Digestive, fermentative, and physical properties of pineapple residue as a feed for cattle

The intake, digestion, and ruminal fermentation properties; the antioxidative activity; and the physical effectiveness of pineapple residue (PR) from the cut-fruit industry as a feed for cattle were investigated. Four nonlactating Holstein cows were fed a basal diet and diets with 1.4- and 3.6-kg dry matter (DM)/day of PR (low-PR and high-PR diets, respectively). The DM digestibility and total digestible nutrients were 71% and 70%, respectively. Ruminal pH, volatile fatty acids, and ammonia-N did not differ among the diets. The numbers of total viable, amylolytic, cellulolytic, and methanogenic bacteria and protozoa, and microbial protein synthesis in the rumen also did not differ significantly. Blood triglyceride, nonesterified fatty acids, urea nitrogen, and aspartate transaminase were lower in the high-PR diet. Feeding PR did not affect blood malondialdehyde, although PR has a higher antioxidative value than other commonly used feeds. The particle distribution of PR satisfied the recommended range for haylage. The chewing time for ingestion and rumination did not change with PR content, and the roughage value index of PR was 57-min/kg DM. These results suggest that PR has good intake and digestion properties and satisfactory physical effectiveness. Even a high-PR-content feed unlikely induces the risk of ruminal acidosis.

Effect of physical effectiveness on digestibility of ration for cows in early lactation

A study was conducted to investigate the effects of a diet particle size on nutrient digestibility in cows in early lactation. Treatments were diets with forage to concentrate ratio 43:57% in diet dry matter, with four different physically effective fibres (peNDF) content based on different cut length of corn silage and alfalfa haylage. The physical effectiveness factors (pef) and peNDF content of TMRs (total mixed ration) were determined using Penn State Particle Separator (PSPS) with two (pef8.0 , peNDF8.0) or three (pef1.18, peNDF1.18) sieves. The reducing of cut length of forages and particle size of diets did not affect on dry matter intake, while decreased peNDF intake by 16.34 and 8.83%, for peNDF8.0 and peNDF1.18 respectively. Apparent total tract digestibility of the nutrients was measured using two indicators: acid insoluble ash (AIA) and acid detergent insoluble lignin (ADL). Decreasing of forages cut length significantly increased apparent total tract digestibility of neutral detergent fibre (NDF) from 48.39% to 53.84% and from 53.9% to 58.66%, of crude protein from 73.96% to 79.24% and from 71.56% to 77.90%, with contemporary decreasing of non-fibre carbohydrate from 90.89% to 84.81% and from 91.99% to 86.80%, with AIA or ADL as indicator respectively. Dietary value of net energy for lactation (NEL) and energy intake was not affected by the peNDF content of the diet.