Animal Production Science Animal Production Science Society
Food, fibre and pharmaceuticals from animals
RESEARCH ARTICLE

The trials and tribulations of estimating the pasture intake of grazing animals

David J. Cottle
+ Author Affiliations
- Author Affiliations

Department of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia. Email: dcottle2@une.edu.au

Animal Production Science 53(11) 1209-1220 https://doi.org/10.1071/AN13164
Submitted: 25 July 2013  Accepted: 2 September 2013   Published: 18 September 2013

Abstract

The present paper reviews estimation methods for measuring pasture intake of individual grazing animals, in particular, the use of indigestible plant markers. Natural alkanes and alcohols function essentially as an internal marker and thus accommodate differences in forage digestibility among individuals and those arising from interactions between supplement and forage. An estimate of diet composition partitions total intake into its component plant species. Estimates of diet composition require correction for incomplete faecal marker recovery, where relative recoveries (i.e. the recovery of the alkanes relative to each other) suffice. If estimates of whole-diet digestibility are also wanted, actual faecal alkane recoveries must be used. Using known labelled supplement intakes as a means of estimating the intake of all other diet components avoids the need to dose animals separately with synthetic alkanes. The results, problems and possible workarounds for a commercial system under development to estimate individual animal pasture intakes using known labelled-supplement intakes are outlined. A prototype bin system was trialled and, despite many initial technological problems, it showed enough promise for Sapien Technology to continue to develop the system with Proway Livestock.

Additional keywords: indigestible plant markers, maintenance requirements.


References

Ali HAM, Mayes RW, Lamb CS, Verma AK, Orskov ER (2004) The potential of long-chain fatty alcohols and long-chain fatty acids as diet composition markers: development of methods for quantitative analysis and faecal recoveries of these compounds in sheep fed mixed diets. The Journal of Agricultural Science 142, 71–78.
The potential of long-chain fatty alcohols and long-chain fatty acids as diet composition markers: development of methods for quantitative analysis and faecal recoveries of these compounds in sheep fed mixed diets.CrossRef | 1:CAS:528:DC%2BD2cXlsFCjsL0%3D&md5=d83d534cadb3a355c0e2bea33446abe5CAS |

Ali HAM, Mayes RW, Hector BL, Ørskov ER (2005a) Assessment of n-alkanes, long-chain fatty alcohols and long-chain fatty acids as diet composition markers: the concentrations of these compounds in rangeland species from Sudan. Animal Feed Science and Technology 121, 257–271.
Assessment of n-alkanes, long-chain fatty alcohols and long-chain fatty acids as diet composition markers: the concentrations of these compounds in rangeland species from Sudan.CrossRef | 1:CAS:528:DC%2BD2MXltVensro%3D&md5=d118882b3ae1dea82c2f6d533083ac7aCAS |

Ali HAM, Mayes RW, Hector BL, Verma AK, Ørskov ER (2005b) The possible use of n-alkanes, long-chain fatty alcohols and long-chain fatty acids as markers in studies of the botanical composition of the diet of free-ranging herbivores. The Journal of Agricultural Science 143, 85–95.
The possible use of n-alkanes, long-chain fatty alcohols and long-chain fatty acids as markers in studies of the botanical composition of the diet of free-ranging herbivores.CrossRef | 1:CAS:528:DC%2BD2MXlsF2hsLk%3D&md5=191074f6b9680e90683aaf607419e6e7CAS |

Barcia P, Bugalho MN, Campagnolo ML, Cerdeira JO (2007) Using n-alkanes to estimate diet composition of herbivores, a novel mathematical approach. Animal 1, 141–149.
Using n-alkanes to estimate diet composition of herbivores, a novel mathematical approach.CrossRef | 1:CAS:528:DC%2BD2sXotlWhtbc%3D&md5=4f70e35efd449070fa7955e97abb4b04CAS | 22444217PubMed |

Basarab JA, Toogood K, Lyle KL, Ohama V (2002) Validation of the GrowSafe® System for determining individual animal feed intake. In ‘Net feed intake in young growing cattle. Canadian Alberta Beef Industry Development Fund, Project Number, 98AB249. Final report’. pp. 13–32. Alberta Agriculture, Food and Rural Development, Lacombe Research Centre, Lacombe, AB, Canada.

Brosh A, Henkin Z, Rothman SJ, Aharoni Y, Orlov A, Arieli A (2003) Effects of n-alkane recovery in estimates of diet composition. The Journal of Agricultural Science 140, 93–100.
Effects of n-alkane recovery in estimates of diet composition.CrossRef | 1:CAS:528:DC%2BD3sXjtl2ksLc%3D&md5=89903db6422685155d8f646b48e107adCAS |

Bugalho MN, Mayes RW, Milne JA (2002) The effects of feeding selectivity on the estimation of diet composition using the n-alkane technique. Grass and Forage Science 57, 224–231.
The effects of feeding selectivity on the estimation of diet composition using the n-alkane technique.CrossRef | 1:CAS:528:DC%2BD3sXltFehsQ%3D%3D&md5=ff83788ad8c77def1936360f7b4ebbe3CAS |

Bugalho MN, Dove H, Kelman WM, Wood JT, Mayes RW (2004) Plant wax alkanes and alcohols as herbivore diet composition markers. Journal of Range Management 57, 259–268.
Plant wax alkanes and alcohols as herbivore diet composition markers.CrossRef |

Chacon E, Stobbs TH, Sandland RL (1976) Estimation of herbage consumption by grazing cattle using measurements of eating behaviour. Journal of the British Grassland Society 31, 81–87.
Estimation of herbage consumption by grazing cattle using measurements of eating behaviour.CrossRef |

Charmley E, Dove H (2007) Using plant wax markers to estimate diet composition and intakes of mixed forages in sheep by feeding a known amount of alkane-labelled supplement. Australian Journal of Agricultural Research 58, 1215–1225.
Using plant wax markers to estimate diet composition and intakes of mixed forages in sheep by feeding a known amount of alkane-labelled supplement.CrossRef | 1:CAS:528:DC%2BD2sXhsVentrbK&md5=818b12f9a5b6b476a90f79e5beb0f7eaCAS |

Chen W, Lefroy RDB, Scott JM, Blair GJ (1998) Field variations in alkane signatures among plant species in ‘degraded’ and perennial pastures on the Northern Tablelands of New South Wales. Australian Journal of Agricultural Research 49, 263–268.
Field variations in alkane signatures among plant species in ‘degraded’ and perennial pastures on the Northern Tablelands of New South Wales.CrossRef |

Costa M (1997) Toxicity and carcinogenenicity of Cr(VI) in animal models and humans. Critical Reviews in Toxicology 27, 431–442.
Toxicity and carcinogenenicity of Cr(VI) in animal models and humans.CrossRef | 1:CAS:528:DyaK2sXntVeisLw%3D&md5=2b33f14a2df424968dd874e4c615df7cCAS | 9347224PubMed |

Cottle DJ (2011) Use of residual feed intake as an indirect selection trait for reduction of methane emissions in grazing beef cattle. Proceedings of the Australasian Association of Animal Breeding and Genetics 19, 423–425.

Cottle DJ (2013) A practical system to estimate pasture intake of individual animals. Proceedings of the Australasian Association of Animal Breeding and Genetics 21, in press.

Cottle DJ, Pitchford W (In press) Production efficiency. In ‘Beef cattle production and trade’. (Eds DJ Cottle, LP Kahn) (CSIRO Publishing: Melbourne)

Cottle DJ, Nolan JV, Wiedemann SG (2011) Ruminant enteric methane mitigation: a review. Animal Production Science 51, 491–514.
Ruminant enteric methane mitigation: a review.CrossRef | 1:CAS:528:DC%2BC3MXntVGisLY%3D&md5=6c6d3a0dc4fb02456bd26bfc636b1a1bCAS |

Crews DH, Carstens GE (2012) Measuring individual feed intake and utilization in growing cattle. In ‘Feed efficiency in the beef industry’. (Ed. RA Hill) pp. 21–28. (Wiley and Blackwell: Oxford, UK)

Decandia M, Sitzia M, Cabiddu A, Kababya D, Molle G (2000) The use of polyethylene glycol to reduce the anti-nutritional effects of tannins in goats fed woody species. Small Ruminant Research 38, 157–164.
The use of polyethylene glycol to reduce the anti-nutritional effects of tannins in goats fed woody species.CrossRef |

Dixon RM, Coates DB (2009) Near infrared spectroscopy of faeces to evaluate the nutrition and physiology of herbivores. Journal of Near Infrared Spectroscopy 17, 1–31.
Near infrared spectroscopy of faeces to evaluate the nutrition and physiology of herbivores.CrossRef | 1:CAS:528:DC%2BD1MXis1ahtLk%3D&md5=1aa488415ac41b323f6f0e0f6b65dc19CAS |

Dixon RM, Coates DB (2010) Diet quality estimated with faecal near infrared reflectance spectroscopy and responses to N supplementation by cattle grazing buffel grass pastures. Animal Feed Science and Technology 158, 115–125.
Diet quality estimated with faecal near infrared reflectance spectroscopy and responses to N supplementation by cattle grazing buffel grass pastures.CrossRef | 1:CAS:528:DC%2BC3cXmvVSrsro%3D&md5=9a1ab0fe13887adf50d8ffa4ab15add5CAS |

Dixon RM, Stockdale CR (1999) Associative effects between forages and grains, consequences for feed utilization. Australian Journal of Agricultural Research 50, 757–773.
Associative effects between forages and grains, consequences for feed utilization.CrossRef |

Dove H (1992) Using the n-alkanes of plant cuticular wax to estimate the species composition of herbage mixtures. Australian Journal of Agricultural Research 43, 1711–1724.
Using the n-alkanes of plant cuticular wax to estimate the species composition of herbage mixtures.CrossRef | 1:CAS:528:DyaK3sXnvFGmtg%3D%3D&md5=77dc2590779ea36ecbc19d13da1bca20CAS |

Dove H (2010) Assessment of intake and diet composition of grazing livestock. In ‘Proceedings 4th grazing livestock nutrition conference’. (Eds BW Hess, T DelCurto, JGP Bowman, RC Waterman.) pp. 31–56. (Western Section American Society of Animal Science: Champaign, IL)

Dove H, Charmley E (2008) Using the alkanes and long-chain alcohols of plant cuticular wax to estimate diet composition and the intakes of mixed forages in sheep consuming a known amount of alkane-labelled supplement. Animal 2, 1474–1485.
Using the alkanes and long-chain alcohols of plant cuticular wax to estimate diet composition and the intakes of mixed forages in sheep consuming a known amount of alkane-labelled supplement.CrossRef | 1:CAS:528:DC%2BD1MXitVWitrw%3D&md5=27f6910bfba9cc03baf95b0ff7e1199cCAS | 22443905PubMed |

Dove H, Mayes RW (1991) The use of plant wax alkanes as marker substances in studies of the nutrition of herbivores: a review. Australian Journal of Agricultural Research 42, 913–952.
The use of plant wax alkanes as marker substances in studies of the nutrition of herbivores: a review.CrossRef | 1:CAS:528:DyaK3MXmsFCku78%3D&md5=a7b9a0c8e9d07099f283f908af4e04f9CAS |

Dove H, Mayes RW (1996) Plant wax components: a new approach to estimating intake and diet composition in herbivores. The Journal of Nutrition 126, 13–26.

Dove H, Mayes RW (2005) Using n-alkanes and other plant wax components to estimate intake, digestibility and diet composition of grazing/browsing sheep and goats. Small Ruminant Research 59, 123–139.
Using n-alkanes and other plant wax components to estimate intake, digestibility and diet composition of grazing/browsing sheep and goats.CrossRef |

Dove H, Mayes RW (2006) Protocol for the analysis of n-alkanes and other plant-wax compounds and for their use as markers for quantifying the nutrient supply of large mammalian herbivores. Nature Protocols 1, 1680–1697.
Protocol for the analysis of n-alkanes and other plant-wax compounds and for their use as markers for quantifying the nutrient supply of large mammalian herbivores.CrossRef | 1:CAS:528:DC%2BD2sXhtFagtrfE&md5=8e12fae197253e5f473081b527b109baCAS | 17487151PubMed |

Dove H, Moore AD (1995) Using a least-squares optimisation procedure to estimate botanical composition based on the alkanes of plant cuticular wax. Australian Journal of Agricultural Research 46, 1535–1544.
Using a least-squares optimisation procedure to estimate botanical composition based on the alkanes of plant cuticular wax.CrossRef | 1:CAS:528:DyaK28XhtFylsLY%3D&md5=a7aa78ed401dd1e80cb498f6d20591c9CAS |

Dove H, Oliván M (1998) Using synthetic or beeswax alkanes for estimating supplement intake in sheep. Animal Production Australia 22, 189–192.

Dove H, Mayes RW, Freer M (1996) Effects of species, plant part and age on the n-alkane concentrations in the cuticular wax of pasture plants. Australian Journal of Agricultural Research 47, 1333–1347.
Effects of species, plant part and age on the n-alkane concentrations in the cuticular wax of pasture plants.CrossRef | 1:CAS:528:DyaK28XntVChtrw%3D&md5=91b58ac188c712e4acc614fb16ee688eCAS |

Dove H, Wood JT, Simpson RJ, Leury BJ, Gatford KL, Siever-Kelly C, Ciavarella TA (1999) Spray-topping annual grass pasture with glyphosate to delay loss of feeding value during summer. III. Quantitative basis of the alkane-based procedures for estimating diet selection and herbage intake by grazing sheep. Australian Journal of Agricultural Research 50, 475–485.
Spray-topping annual grass pasture with glyphosate to delay loss of feeding value during summer. III. Quantitative basis of the alkane-based procedures for estimating diet selection and herbage intake by grazing sheep.CrossRef | 1:CAS:528:DyaK1MXjslyjsLw%3D&md5=9f93efda31e3948405fb36d522611493CAS |

Dove H, Freer M, Foot JZ (2000) The nutrition of grazing ewes during pregnancy and lactation, a comparison of alkane-based and chromium/in vitro based estimates of herbage intake. Australian Journal of Agricultural Research 51, 765–777.
The nutrition of grazing ewes during pregnancy and lactation, a comparison of alkane-based and chromium/in vitro based estimates of herbage intake.CrossRef | 1:CAS:528:DC%2BD3cXmtFKjt74%3D&md5=7eeaff5fc15b6f8c212f384bd6923ec0CAS |

Dove H, Mayes RW, Lamb CS, Ellis KJ (2002) Factors influencing the release rate of alkanes from an intra-ruminal, controlled-release device, and the resultant accuracy of intake estimation in sheep. Australian Journal of Agricultural Research 53, 681–696.
Factors influencing the release rate of alkanes from an intra-ruminal, controlled-release device, and the resultant accuracy of intake estimation in sheep.CrossRef | 1:CAS:528:DC%2BD38Xlt1Clurk%3D&md5=449bcb82ee472a33e88401d94e47b106CAS |

Eglinton G, Hamilton RJ (1967) Leaf epicuticular waxes. Science 156, 1322–1335.
Leaf epicuticular waxes.CrossRef | 1:CAS:528:DyaF2sXks1Wmtbo%3D&md5=c922527d787e6c00682dcf89d5c1bbabCAS | 4975474PubMed |

Elwert C, Dove D (2005) Estimation of roughage intake in sheep using a known daily intake of a labelled supplement. Animal Science 81, 47–56.
Estimation of roughage intake in sheep using a known daily intake of a labelled supplement.CrossRef | 1:CAS:528:DC%2BD2MXhtVWqt7rE&md5=17cf3436e72aa0ae92b9cff9cb9ce49dCAS |

Ferreira LMM, Oliván M, Rodrigues MAM, Osoro K, Dove H, Dias-da-Silva A (2004) Estimation of feed intake by cattle using controlled-release capsules containing n-alkanes or chromium sesquioxide. The Journal of Agricultural Science 142, 225–234.
Estimation of feed intake by cattle using controlled-release capsules containing n-alkanes or chromium sesquioxide.CrossRef | 1:CAS:528:DC%2BD2cXptFyju7Y%3D&md5=5dc691479037f116196b757cbf413d1cCAS |

Ferreira LMM, Garcia U, Rodrigues MAM, Celaya R, Dias-da-Silva A, Osoro K (2007) The application of the n-alkane technique for estimating the composition of diets consumed by equines and cattle feeding on upland vegetation communities. Animal Feed Science and Technology 138, 47–60.
The application of the n-alkane technique for estimating the composition of diets consumed by equines and cattle feeding on upland vegetation communities.CrossRef | 1:CAS:528:DC%2BD2sXhtFSlu7%2FL&md5=f05d31884ef6be02c32c74c3b6c2c3cfCAS |

Ferreira LMM, Carvalho S, Falco V, Celaya R, García U, Santos AS, Rodrigues MAM, Osoro K (2009a) Assessment of very long-chain fatty acids as complementary or alternative natural faecal markers to n-alkanes for estimating diet composition of goats feeding on mixed diets. Journal of Animal Science 87, 2732–2745.
Assessment of very long-chain fatty acids as complementary or alternative natural faecal markers to n-alkanes for estimating diet composition of goats feeding on mixed diets.CrossRef | 1:CAS:528:DC%2BD1MXptV2gtLc%3D&md5=67f39644368b575385228fdedb0c4eb7CAS |

Ferreira LMM, Celaya R, García U, Rodrigues MAM, Osoro K (2009b) Differences between domestic herbivores species in alkane faecal recoveries and the accuracy of subsequent estimates of diet composition. Animal Feed Science and Technology 151, 128–142.
Differences between domestic herbivores species in alkane faecal recoveries and the accuracy of subsequent estimates of diet composition.CrossRef |

Ferreira LMM, Celaya R, Falco V, Oliván M, Santos AS, Guedes C, Rodrigues MAM, Osoro K (2010) Evaluation of very long-chain fatty acids and n-alkane epicuticular compounds as markers for estimating diet composition of sheep fed heathland vegetation species. Animal Feed Science and Technology 156, 75–88.
Evaluation of very long-chain fatty acids and n-alkane epicuticular compounds as markers for estimating diet composition of sheep fed heathland vegetation species.CrossRef | 1:CAS:528:DC%2BC3cXjtVCksr8%3D&md5=646e49cbe17a9cfb23f6aba52272790eCAS |

Fraser MD, Theobald VJ, Moorby JM (2006) Determining diet composition on complex swards using n-alkanes and long-chain fatty alcohols. Ecological Applications 16, 1901–1910.
Determining diet composition on complex swards using n-alkanes and long-chain fatty alcohols.CrossRef | 1:STN:280:DC%2BD28njtlehug%3D%3D&md5=cc18ebbb398389551be967c7440c3c98CAS | 17069381PubMed |

Grace ND, Body DR (1981) The possible use of long-chain (C19–C32) fatty acids in herbage as an indigestible faecal marker. The Journal of Agricultural Science 97, 743–745.
The possible use of long-chain (C19–C32) fatty acids in herbage as an indigestible faecal marker.CrossRef | 1:CAS:528:DyaL38XhsVWmu7o%3D&md5=9eafd285971847dbce7e768ca919930cCAS |

Hameleers A, Mayes RW (1998) The use of n-alkanes to estimate herbage intake and diet composition by dairy cows offered a perennial ryegrass/white clover mixture. Grass and Forage Science 53, 164–169.
The use of n-alkanes to estimate herbage intake and diet composition by dairy cows offered a perennial ryegrass/white clover mixture.CrossRef | 1:CAS:528:DyaK1cXmtFWlsr4%3D&md5=690149988d2264dd68a0879c26b4b48eCAS |

Hanley TA (1982) The nutritional basis for food selection by ungulates. Journal of Range Management 35, 146–151.
The nutritional basis for food selection by ungulates.CrossRef |

Keli A, Andueza D, de Vega A, Guada JA (2008) Validation of the n-alkane and NIRS techniques to estimate intake, digestibility and diet composition in sheep fed mixed lucerne, ryegrass diets. Livestock Science 119, 42–54.
Validation of the n-alkane and NIRS techniques to estimate intake, digestibility and diet composition in sheep fed mixed lucerne, ryegrass diets.CrossRef |

Kelman WM, Bugalho MN, Dove H (2003) Cuticular wax alkanes and alcohols used as markers to estimate the diet composition of sheep (Ovis aries). Biochemical Systematics and Ecology 31, 919–927.
Cuticular wax alkanes and alcohols used as markers to estimate the diet composition of sheep (Ovis aries).CrossRef | 1:CAS:528:DC%2BD3sXktFGjsrs%3D&md5=09dcd4ecb74b6f398d1c1eeea4f7df02CAS |

Langlands JP (1987) Assessing the nutrient status of herbivores. In ‘The nutrition of herbivores’. (Eds JB Hacker, JH Ternouth) pp. 363–390. (Academic Press: Sydney)

Lin LJ, Luo HL, Wang H, Zhang YJ, Shu B (2009) Evaluation of long-chain alcohols and fatty acids, in combination with alkanes, as markers in the estimation of the composition of four herbages in mixtures. Grass and Forage Science 64, 19–25.
Evaluation of long-chain alcohols and fatty acids, in combination with alkanes, as markers in the estimation of the composition of four herbages in mixtures.CrossRef | 1:CAS:528:DC%2BD1MXktFGgtbs%3D&md5=7420c8b16836186f5aa822b80fa4fffbCAS |

Mayes RW, Dove H (2000) Measurement of dietary nutrient intake in free-ranging mammalian herbivores. Nutrition Research Reviews 13, 107–138.
Measurement of dietary nutrient intake in free-ranging mammalian herbivores.CrossRef | 1:CAS:528:DC%2BD3cXlvVaksbY%3D&md5=6cd5aebd28bb128c2f41dc609fb32360CAS | 19087435PubMed |

Mayes RW, Dove H (2004) Satellite meeting, wild and domestic herbivore diet characterization. In ‘Manual of methods accompanying, wild and domestic herbivore diet characterization. Satellite meeting to the 6th international symposium on the nutrition of herbivores, Merida, Mexico, October 2003’. (Nottingham University Press: Nottingham, UK)

Mayes RW, Lamb CS, Colgrove PM (1986) The use of dosed and herbage n-alkanes as markers for the determination of herbage intake. The Journal of Agricultural Science 107, 161–170.
The use of dosed and herbage n-alkanes as markers for the determination of herbage intake.CrossRef | 1:CAS:528:DyaL28XlsFajs7k%3D&md5=933c49acb9dc38c476fc9d7bff015370CAS |

Mayes RW, Beresford NA, Lamb CS, Barnett CL, Howard BJ, Jones B-EV, Eriksson O, Hove K, Pedersen O, Staines BW (1994) Novel approaches to the estimation of intake and bioavailability or radiocaesium in ruminants grazing forested areas. The Science of the Total Environment 157, 289–300.
Novel approaches to the estimation of intake and bioavailability or radiocaesium in ruminants grazing forested areas.CrossRef | 1:CAS:528:DyaK2MXisFekt78%3D&md5=bf3e443f9d397669283136fc50bb11c3CAS | 7839116PubMed |

Minson DJ, McDonald CK (1987) Estimating forage intake from the growth of cattle. Tropical Grasslands 21, 116–122.

Molle G, Decandia M, Dove H (1998) A comparison between different procedures for dosing n-alkanes to sheep. In ‘Proceedings of the IX European intake workshop, IGER, North Wyke, Devon, UK’, pp. 53–57.

Morais JAS, Berchielli TT, de Vega A, Queiroz MFS, Keli A, Reis RA, Bertipaglia LMA, Souza SF (2011) The validity of n-alkanes to estimate intake and digestibility in Nellore beef cattle fed a tropical grass (Brachiaria brizantha cv. Marandu). Livestock Science 135, 184–192.
The validity of n-alkanes to estimate intake and digestibility in Nellore beef cattle fed a tropical grass (Brachiaria brizantha cv. Marandu).CrossRef |

Moshtagi Nia SA, Wittenberg KM (2002) Evaluation of n-alkanes as markers for estimation of dry matter intake and digestibility in steers consuming all-forage or concentrate-forage diets. Canadian Journal of Animal Science 82, 419–425.
Evaluation of n-alkanes as markers for estimation of dry matter intake and digestibility in steers consuming all-forage or concentrate-forage diets.CrossRef |

Newman JA, Thompson WA, Penning PD, Mayes RW (1995) Least-squares estimation of diet composition from n-alkanes in herbage and faeces using matrix mathematics. Australian Journal of Agricultural Research 46, 793–805.
Least-squares estimation of diet composition from n-alkanes in herbage and faeces using matrix mathematics.CrossRef | 1:CAS:528:DyaK2MXosFelsLs%3D&md5=5d258bed76c1814d70f35a47ec4077f3CAS |

Oliván M, Ferreira LMM, Celaya R, Osoro K (2007) Accuracy of the n-alkane technique for intake estimates in beef cattle using different sampling procedures and feeding levels. Livestock Science 106, 28–40.
Accuracy of the n-alkane technique for intake estimates in beef cattle using different sampling procedures and feeding levels.CrossRef |

Oró J, Nooner DW, Wikström SA (1965) Paraffinic hydrocarbons in pasture plants. Science 147, 870–873.
Paraffinic hydrocarbons in pasture plants.CrossRef | 17793563PubMed |

Parker WJ, Morris ST, Garrick DJ, Vincent GL, McCutcheon SN (1990) Intraruminal chromium controlled release capsules for measuring herbage intake in ruminants – a review. Proceedings of the New Zealand Society of Animal Production 50, 437–442.

Paull D, Geenwood P, Valencia P, Overs L, Trotter M, Purvis I (2012) Development and application of real-time sensors for enhancing productivity and efficiency at pasture. In ‘Proceedings of the 3rd Australian and New Zealand spatially enabled livestock management symposium, Lincoln University, Lincoln, New Zealand, 6 July 2012’. (Ed. K Betteridge) pp. 18–19. (AgResearch Grasslands: Palmerston North, New Zealand)

PCT/AU2010/001054 (2010) System and method for monitoring the feeding practices of individual animals in a grazing environment (WO2011020145). Available at https://www.google.com/patents/WO2011020145A1 [Verified 4 September 2013]

Piasentier E, Bovolenta S, Malossini F (2000) The n-alkane concentrations in buds and leaves of browsed broadleaf trees. The Journal of Agricultural Science 135, 311–320.
The n-alkane concentrations in buds and leaves of browsed broadleaf trees.CrossRef | 1:CAS:528:DC%2BD3cXoslGltL4%3D&md5=a5adaa215f2ac9f287df15be33765624CAS |

Smith LL, Strickland JR (2007) Improved GC/MS method for quantitation of n-alkanes in plant and faecal material. Journal of Agricultural and Food Chemistry 55, 7301–7307.
Improved GC/MS method for quantitation of n-alkanes in plant and faecal material.CrossRef | 1:CAS:528:DC%2BD2sXptVWksLw%3D&md5=b0849939d674cfb881c409b9bfeff46fCAS | 17696447PubMed |

Smith DG, Mayes RW, Raats JG (2001) Effect of species, plant part, and season of harvest on n-alkane concentrations in the cuticular wax of common rangeland grasses from southern Africa. Australian Journal of Agricultural Research 52, 875–882.
Effect of species, plant part, and season of harvest on n-alkane concentrations in the cuticular wax of common rangeland grasses from southern Africa.CrossRef | 1:CAS:528:DC%2BD3MXntlaru70%3D&md5=e778b0eb3dc2107ff131da79985d397bCAS |

Titgemeyer EC, Armendariz CK, Bindel DJ, Greenwood RH, Loest CA (2001) Evaluation of titanium dioxide as a digestibility marker in cattle. Journal of Animal Science 79, 1059–1063.

Vogts A, Moossen H, Rommerskirchen F, Rullkötter J (2007) Molecular isotopic composition and distribution patterns of long-chain n-alkanes and n-alkanols from C3 plants growing in different tropical habitats. Available at www.ogc.icbm.de/poster/Paleoceanography/Vogts_2007-IMOG_Torquay_molecular-isotopic-composition.pdf. [Verified 4 September 2013]

Zehner N, Niederhauser JJ, Nydegger F, Grothmann A, Keller M, Hoch M, Haeussermann A, Schick M (2012) Validation of a new health monitoring system (RumiWatch) for combined automatic measurement of rumination, feed intake, water intake and locomotion in dairy cows. In ‘Proceedings of international conference of agricultural engineering CIGR-Ageng 2012. C0438, Valencia, Spain’. pp. 1–6. Available at http //cigr.ageng2012.org/images/fotosg/tabla_137_C0438.pdf [Verified 4 September 2013]



Rent Article (via Deepdyve) Export Citation Cited By (11)