Publications by authors named "P S Alvarez-Hess"
Estimating protein fractions and their degradation rate are vital to ensure optimum protein supply and degradation in the digestive system of ruminants. This study investigated the possibility of using the ANKOM gas production system and preserved rumen fluid to estimate the protein fractions and in vitro degradability of protein-rich feeds. Three in vitro methods: (1) gas production method (2) Cornell Net Carbohydrate and Protein System (CNCPS), and (3) the unavailable nitrogen assay of Ross (uN) were used to quantify protein fractions of four feeds (lupin meal, vetch grain, Desmanthus hay, and soybean meal).
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- Dry matter intake (DMI) is crucial for milk production in dairy cows, and measuring individual DMI can help optimize their diets with supplemental nutrients based on their forage intake.
- The study aimed to determine how many boli (bolus = a mass of food) cows swallow and their mass while feeding on various forages, using both direct and indirect measurement methods.
- Results showed that cows fed fresh chicory had the lowest bolus mass and highest swallowing rate, while the audio recording method was more effective in counting swallows than video recording.
Diets that contain high proportions of either wheat or supplementary fat have been individually reported to reduce enteric methane production. The objective of this research was to determine the effect of dietary fat supplementation on methane emissions and milk yield from cows fed diets containing either corn or wheat grains. It was hypothesized that cows fed a diet containing wheat would produce less methane and have lower methane yield (methane per kg of dry matter intake; MY) than cows fed a diet containing corn and that methane mitigation from fat supplementation would occur irrespective of the type of grain in the basal diet.
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- Supplementation of ruminant diets with wheat and corn affects ruminal fermentation and methane production.
- In vitro fermentation tests highlighted that the type of grain and forage-to-grain ratio of donor cows influenced methane output during fermentation of wheat and corn.
- Specifically, wheat grain reduced methane production more effectively than corn, but this difference was only noticeable when using ruminal fluid from cows that had been fed the corresponding grain type.
Background: There are several methods for estimating methane production (MP) from feedstuffs in vented in vitro systems. One method (A; 'gold standard') measures methane proportions in the incubation bottle's headspace (HS) and in the vented gas collected in gas bags. Four other methods (B, C, D and E) measure methane proportion in a single gas sample from the HS.
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