Review: Alternative and novel feeds for ruminants: nutritive value, product quality and environmental aspects

Abstract

Ruminant-based food production faces currently multiple challenges such as environmental emissions, climate change and accelerating food–feed–fuel competition for arable land. Therefore, more sustainable feed production is needed together with the exploitation of novel resources. In addition to numerous food industry (milling, sugar, starch, alcohol or plant oil) side streams already in use, new ones such as vegetable and fruit residues are explored, but their conservation is challenging and production often seasonal. In the temperate zones, lipid-rich camelina (Camelina sativa) expeller as an example of oilseed by-products has potential to enrich ruminant milk and meat fat with bioactive trans-11 18:1 and cis-9,trans-11 18:2 fatty acids and mitigate methane emissions. Regardless of the lower methionine content of alternative grain legume protein relative to soya bean meal (Glycine max), the lactation performance or the growth of ruminants fed faba beans (Vicia faba), peas (Pisum sativum) and lupins (Lupinus sp.) are comparable. Wood is the most abundant carbohydrate worldwide, but agroforestry approaches in ruminant nutrition are not common in the temperate areas. Untreated wood is poorly utilised by ruminants because of linkages between cellulose and lignin, but the utilisability can be improved by various processing methods. In the tropics, the leaves of fodder trees and shrubs (e.g. cassava (Manihot esculenta), Leucaena sp., Flemingia sp.) are good protein supplements for ruminants. A food–feed production system integrates the leaves and the by-products of on-farm food production to grass production in ruminant feeding. It can improve animal performance sustainably at smallholder farms. For larger-scale animal production, detoxified jatropha (Jatropha sp.) meal is a noteworthy alternative protein source. Globally, the advantages of single-cell protein (bacteria, yeast, fungi, microalgae) and aquatic biomass (seaweed, duckweed) over land crops are the independence of production from arable land and weather. The chemical composition of these feeds varies widely depending on the species and growth conditions. Microalgae have shown good potential both as lipid (e.g. Schizochytrium sp.) and protein supplements (e.g. Spirulina platensis) for ruminants. To conclude, various novel or underexploited feeds have potential to replace or supplement the traditional crops in ruminant rations. In the short-term, N-fixing grain legumes, oilseeds such as camelina and increased use of food and/or fuel industry by-products have the greatest potential to replace or supplement the traditional crops especially in the temperate zones. In the long-term, microalgae and duckweed of high-yield potential as well as wood industry by-products may become economically competitive feed options worldwide.

The effect of partial substitution of rapeseed meal and faba beans by Spirulina platensis microalgae on milk production, nitrogen utilization, and amino acid metabolism of lactating dairy cows

“…Results of AA metabolism were affected by both AA profile and ruminal protein degradability of the experimental protein feeds. Histidine and methionine are important AA to consider for diets supplemented by FB and spirulina because spirulina is low in histidine but rich in methionine (Lamminen et al, 2017(Lamminen et al, , 2019, whereas the opposite is true for FB, similar to many grain legumes (Aguilera et al, 1992;Halmemies-Beauchet-Filleau et al, 2018). Methionine may limit milk production in cows on FB-supplemented diets (Puhakka et al, 2016), and histidine is typically the first limiting AA with diets based on cereal and grass silage (Kim et al, 1999;Vanhatalo et al, 1999).…”

“…However, the protein value of FB may be impaired by their considerably high rumen degradability and low concentration of methionine (Aguilera et al, 1992;Duc et al, 1999;Luke, 2019), which is often the limiting AA for milk production (e.g., Pisulewski et al, 1996). Indeed, compared with rapeseed, FB have resulted in lower milk and protein yields in dairy cows (Puhakka et al, 2016;Ramin et al, 2017;Halmemies-Beauchet-Filleau et al, 2018). Previously, balancing the AA supply in metabolizable protein has increased milk and protein yields and improved the conversion of feed N into milk protein (N use efficiency, NUE; Haque et al, 2012), consequently leading to decreased N emissions to the environment.…”

Camelina, an ancient oilseed crop actively contributing to the rural renaissance in Europe. A review

“…Camelina meal is more palatable than flax meal for laying hens, and the quality properties of the eggs and the eggshells are better (Cherian and Quezada 2016;Lolli et al 2020;Rokka et al 2002). Regarding milk production, the inclusion of camelina meal in the feeding of ewes (Ovis aries) and ruminants allows the production of lowsaturated milk with an increased content of PUFAs (Colombini et al 2014;Halmemies-Beauchet-Filleau et al 2017;Halmemies-Beauchet-Filleau et al 2018;Szumacher-Strabel et al 2011). Nonetheless, the presence of antinutritional factors such as glucosinolates, phytic acid, sinapine, and condensed tannins represents an obstacle to the increase in the inclusion rate in animal rations (Colombini et al 2014).…”

Quelle science pour les élevages de demain ? Une réflexion prospective conduite à l’INRA

“…a. Remobiliser dans la chaîne alimentaire des gisements de biomasse et de protéines non comestibles par l'Homme, grâce à l'élevage L'élevage peut permettre de valoriser des biomasses produites par la diversification des rotations rendue nécessaire pour limiter l'usage des pesticides et de nouveaux gisements de coproduits peuvent aussi être identifiés (Halmemies-Beauchet-Filleau et al, 2018). Ces nouvelles ressources alimentaires seront souvent très variables dans l'espace, le temps et en qualité ce qui pose des questions spécifiques.…”