‘Rotatinuous’ stocking as a climate-smart grazing management strategy for sheep production

https://doi.org/10.1016/j.scitotenv.2020.141790Get rights and content

Highlights

  • Sward management determines lamb carcass yield and associated environmental impact.

  • Quality and production of carcass are greater in ‘Rotatinuous’ stocking approach.

  • ‘Rotatinuous’ stocking mitigate CH4 carcass intensity

  • ‘Rotatinuous’ stocking promotes feed efficiency while reducing feed costs.

  • This approach can be a wide-suitable example of climate-smart livestock production.

Abstract

We aimed to evaluate the effect of different grazing management strategies on carcass characteristics traits, meat quality and CH4 intensity and yield of lambs grazing Italian ryegrass pastures in Southern Brazil. A grazing trial was performed (2014 and 2015) in a randomized complete block design with two grazing management targets and four replicates. Treatments were traditional rotational stocking (RT), with pre- and post-grazing sward heights of 25 and 5 cm, respectively, and ‘Rotatinuous’ stocking (RN), with pre- and post-grazing sward heights of 18 and 11 cm, respectively. Castrated crossbred Texel and Polwarth lambs were used. Results indicated that diet cost per kg of dry matter (p = 0.001) and per hectare (p < 0.001) were lower for RN than for RT treatment. Final live weight (p = 0.022) and hot and cold carcass weight (p = 0.006) were greater for the RN treatment. All commercial cuts were greater for RN than for RT treatment. The RN treatment presented greater (p < 0.001) production of carcass, edible food and crude protein. Feed efficiency and feed cost conversion were better for RN than for RT treatment. CH4 intensity per kg of carcass, edible food and crude protein gain were 2.6, 2.7 and 2.1 times lower (p < 0.001) for RN. Moreover, CH4 yield was lower (p = 0.014) for RN than for RT treatment, with an average of 7.6 and 8.3% of the gross energy intake, respectively. We conclude that the ‘Rotatinuous’ stocking results in a greater carcass production, carcass quality and lower diet cost, and CH4 intensity and yield of grazing lambs. Adopting this grazing management strategy could enhance both lamb production and mitigation of CH4 intensity and yield in grazing ecosystems, which could be considered a good example of climate-smart livestock production.

Introduction

Climate change has important consequences for global agriculture production (Lipper et al., 2014). Extreme weather events, water shortages, land degradation, the disruption of ecosystems and loss of biodiversity can be expected (FAO, 2016) while agriculture systems can be significant drivers of climate change (Springmann et al., 2018).

Livestock holds the largest share in agricultural greenhouse gas (GHG) emissions, mainly because of CH4 emissions from enteric fermentation of ruminants (Gerber et al., 2013; Herrero et al., 2016). At the same time, livestock products largely contribute to human feeding (Gaughan et al., 2019), which in turn is increasing (FAO, 2017) with projection around 9.8 billion people by 2050. This scenario will drive greater demand for animal protein (Eisler et al., 2014) and could increase global CH4 emissions from livestock (IPCC, 2014). Considering that most ruminants in the world are raised in pasture-based or mixed systems, a strong emphasis must be oriented in understanding how grazing practices can impact GHG emissions, food production, biodiversity, carbon sequestration in the soils (Godde et al., 2018) and animal welfare (Llonch et al., 2017). Therefore, the challenge is developing strategies to reduce livestock's carbon footprint while increasing food production (Godfray et al., 2010).

Climate-smart approaches are proposed to achieve these goals under a global climate change scenario (Lipper et al., 2014). Henry et al. (2018) pointed out that some of the negative consequences of ruminant livestock production can be mitigated through adaptive management with improvements in animal nutrition. Many studies regarding grazing management strategies to mitigate GHG emission focus on the plant component and its ability to store carbon in the soil (Smith, 2014; Henderson et al., 2015; de la Motte et al., 2018). However, sustainable food production must also consider the ability of the animal to perform well in the grazed environment. Hence, climate-smart grazing practices should aim to maintain production levels with a reduced herd size (Herrero et al., 2016), which is possible with well-managed pastures under moderate grazing intensity (Souza Filho et al., 2019; Kunrath et al., 2020).

Thus, an innovative grazing management strategy would conciliate the trade-off of producing more animal products with fewer animals. One way to this appease was proposed by Carvalho (2013). The grazing management called ‘Rotatinuous’ stocking is based on optimum sward structure aiming to minimize the time required to achieve animals' requirements at grazing (Carvalho, 2013). It results in lower stocking rates and moderate grazing intensities, as well as greater herbage intake (i.e. animal performance) and short resting periods because of greater post-grazing sward mass. This is the opposite of the traditional rotational grazing management oriented to maximize plant growth and forage utilization efficiency by animals. In this way, Savian et al. (2018) applied ‘Rotatinuous’ stocking and reported increased in herbage intake and decreased in CH4 emissions by grazing sheep by 1.6 times per area and 2.7 times per kg of live weight (LW) gain. Similarly, Souza Filho et al. (2019)) working with temperate black-oat and Italian ryegrass mixed pastures in southern Brazil found greater animal LW gain with lower CH4 intensity (g CH4/kg LW gain).

Therefore, we hypothesized that the ‘Rotatinuous’ stocking (RN) aiming to maximize herbage intake per unit of time through offering the best sward structure results in greater carcass production, commercial cuts, meat quality and lower diet cost, carcass CH4 intensity and yield of lambs grazing Italian ryegrass (Lolium multiflorum) pastures than the conventional rotational stocking (RT).

Section snippets

Site, design and treatments

The experiment was conducted in two stocking seasons (2014 and 2015) at the Agronomic Experimental Station (EEA) of the UFRGS in Eldorado do Sul city, State of Rio Grande do Sul, Brazil (30°05′S, 51°39′W). The climate in the region is subtropical humid with the 14-year (2003–2016) mean air temperature and total rainfall (May to October) of 15.8 °C and 931 mm, respectively (EEA–UFRGS). The soil of the experimental site was classified as a Typic Paleudult with 17.5% clay, 20% silt and 62.5% sand.

Herbage characteristics

Table 1 shows the diet cots and the pre- and post-grazing sward heights according to the target proposed to this study as described by Savian et al. (2018). Diet cost per kg of DM (p = 0.001) and per hectare (p < 0.001) were lower for RN than for RT treatment. Daily diet cost per lamb was US$ 0.025 and did not differ (p = 0.461) between the treatments.

Conformation of lambs and their carcasses

Feed intake and efficiency, and carcass characteristics of lambs are shown in Table 2. The greater (p < 0.001) herbage intake per hectare for RT

Discussion

This study shows that within rotational grazing management practices, adjusting pre- and post-grazing sward height either to maximize total forage accumulation and harvest efficiency (RT) or the herbage intake per unit of time by lambs (RN), has important consequences on carcass production and quality, diet cost, CH4 intensity and yield. In the ‘Rotatinuous’ stocking scheme, lambs reached greater final LW and carcass weight (Table 3), increased production of carcass and edible food and protein

Conclusions

Our study shows that grazing management termed ‘Rotatinuous’ stocking results in a greater carcass, edible food and crude protein production, feed efficiency, better carcass quality, and lower CH4 intensity and yield of lambs grazing Italian ryegrass pastures. Therefore, this sward management strategy is a win-win solution for environmental health allowing high animal production and high mitigation of GHGs for grazing systems, that is, it is possible to reduce CH4 intensity (g/kg carcass,

CRediT authorship contribution statement

Jean Víctor Savian: conceptualization, methodology, field data collection, formal analysis, writing original draft, and writing and editing; Radael Marinho Tres Schons: field data collection, visualization, writing; William de Souza Filho: writing, review, editing; Angel Sánchez Zubieta: writing, review; Liris Kindlein: laboratory analysis, review; Jérôme Bindelle: writing, review; Cimélio Bayer: supervision, review; Carolina Bremm: review; Paulo César de Faccio Carvalho: investigation,

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

The authors thank Augusto Caetano, Emanuel Schneider, João Penso, Gentil da Silva Neto, Daniele Marchi, Jean Mezzalira and Alexandre Berndt for their valuable contributions to this work. Thanks also to Thainá Freitas for carrying out the graphical abstract. This study was financed in part by the ‘Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brasil (CAPES) and Project ‘Universal-CNPq n° 481941/2013-4’. This work was part of the PhD thesis of the first author.

References (75)

  • P. Llonch et al.

    Review: current available strategies to mitigate greenhouse gas emissions in livestock systems: an animal welfare perspective

    Animal

    (2017)
  • G. Luciano et al.

    The restriction of grazing duration does not compromise lamb meat colour and oxidative stability

    Meat Sci.

    (2012)
  • J.C. Mezzalira et al.

    Behavioural mechanisms of intake rate by heifers grazing swards of contrasting structures

    Appl. Anim. Behav. Sci.

    (2014)
  • V. Sandström et al.

    The role of trade in the greenhouse gas footprints of EU diets

    Glob. Food Sec.

    (2018)
  • J.V. Savian et al.

    Grazing intensity and stocking methods on animal production and methane emission by grazing sheep: implications for integrated crop-livestock system

    Agric. Ecosyst. Environ.

    (2014)
  • J.V. Savian et al.

    Rotatinuous stocking: a grazing management innovation that has high potential to mitigate methane emissions by sheep

    J. Clean. Prod.

    (2018)
  • J.F. Soussana et al.

    Coupling carbon and nitrogen cycles for environmentally sustainable intensification of grasslands and crop-livestock systems

    Agric. Ecosyst. Environ.

    (2014)
  • M.G. Veloso et al.

    High carbon storage in a previously degraded subtropical soil under no-tillage with legume cover crops

    Agric. Ecosyst. Environ.

    (2018)
  • J.M. Wilkinson et al.

    Review: use of human-edible animal feeds by ruminant livestock

    Animal

    (2018)
  • W. Willett et al.

    Food in the Anthropocene: the EAT–Lancet Commission on healthy diets from sustainable food systems

    Lancet

    (2019)
  • O.A. Young et al.

    A method for early determination of meat ultimate pH

    Meat Sci.

    (2004)
  • M.F. Amaral et al.

    Sward structure management for a maximum short-term intake rate in annual ryegrass

    Grass Forage Sci.

    (2013)
  • AMSA, 1967. Recommended guides for carcass evaluation and contests. American Meat Science Association, 85 p., Chicago,...
  • Barthram, G.T., 1985. Experimental techniques: the HFRO sward stick. In Biennial Report of the Hill Farming Research...
  • S. Bray et al.

    Climate clever beef: options to improve business performance and reduce greenhouse gas emissions in northern Australia

    Rangel. J.

    (2016)
  • P.C.F. Carvalho

    Harry Stobbs Memorial Lecture: can grazing behavior support innovations in grassland management?

    Trop. Grasslands

    (2013)
  • P.C.F. Carvalho et al.

    Integrating the pastoral component in agricultural systems

    Rev. Bras. Zootec.

    (2018)
  • P.C.F. Carvalho et al.

    Animal production and soil characteristics from integrated crop-livestock systems: toward sustainable intensification

    J. Anim. Sci.

    (2018)
  • Centre Internationale de L'’Eclairage

    Colorimetry (2nd Ed.)

    Vienna: Publication CIE

    (1986)
  • Z. Conrad et al.

    Relationship between food waste, diet quality, and environmental sustainability

    PLoS One

    (2018)
  • L.F. Da Silva et al.

    Crescimento de cordeiros abatidos com diferentes pesos. Osso, múlculo, e gordura da carcaça e de seus cortes. Cienc. Rural

    (2000)
  • F.D. Da Silva et al.

    Soil carbon indices as affected by 10 years of integrated crop-livestock production with different pasture grazing intensities in Southern Brazil

    Agric. Ecosyst. Environ.

    (2014)
  • J.A. Delgadillo et al.

    Alternative methods for control of reproduction in small ruminants: a focus on the needs of grazing industries

    Anim. Front.

    (2015)
  • Y. Dini et al.

    Using highly nutritious pastures to mitigate enteric methane emissions from cattle grazing systems in South America

    Anim. Prod. Sci.

    (2018)
  • B. Dumont et al.

    Review: make ruminants green again – how can sustainable intensification and agroecology converge for a better future?

    Animal

    (2018)
  • M.C. Eisler et al.

    Steps to sustainable livestock

    Nature

    (2014)
  • FAO

    Climate-smart Agriculture Sourcebook. Food and Agriculture Organization of the United Nations

    (2013)
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