Evaluation of external markers to estimate fecal excretion, intake, and digestibility in dairy cows

Abstract

The objective of this study was to compare the use of an external marker titanium dioxide (TiO₂) as an alternative to chromic oxide (Cr₂O₃) in dairy cows. Four dairy cows were allocated in individual pens and fed concentrate supplement and Pennisetum purpureum cv. Cameroon cut daily. Fecal excretion, forage and total dry matter (DM) intakes, and digestibility were measured and estimated with TiO₂ and Cr₂O₃. Chromic oxide overestimated and TiO₂ tended to overestimate fecal excretion compared with total fecal collection. Forage and total DM intakes were overestimated by Cr₂O₃. The apparent DM digestibility was underestimated by Cr₂O₃ and TiO₂. The organic matter (OM) digestibility was underestimated by both markers. There were greater mean bias, mean squared prediction error, and root of the mean squared prediction errors for all parameters estimated with Cr₂O₃. In conclusion, estimates using TiO₂ were more precise and accurate indicating that it can replace Cr₂O₃ as an external marker for grazing dairy cows.

Effect of concentrate level on enteric methane emissions, production performance, and rumen fermentation of Jersey cows grazing kikuyu-dominant pasture during summer

“…Fecal samples were immediately oven-dried (65°C, 72 h), pooled within animal, and analyzed for TiO 2 concentration by the method of Myers et al (2004). Fecal output was calculated from the daily TiO 2 dose and TiO 2 concentration in feces as described by de Souza et al (2015).…”

Use of indigestible markers to estimate the apparent dry matter digestibility of diets containing a cocoa by-product

“…Glindemann et al (2009) found that FP and the recovery of TD were similar to those obtained by TC; moreover, TD recovery was higher in diets containing hay alone compared to diets containing hay and concentrate, and fecal excretion was improved when the indicator was administered once daily and FC was performed twice daily. Similarly, Souza et al (2015) evaluated using TD as an alternative to CO for estimating FP and ADMD and observed that CO overestimated FP and the results for these two parameters were more accurate using TD. Moreira Filho et al (2017) indicated that CO, TD, and IDM were effective in estimating FP and ADMD, with correlation coefficients higher than 90% relative to TC.…”

Estimación de excreción fecal en alpacas (Vicugna pacos) bajo condiciones estabuladas usando dióxido de titanio

“…Los tratamientos fueron: T2.5(1), 2.5 g de TiO 2 /animal/día; T1.25(2), 2.5 g de TiO 2 /animal/día repartido en dos dosis (07:00, 16:00); T5(1), 5 g de TiO 2 /animal/día; T2.5(2), 5 g de TiO 2 /animal/día repartido en dos dosis (07:00, 16:00). Los porcentajes de la recuperación de TiO 2 fueron de 90, 82, 78 y 52% para T2.5(1), T1.25 (2), T5(1) y T2.5 (2), respectivamente, siendo T2. 5(2) diferente a los otros tratamientos (p=0.00013).…”

“…Estimation of faecal excretion in alpacas (Vicugna pacos) in confinement conditions using titanium dioxide Rosina Camargo H. 1 , Carlos Vílchez P. 2 , Juan Olazábal L. 1 , Felipe San Martín H. 1…”