Functional diversity vs. monotony: the effect of a multiforage diet as opposed to a single forage diet on animal intake, performance, welfare, and urinary nitrogen excretion

Abstract

The objective of this study was to determine the effect of offering animals a multi-forage choice of fresh herbages on dry matter intake (DMI), live weight gain and animal welfare, in comparison with a monotonous diet of ryegrass (Lolium perenne L.). Twenty ram lambs [30.5 ± 0.9 kg initial live weight; mean ± standard error of the mean], were randomly allocated to either a diet consisting of diverse multi-forage choice (MF) or a single forage ryegrass (SF) diet (n = 10 per treatment) for 35 days. Both diets were fed ad libitum; however, the MF diet was composed of set dry matter ratios of: 24% chicory (Cichorium intybus L.), 30% lucerne (Medicago sativa L.), 25% plantain (Plantago lanceolata L.), and 21% ryegrass. The DMI of the MF lambs was 48% greater (P < 0.01) and the within animal day-to-day coefficient of variation (CV) of intake was 26% lower (P < 0.01) than the SF lambs. The average daily gain (ADG) of lambs offered the MF diet was 92% greater (P < 0.01) than the lambs offered the SF diet. The within animal day-to-day CV of intake was negatively related with ADG (r = -0.59: P < 0.01). The MF lamb’s urinary N concentration was 30% lower (P < 0.01) than that of the SF lambs. The SF lambs spent more time (P < 0.05) exhibiting stereotypic behaviors in the afternoon and spent more time observing other animals than the MF. Overall, allocating a multi-forage choice of fresh herbages as opposed to a single forage diet of ryegrass increases DMI and thereby animal performance, while potentially reducing urinary N excretion.

Varied diets: implications for lamb performance, rumen characteristics, total antioxidant status, and welfare

“…The DIV and VAR lambs both had greater ADG than the SFA, largely explained by differences in the nutritional composition of the diet, namely, the greater DMD and ME content of the DIV and VAR diets. Other studies have reported similar results with lower DMI from treatments offered a flavorally or biochemically uniform diet compared to those offered choice from a diverse range of feeds (Keskin et al, 2004;Atwood et al, 2006;Distel et al, 2007;Villalba et al, 2011;Garrett et al, 2021). The magnitude of the effect from choice of diverse feeds on increased DMI is lower within the present study than that reported in other studies.…”

“…Monotonous feeding environments impose nutritional repetition, which may impair animal performance and welfare. Monotonous diet presentation reduces intake or productivity relative to animals provided choice from a diverse diet (Provenza et al, 2007;Rodríguez et al, 2007;Dixon and Pasinetti, 2010;Garrett et al, 2021). This can be the result of nutrient specific satiation, as the upper threshold for a specific nutrient is reached despite deficiencies in other nutrients existing (Raubenheimer, 1992;Early and Provenza, 1998;Gregorini et al, 2017), or sensory-specific satiety, where the repeated oro-sensorial experience (i.e., taste) saturates the intake-related sensorial neurons and reduces the response for a particular feed (Early and Provenza, 1998;Epstein et al, 2009;Gregorini et al, 2017).…”

“…This can be the result of nutrient specific satiation, as the upper threshold for a specific nutrient is reached despite deficiencies in other nutrients existing (Raubenheimer, 1992;Early and Provenza, 1998;Gregorini et al, 2017), or sensory-specific satiety, where the repeated oro-sensorial experience (i.e., taste) saturates the intake-related sensorial neurons and reduces the response for a particular feed (Early and Provenza, 1998;Epstein et al, 2009;Gregorini et al, 2017). On the other hand, diverse diets that allow selectivity, enable individual animals to choose from feeds of differing nutrient and oro-sensorial profiles and can result in improved intake or performance (Villalba and Provenza, 1997;Papachristou et al, 2007;Rodríguez et al, 2007;Mote et al, 2008;Catanese et al, 2013;Garrett et al, 2021). In addition, varied diets can also improve DMI relative to repeated allocation of a single feed and specific sequences of diet allocation can improve intake relative to other sequences (Mote et al, 2008;Jensen et al, 2013).…”

“…Alfalfa was chosen to be fed in monotony and to be compared against the DIV and VAR diets as it is often used within New Zealand farming systems as a specialty finishing diet due to its ability to provide large amounts of high-quality forage (Brown et al, 2000;Avery et al, 2008;Anderson et al, 2014;Moot et al, 2019). The chosen diverse multi-forage diet increases DMI and ADG relative to a monotonous ryegrass diet (Garrett et al, 2021). Comparing this diverse diet to another species, known as a high-performing and quality diet for finishing lambs in dryland settings, will allow us to determine if the effects reported in previous work from our laboratory were diet specific.…”

Nitrogen Balance of Dairy Cows Divergent for Milk Urea Nitrogen Breeding Values Consuming Either Plantain or Perennial Ryegrass

“…Dietary and management strategies focusing on diverse swards and grazing management have been extensively explored as ways to reduce N losses [ 4 , 16 , 17 , 18 , 19 ], with the use of narrow-leaf plantain ( Plantago lanceolata L. (PL)) showing promising results for reducing total N excretions and UN concentrations in dairy cows [ 20 , 21 ]. PL is known to contain secondary bioactive compounds, such as acubin, catalpol, and acteoside [ 22 , 23 ], that have been reported to have antimicrobial and diuretic effects [ 22 , 24 ], which may influence the N partitioning of the animals.…”