Abstract

Forty Holstein Friesian dairy cows were used to compare alfalfa (ALF) and peanut hay-base (PNT) total mixed rations on performance in periparturient period. Twenty cows were fed ALF diet (16.5% crude protein) and 20 cows were fed PNT diet (19% crude protein). All cows were routinely drenched once daily with propylene glycol as early as 1 week prior to anticipated calving date, until 7 days after calving. Blood samples were collected at -2, 1, 2, 3 and 4 weeks from parturition. Milk yields were recorded daily and milk samples were collected twice a week to determine urea nitrogen concentrations and milk composition. During the 4 weeks postpartum, daily dry matter intake of cows did not differ between the two groups. Serum glucose, non-esterified fatty acid, b-hydroxybutyrate and urea nitrogen concentrations did not differ between the two groups at any sampling times. After calving, decreased glucose and increased nonesterified fatty acid andb-hydroxybutyrate concentrations in the blood indicated that cows in both groups went into negative energy balance status. Serum urea nitrogen concentrations did not change during the sampling period. Cows fed PNT diet seemed to have higher urea nitrogen concentrations in the milk than cows fed ALF diet. Average milk production during the 30 days postpartum was greater for cows fed ALF diet than those fed PNT diet. Milk composition did not differ between groups. Although, average days from calving to first service did not differ between groups, cows fed ALF diet had better conception rate at first service than cows fed PNT diet. In conclusion, cows fed ALF diet could improve milk yield and conception rate. However, in Thailand, replacing PNT with ALF hay in total mixed ration would depend on the economic analysis because ALF hay was exported from a foreign country.

Key words: Alfalfa hay, dairy cow, peanut hay, performance.