concentrate (FS); and 3) a diet containing 200 g/d of
microencapsulated fish oil in addition to CT diet (FO).
Formulation and chemical composition of the diets are
shown in Table 1. Cows were housed in tie stalls and
water was available ad libitum. The diets were fed twice
daily and each group of cows was fed separately. Cows
in all groups completely consumed the daily ration
given. The DMI was 16.57 kg/d for CT cows, 16.75
kg/d for FO cows, and 16.61 kg/d for FS cows (SE ±
0.2 kg/d). The NEL of the diet was calculated by using
NRC (2001) (Table1). Milking was carried out twice
daily (0600 and 1700 h) and milk yield was recorded
every 14 d. Environment temperature and humidity
on the farm were monitored using TIG2-TH thermohygrographs
(LSI, Settala Premenugo–Milan, Italy).
The temperature-humidity index (THI) was calculated
as proposed by Kelly and Bond (1971).