Feeding of by-products completely replaced cereals and pulses in dairy cows and enhanced edible feed conversion ratio

Abstract

When fed human-edible feeds, such as grains and pulses, dairy cows are very inefficient in transforming them into animal products. Therefore, strategies to reduce human-edible inputs in dairy cow feeding are needed to improve food efficiency. The aim of this feeding trial was to analyze the effect of the full substitution of a common concentrate mixture with a by-product concentrate mixture on milk production, feed intake, blood values, and the edible feed conversion ratio (eFCR), defined as human-edible output per human edible input. The experiment was conducted as a change-over design, with each experimental period lasting for 7wk. Thirteen multiparous and 5 primiparous Holstein cows were randomly assigned to 1 of 2 treatments. Treatments consisted of a grass silage-based forage diet supplemented with either conventional ingredients or solely by-products from the food processing industry (BP). The BP mixture had higher contents of fiber and ether extract, whereas starch content was reduced compared with the conventional mixture. Milk yield and milk solids were not affected by treatment. The eFCR in the BP group were about 4 and 2.7 times higher for energy and protein, respectively. Blood values did not indicate negative effects on cows' metabolic health status. Results of this feeding trial suggest that by-products could replace common concentrate supplements in dairy cow feeding, resulting in an increased eFCR for energy and protein which emphasizes the unique role of dairy cows as net food producers.

The net contribution of dairy production to human food supply: The case of Austrian dairy farms

“…Comparing two different Californian dairy rations, Oltjen and Beckett (1996) estimated heFCE of 0.57 and 0.96 for energy and protein, respectively, for a ration containing large proportions of maize and soy and 1.28 and 2.76 for a least cost ration in which industrial by-products were used as concentrate supplements. In a shortterm feeding trial with mid lactating dairy cows, the substitution of commonly used concentrates with by-products from the food processing industry increased the heFCE from 1.39 to 5.55 and from 1.60 to 4.27 on an energy and protein basis, respectively (Ertl et al, 2015).…”

“…As a result, in some cases beef and dairy production systems even show a heFCE below 1, indicating a net food drain (CAST -Council for Agricultural Science and Technology, 1999;Oltjen and Beckett, 1996;Wilkinson, 2011). Although heFCE has already been calculated for dairy cows based on data from model calculations (Oltjen and Beckett, 1996;Wilkinson, 2011), whole country data (CAST -Council for Agricultural Science and Technology, 1999), or short term feeding trials (Ertl et al, 2015), an analysis of field data from a range of practical dairy farms regarding their heFCE is still lacking. The aim of the present study was therefore to calculate the heFCE for Austrian dairy farms in order to evaluate the potential range of the contribution of dairy production to the net food supply.…”

“…The aim of the present study was therefore to calculate the heFCE for Austrian dairy farms in order to evaluate the potential range of the contribution of dairy production to the net food supply. A major problem when calculating the heFCE for a single animal or a whole production system is evaluating the potential human-edible input via feedstuffs (Ertl et al, 2015;Le Cotty and Dorin, 2012;Wilkinson, 2011). Therefore, the second aim of this study was to provide literature-based estimates for the human-edible fractions (heF) of feedstuffs used on the selected farms.…”

Upgrading plant amino acids through cattle to improve the nutritional value for humans: effects of different production systems

“…Thus values <1 indicate higher output of protein in products than input of protein in feeds. Ertl et al (2015a) suggested that the efficiency should be calculated as output/input and results from their study showed higher efficiency on a forage/by-product-based dairy cow diet (4.27) compared with the F11000 system used in the present study (1.71). However, Ertl et al (2015a) did not include input of feed to replacement heifers, feed during the dry period or output of meat from culled cows, but concluded that the most important factor for the results obtained was determination of the human-edible fraction in the feeds.…”

“…Ertl et al (2015a) suggested that the efficiency should be calculated as output/input and results from their study showed higher efficiency on a forage/by-product-based dairy cow diet (4.27) compared with the F11000 system used in the present study (1.71). However, Ertl et al (2015a) did not include input of feed to replacement heifers, feed during the dry period or output of meat from culled cows, but concluded that the most important factor for the results obtained was determination of the human-edible fraction in the feeds. This point was clearly shown in the present study, where F11000 was Figure 1 Calculated balance of net quantities of digestible essential amino acids in human-edible feeds and in milk and meat per year in different dairy production systems: reference, R9000; intensive maize, M11000; intensive by-products from food, F11000; extensive, E7000.…”