ISSUE FOCUS FEED & ADDITIVE MAGAZINE September 2023 21 Both protein and energy valorization are important and furthermore, correlated. Indeed, microbial synthesis of protein is energy dependent, and research has shown that “synchronizing” the timing of energy supply with protein degradation may maximize protein synthesis and minimize nitrogen waste into ammonia. HOW PHYTOGENICS CAN IMPROVE ENERGY AND PROTEIN USE IN THE RUMEN? Phytogenics are added to the overall diet and can affect protein and energy from all the different feed components (forages, cereals, meals, etc.). There are numerous types of phytogenics and some of the most effective ones for feed efficiency are: • Tannins: Complex polyphenol compounds of plants. They can vary a lot in types and concentration from extraction. Their nature allows binding with protein, notably, but the quantity and the quality of the extract is very important to ensure adequate binding in the rumen and liberation in the gut. • Essential oils: There are various families with different mode of actions. In the literature, these compounds have shown antimicrobial activities used to modify ruminal fermentations of protein and energy, to secure digestion and improve, and to improve nutrient digestibility and increase productivity. • Spices: Spices have shown to increase dairy cows’ intake in different trials, and have been linked to increase of natural buffer from salivation positively affecting ruminal pH. MiXscience has developed a specific range of products including different combination of these components. These products have been developed and tested in the Mixscience Research Center (MRC, Saint-Symphorien, France) in order to increase protein and energy efficiency of ruminants. In studies, high doses of essential oils have been associated with detrimental effect on rumen microorganisms but doses and effects were varying. One of these products, Valopro NRJ, has been recently tested at MRC with higher dosage to assess cows’ response: • 30 lactating Holstein dairy cows (60% primiparous cows; 184 ± 64 days in milk (DIM); 35.6 ± 6.8 kg of milk/day; 723 ± 67 kg body weight) • Herd diet: 16.2% protein, 34.8% NDF, 1.65 MCal/kg • Cows blocked by lactation number, DIM, milk yield, protein and fat contents • Two groups: Herd diet (42 days) with 0 g/cow/d (control group) or 30 g/cow/d of Valopro NRJ group. • Individual milk yield and composition (protein, fat, urea, SCC) monitored daily and weekly respectively • Individual intake and body weight assessed every day Per cow per day Partial Mixed Ration AMS* Feeder Production concentrate from 0 to 5 kg linked to Milk Yield (average 3 kg) Trial feed 3.0 kg Control feed 3.0 kg AMS* = Automatic Milking System AMS Feeder Corn silage 10kg DM Grass silage 3.3kg DM Liquid feed 1.0 kg Basemix 0.23 kg Rumen protected Fat 0.1 kg Protein concentrate 1.7 kg Energy concentrate 2.0 kg Control Valopro NRJ
RkJQdWJsaXNoZXIy MTUxNjkxNQ==