery, aerobic stability and feeding value of alfalfa silage.

Kem LAC HD Trial Graph 2

Figure 2. Temperature of plant material over time during aerobic exposure of alfalfa ensiled for 75 days.

The data collected during this trial show Kem LAC HD and BA prevented alfalfa silage from heating for a significantly longer (P = 0.043) period of time compared to control silage. Both inoculants would impart greater stability to the silage in order to help producers manage feeding strategies. For livestock producers, stability in both feed out and TMR mixes in the bunk promotes improved intakes and performance.



  1. Kemin Internal Document, 16-00024.
  2. Kemin Internal Document, 11-00000.
  3. Kemin Internal Document, 12-00015.
  4. Kemin Internal Document, 12-00008.

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