Factors Affecting the Nutritive Value of Grass Silages

Thomas, Chris

doi:10.1016/b978-0-407-01164-9.50021-2

Cited by 22 publications

(12 citation statements)

References 80 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Extensive research has been undertaken on this subject (Shaver et al, 1985;Gill et al, 1988; Thomas and Thomas, 1988). In several studies neutralization did lead to higher silage intake Shaver et al, 1985;Erdman, 1988;Ndwiga et al, 1990), but in other studies no effect was observed (Wilkins, 1974;Fahran and Thomas, 1978;Snyder et al, 1983;Phillip and Hidalgo, 1989).…”

Section: Oropharyngeal Levelmentioning

confidence: 99%

Control of voluntary intake of precision-chopped silages by ruminants: a review

Dulphy¹,

Os²

1996

Reprod. Nutr. Dev.

View full text Add to dashboard Cite

Summary ― The aim of this review is to provide a better understanding of the ways in which ruminants control their voluntary intake of finely-chopped silages. Silages with an excellent conservation quality can be ingested at similar levels to the corresponding fresh or dry forages. Intake levels decrease when conservation quality decreases. The implicated physiological mechanisms for this phenomenon are discussed in this review. Poorly preserved silages may have low palatibility, decreasing the animal's motivation to ingest. At the ruminal level, the physical control of intake is generally not involved. On the other hand the fermentation products present in silage seem to induce a high and rapid level of satiation, out of proportion to their relatively low quantity. At the metabolical level some limiting factors may also exist (eg, a poor balance between amino acids and energy, and high levels of acids to be metabolized). Fermentation products induce most of the observed reactions. For well-preserved silages, high quantities of lactic and acetic acids limit intake. Their effects seem to be additive, which explains the observation that low pH often has a negative action. The negative effect of moisture is generally strengthened by that of the acids. For poorly-preserved silages, products of protein decomposition must be considered in addition to volatile fatty acids. The effect of N-compounds is less clearly explained than that of acids. For example, ammonia alone generally seems to have no direct effect. However it is clear that N-compounds taken together have a negative effect on appetite. It can be concluded that the negative effects of poor quality silages are multifactorial; each fermentation product alone has a low effect, but the sum of all the components must be considered. Moreover, it is apparent that some physiological mechanisms are used to control silage intake, which explains the complexity of the studies on this subject.

show abstract

Section: Oropharyngeal Levelmentioning

confidence: 99%

Control of voluntary intake of precision-chopped silages by ruminants: a review

Dulphy¹,

Os²

1996

Reprod. Nutr. Dev.

View full text Add to dashboard Cite

show abstract

“…It was shown that under these conditions lysine was clearly the first limiting amino acid and methionine a colimiting one (Rulquin et al, 1993;Sloan, 1997). Conversely, a major nutritional limitation inherent in grass silage-based diets seems to be an insufficient supply of methionine (Thomas and Thomas, 1985;Thomas and Rae, 1988). Interestingly, the determined proportion of these amino acids in the sum of total amino acids determined in the small intestine of cows fed grass silage (Teller et al, 1992;Harrison et al, 1994;Holden et al, 1994), were apparently below the optimum requirement value for methionine (i.e.…”

Section: Introductionmentioning

confidence: 99%

The effect of protected methionine on milk yield and its composition in lactating dairy cows fed grass silage-based diets

Pisulewski¹,

Kowalski²

1999

J. Anim. Feed Sci.

View full text Add to dashboard Cite

Five muciparous Polish Red-and-White cows (in wk 8-12 of lactation) were assigned to a 5 x 5Latin square design and fed total mixed ration TMR containing grass silage and concentrates representing 58 and 42% of dietary DM, respectively. The five treatments were dietary supplements of protected DL-methionine (Smartamine™ M) fed in the following amounts: 0, 8, 16, 24 and 32 g/d.Dry matter intake yield milk, milk protein and fat, and contents of protein, fat and lactose in milk were not affected by the treatments. At the same time, NPN (%) was significantly affected (P<0.01), and protein-N and NPN (% of total-N) responded in an opposite manner (P<0.05). Of the plasma metabolites studied ((3-hydroxybutyrate, glucose, and urea), only glucose levels were significantly (P<0.01) decreased by methionine supplementation. Plasma free methionine was significantly elevated (P<0.01) over the five treatments. In conclusion, the lack of apparent changes in the studied responses could have been due either to a higher methionine supply than that predicted or to a lower methionine requirement than that assumed. Consequently, a consistent relationship between increasing amounts of Smartamine™ M (0, 8, 16, 24, and 32 g/d) and milk protein responses of the cows, could not be described.

show abstract

“…The fermentation processes in the short term were influenced by wilting with a slower development taking place in the wilted silages. The [12,15,21].…”

mentioning

confidence: 99%

Wilting effect on fermentation characteristics and nutritive value of mountain permanent meadow grass silage

Xiccato¹,

Bini²,

Carazzolo³

et al. 1998

Ann. Zootech.

View full text Add to dashboard Cite

-Grass from a pre-alpine permanent meadow located in the Cansiglio Highland (north Italy) was ensiled immediately after harvesting (TOO), and after 5 h (TOS) and 26 h (T26) of wilting. Two types of experimental silos were used to assess the chemical characteristics and the evolution of fermentation processes in pre-wilted silages: 500 L capacity silos (S500), opened after 6 months, and 2 L mini-silos (S002), opened at different times after ensiling (0, 12, 24, 48, 96 and 192

show abstract

Factors Affecting the Nutritive Value of Grass Silages

Cited by 22 publications

References 80 publications

Control of voluntary intake of precision-chopped silages by ruminants: a review

Control of voluntary intake of precision-chopped silages by ruminants: a review

The effect of protected methionine on milk yield and its composition in lactating dairy cows fed grass silage-based diets

Wilting effect on fermentation characteristics and nutritive value of mountain permanent meadow grass silage

Contact Info

Product

Resources

About