Rumen escape protein in grass and grass silage determined with a nylon bag and an enzymatic technique

Cone, J.W.; Gelder, A.H. van; Mathijssen-Kamman, A.A.; Hindle, V.A.

doi:10.1016/j.anifeedsci.2003.08.004

Cited by 14 publications

(12 citation statements)

References 14 publications

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“…This is likely due to increasing the cell wall-associated protein fractions (B2+C) that are characterized by limited ruminal degradability or are completely undegradable (Higgs et al, 2015). Our findings are in the range reported by Cone et al (2004) for rumen undegradable protein in different grass samples after 3 weeks of the regrowth period (23.1-37.4 or 34.9% CP) and by Grabber (2009) for RUP in herbage of different legume species (25.6-33.2% CP).…”

Section: Resultssupporting

confidence: 66%

Protein degradability of grassland forage under simulated rotational spring grazing

et al. 2019

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A cutting experiment was conducted to analyze the changes in the crude protein (CP) fraction content and in the estimated ruminal protein degradability of forage, obtained in conditions of simulated rotational spring grazing on permanent grassland. The field trial was conducted on permanent pasture during 2015 and included three cuttings as a simulated rotational spring grazing. For determination of protein degradability of pasture forage, the fractionation of the CP according to Cornell Net Carbohydrate and Protein System (CNCPS v6.5) and the Streptomyces griseus protease assay were used. Relative to CP, no significant differences were found among cuts for ammonia N content (A1 fraction) and for protein fraction C which is completely unavailable to the animals. Values for soluble true protein (A2 fraction) and cell wall-associated protein, which is acid detergent soluble (B2), were significantly increased (p<0.05) while a significant reduction (p<0.05) of the moderately degradable protein (B1) content was determined during the growing season. The lower rumen degradable protein (RDP) content of grassland herbage was obtained in the second cut which was significant (p<0.05) according to the CNCPS procedure. Obtained high solubility and degradability of CP in pasture require adequate content of readily available carbohydrates in rations for grazing ruminants to provide efficient utilization of consumed protein.

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Section: Resultssupporting

confidence: 66%

Protein degradability of grassland forage under simulated rotational spring grazing

et al. 2019

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“…Van Soest (1991) has suggested that lag time may be an artefact much influenced by the laboratory techniques used, but that there would be no strong evidence of occurrence under in vivo rumen conditions. The dacron bags used in the in situ method have been subjected to several criticisms due to difficulty or easiness of the feed sample and microbes to enter and leave the bags across the membrane (Mathis et al, 2001;Cone et al, 2004) This may well be one reason for creating lag times during the experiments. The lack of lag time during incubation with REE should be related with a good enzymatic activity, a non limiting enzyme-substrate affinity, a high enzyme/substrate ratio, as well as being helped by the small particle size resulting from sample grinding prior to incubation.…”

Section: Discussionmentioning

confidence: 99%

“…The quantitative assessment of the breakdown process is key to carry out an effective and sustainable nutrition of the productive ruminants (Givens et al, 2000;Monteny, 2000, quoted by Van Duinkerken et al, 2005. The in situ technique developed by Mehrez and Ørskov (1977) is widely used to study the protein breakdown of the feeds in the rumen, nevertheless, several criticisms have weakened the merits that were originally assigned to this methodology, forcing several corrections needed to adjust the data according to their sources of error (Mathis et al, 2001;Cone et al, 2004). Research has also been developed on the proteins degradability with commercial enzymes (Pichard and Van Soest, 1977;Assoumani et al, 1992), where proteases from Streptomyces griseus fungus have been used, reaching satisfactory levels of proteins breakdown.…”

Section: Introductionmentioning

confidence: 99%

In vitro protein breakdown by enzyme extracts of rumen origin: comparison with methods in situ and proteases of Streptomyces griseus

Velásquez

Pichard

2010

Cienc. Inv. Agr.

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A. Velásquez, and G. Pichard. 2010. In vitro protein breakdown by enzyme extracts of rumen origin: comparison with methods in situ and proteases of Streptomyces griseus. Cien. Inv. Agr. 37(3): 57-70. Proteolytic activity of enzymatic extracts generated from rumen microorganisms cultivated in vitro was evaluated. The incubation of rumen fluid used different substrates to generate a higher enzyme concentration and promote a broad spectrum of hydrolytic activity. The composition of the substrates used in the cultivation of the fluid was enriched in protein, starch or cell wall. Enzyme preparations were evaluated by incubating in 30 mL of buffer 50 mM Tris-HCl (pH 6.5) at 39 ºC during 48 hours, 100 mg of crude protein from feeds soybean meal, canola meal, sunflower meal, gluten feed, dehydrated alfalfa meal, berseem clover, oat forage and perennial ryegrass. Enzyme extracts from cultivated rumen fluid showed an average protein breakdown of 75.5%, in eight feed samples tested. This value was very close to that measured with the technique of proteases from Streptomyces griseus (74.6% CP), but significantly lower (P≤0.05) than the one obtained by the in situ methodology (84.8% CP). The technique with extracted rumen enzymes showed higher level of proteolysis in the early hours of incubation (6 H) compared to the other techniques. These results suggest that the enzyme preparations of ruminal origin have the ability to predict degradability of feed proteins in the rumen, particularly in the first phase when most of proteins are hydrolyzed and become available for microbial utilization.

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“…Its principal merit is the incubation protocol, which is directly applied in the ruminal ecosystem and is the protocol that is most frequently used today thus providing an important reference for the validation of alternative methods. It has been criticized, however, for the presence of various disturbing effects, the most important of which are microbial and N-compound contamination in the residue bags, the escape of particles from the bags into the ruminal medium, and the rarefication of the environment inside the bags (Mathis et al, 2001;Cone et al, 2004). One possibility for correcting particle loss from the bags into the ruminal medium is the method developed by Velásquez and Pichard (2010b) and modified from Weisbjerg et al (1996), which states that the corrected b fraction (bc) = b + P (b (1-(P + SN)) -1 ), where b is the nitrogenous fraction enzymatically degraded in situ (corrected, in turn, for microbial contamination); P is the particle loss from the bag into the ruminal medium; and SN is the soluble nitrogen.…”

Section: Methodologies For Predicting Protein Degradability In the Rumenmentioning

confidence: 99%

“…The kinetics of protein degradation in the ruminal ecosystem are affected by complex interactions between biotic and abiotic components resulting in biological conditions that are difficult to simulate with great accuracy or precision; there is great variability among observations made using in vitro, in situ or in vivo methods (Stern et al, 1994;Broderick et al, 2004;Cone et al, 2004;Habib et al, 2013;Hao et al, 2016). The most important biological components are related to the biodiversity and ecological behavior of the microorganisms in the rumen, principally their bioenergetic, enzymatic and hydrolytic processes and they synthesis of microbial proteins.…”

Section: Complexity Of Proteolysis In the Ruminal Ecosystemmentioning

confidence: 99%

Empirical Attributes and Limitations of Methodologies for Predicting the Degradability of Ruminal Protein

2016

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present review is to analyze the methodologies that are commonly used to estimate protein degradability in the rumen, focusing on their attributes and limitations to offer suggestions for improving their use. This information is essential for selecting food types when formulating feed diets. A reliable prediction of the digestibility of ruminal proteins is basic information necessary for optimizing the use of nitrogenous sources because digestibility can translate, on the one hand, into higher yields of milk, milk protein, meat or wool and, on the other hand, into lower excretion of nitrogenous compounds into the environment; it also has an impact on animal health and welfare. Traditionally, the digestibility of feed proteins in the rumen has been predicted by in vivo, in situ and in vitro methods, but other techniques based on infrared spectroscopy have been developed, notably the NIRS and FTIR methods. All of these techniques present limitations, such as a disturbance factor or a source of error, that may result in inaccurate predictions. The in situ and in vitro methods, which use enzyme extracts of ruminal origin, and FTIR probably have the greatest advantages, but they need to be perfected through further research.

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Rumen escape protein in grass and grass silage determined with a nylon bag and an enzymatic technique

Cited by 14 publications

References 14 publications

Protein degradability of grassland forage under simulated rotational spring grazing

Protein degradability of grassland forage under simulated rotational spring grazing

In vitro protein breakdown by enzyme extracts of rumen origin: comparison with methods in situ and proteases of Streptomyces griseus

Empirical Attributes and Limitations of Methodologies for Predicting the Degradability of Ruminal Protein

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