Energy Balance Data from Lactating Dairy Goats Offered Total Mixed Diets

Abstract

The objective of the study was to develop a univariate model for analyzing energy balance data from lactating goats at mid lactation and determine maintenance requirements and partial efficiencies of energy utilization. Energy balance data from eight studies involving lactating Murciano-Granadina goats fed total mixed diets, which accounted for a variation in metabolizable energy (MEI) intake, milk energy output (EI), and tissue energy balance, were used. The database included records obtained by indirect calorimetry. Data were adjusted with a mixed model that included the study as a random effect. Then, two multivariate linear models were obtained: metabolizable and net energy models. The metabolizable model was 1 β , 2 β and 3 β were the parameters, Tg was tissue energy retention and Tl the milk energy derived from body stores. For a better fitted proposed model, net energy for maintenance (NEm) was 283 kJ/kg of Body Weight 0.75 (BW) per day, and the efficiency of utilization of ME for lactation (k l), body weight gain (k g) and body tissue mobilization for milk production (k t) were 62%, 83% and 78%, respectively. Maintenance requirements and partial efficiencies for milk production and tissue energy mobilization were similar to the values proposed by INRA (2018). The increase in the efficiency of utilizing dietary energy for gain, compared with other feeding systems, was partially attributed to the stage of lactation, due to that goats were feeding at mid lactation.

Alterations in Energy Partitioning and Methane Emissions in Murciano-Granadina Goats Fed Orange Leaves and Rice Straw as a Replacement for Beet Pulp and Barley Straw

“…Prieto et al [ 40 ] working with adult and castrated male goats attained a value of 443 kJ MEm/kg BW 0.75 per day, and Aguilera et al [ 41 ] obtained 401 kJ/kg BW 0.75 per day. The model obtained by Fernández [ 42 ] had values of 460 kJ MEm/kg BW 0.75 per day. Averaging the studies mentioned above, the MEm would be 445 kJ/kg BW 0.75 per day.…”

Effect of short time precise dietary energy–protein in reproductive parameters of local crossbred dairy goats

“…The National Research Council (NRC) has well-established nutritional criteria for dairy goats [ 1 ]. This feeding approach had no practical or technological limitations [ 2 ]. The consequences of nutritional imbalance on the productive function of ruminants have been extensively studied and evaluated; however, few studies have been conducted on ruminants, especially regarding excessive feed rations.…”