Effect of three different forage to concentrate ratios on average daily gain and ruminal health in growing dairy heifers.
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2018-12
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Universidad EARTH
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El objetivo de este estudio fue determinar el efecto de tres proporciones de forraje:concentrado (F: C) en el crecimiento de novillas lecheras. Se realizó un estudio de diseño de bloques completos al azar de 10 semanas utilizando 36 novillas [224 d ± 6 d de edad; 158 kg ± 21 kg de peso corporal (PV)] para evaluar los efectos del tratamiento dietético sobre la ganancia diaria de peso (GDPV) y la salud ruminal. Los tratamientos fueron (1) F: C 70:30 con una consumo de materia seca (CMS) de 4.71 kg / día, (2) F: C 60:40 con 4.76 kg / día de CMS, y (3) F: C 50:50 con un CMS de 4.68 kg / día. Las novillas estuvieron bajo un sistema de alimentación restringida en grupos de seis animales. El pesaje de los animales, las muestras fecales y de alimento se tomaron cada dos semanas. Las raciones se formularon en un programa de alimentación de precisión para proporcionar iguales cantidades de EM (Energía Metabolizable)/ kg de MS (Materia Seca) y proteína cruda (PC)/ kg de MS, para cumplir con las directrices del National Research Council (NRC, 2001). Los animales alimentados con la dieta F: C 60:40 (T2) obtuvieron las GDPV más alta, seguido de los animales alimentados con F: C 70:30 (T1). Sin embargo, no se observaron diferencias (p<0.05) en las GDPV entre los tratamientos durante cada semana de muestreo. Todas las muestras fecales de los tratamientos analizadas con el Nasco Digestion Analyzer retuvieron el mayor porcentaje de partículas en la criba del medio y lograron obtener la retención de partículas esperada para la criba superior, sin embargo, no hubo una diferencia estadística de la distribución de partículas entre los tratamientos.
The objective of this study was to determine the effect of three forage-to-concentrate ratios (F:C) in growing dairy heifers. A 10-wk randomized complete block design study was conducted using 36 heifers [224 d ± 6 d of age; 158 kg ± 21 kg of body weight (BW)] to evaluate effects of dietary treatment on average daily gain (ADG) and ruminal health. Treatments were (1) F:C 70:30 with a dry matter intake (DMI) of 4.71 kg/day, (2) F:C 60:40 with 4.76 kg/day of DMI, and (3) F:C 50:50 with a DMI of 4.68 kg/day. Heifers were limit-fed in groups of six animals. Heifers were weighed, and fecal and feed samples were taken every two weeks. Rations were formulated in a precisionfeeding program to provide equal ME (metabolizable energy)/kg of DM and crude protein (CP)/kg of DM content and to meet guidelines of National Research Council (NRC, 2001). Animals fed F:C 60:40 (T2) diet obtained the highest ADG, followed by animals fed F:C 70:30 (T1). However, no differences were observed (p<0.05) on ADG between treatments during each sample week. All treatments’ fecal samples analyzed by Nasco Digestion Analyzer retained the higher percentage of particles in the middle screen and achieved the expected particle concentration for the top screen, however there was not statistical difference of particle distribution between treatments.
The objective of this study was to determine the effect of three forage-to-concentrate ratios (F:C) in growing dairy heifers. A 10-wk randomized complete block design study was conducted using 36 heifers [224 d ± 6 d of age; 158 kg ± 21 kg of body weight (BW)] to evaluate effects of dietary treatment on average daily gain (ADG) and ruminal health. Treatments were (1) F:C 70:30 with a dry matter intake (DMI) of 4.71 kg/day, (2) F:C 60:40 with 4.76 kg/day of DMI, and (3) F:C 50:50 with a DMI of 4.68 kg/day. Heifers were limit-fed in groups of six animals. Heifers were weighed, and fecal and feed samples were taken every two weeks. Rations were formulated in a precisionfeeding program to provide equal ME (metabolizable energy)/kg of DM and crude protein (CP)/kg of DM content and to meet guidelines of National Research Council (NRC, 2001). Animals fed F:C 60:40 (T2) diet obtained the highest ADG, followed by animals fed F:C 70:30 (T1). However, no differences were observed (p<0.05) on ADG between treatments during each sample week. All treatments’ fecal samples analyzed by Nasco Digestion Analyzer retained the higher percentage of particles in the middle screen and achieved the expected particle concentration for the top screen, however there was not statistical difference of particle distribution between treatments.
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ALIMENTACION DEL GANADO, FORRAJES, PIENSOS CONCENTRADOS, DESARROLLO BIOLOGICO, NOVILLAS, GANADO DE LECHE