Blood samples were obtained sequentially from 10 dairy cows around the time of parturition to assess plasma fluctuations in estradiol-17β (E2) levels in association with those of several bone resorption markers. Plasma E2 concentration increased sharply a few days prepartum and decreased quickly after parturition. In terms of bone resorption markers, the plasma level of tartrate-resistant acid ...

Physical and chemical characteristics of dietary ingredients and their interactions can have a large effect on dry matter intake (DMI) of lactating cows. Physical limitations caused by distension of the reticulo-rumen or other compartments of the gastrointestinal tract often limit DMI of high producing cows or cows fed high forage diets. Fermentation acids also limit DMI from a combination of i...

Thirty-two Afshari lambs were used in a completely randomized design with a 2 × 2 factorial arrangement of treatments to evaluate a nutritional supplement designed to provide multiple gluconeogenic precursors during heat stress (HS). Lambs were housed in thermal neutral (TN) conditions and fed ad libitum for 8 d to obtain covariate data (period 1 [P1]) for the subsequent experimental period (pe...

To examine the effect of including oil in diets on early lactating productive performance parameters including; dry matter intake, milk production and components, body condition score, body weight and negative energy balance; twenty multiparous Holstein cows were randomly assigned to the experimental diets from 21 days before predicted calving time to 50 days in milk. Treatments including 1) co...

Sixty Holstein cows were assigned to two treatments at 21 d before calving and were group-fed a prepartum diet with or without yeast culture. After parturition, cows were individually fed one of five treatments for 140 d: 1) 21% forage neutral detergent fiber (NDF) without yeast culture, 2) 21% forage NDF with yeast culture, 3) 17% forage NDF without yeast culture, 4) 17% forage NDF with yeast ...

This study investigated the effects of an amylase-enabled corn silage on lactational performance, enteric CH4 emission, and rumen fermentation lactating dairy cows. Following a 2-wk covariate period, 48 Holstein cows were blocked based parity, days in milk, milk yield (MY), emission. Cows randomly assigned to 1 2 treatments 8-wk randomized complete block design experiment: (1) control (CON) fro...

The use of negatively balanced cation-anion rations during the late dry or prepartum period requires excellent monitoring and management. The cows must be separated from the remaining herd and fed a total mixed ration as a group. Lower plasma calcium (Ca) will stimulate the Parathyroid hormone (PTH) and 1-hydroxylase system to increase intestinal absorption of Ca and bone resorption –reduce inc...

thirty two multiparous holstein cows were used in a randomized block design to investigate the effects of feeding diets included two different source of nonfiber carbohydrate during the transition period on dry matter intake (dmi), lactational performance, blood metabolites and parturitional characteristics. cows received total mixed rations containing either macaroni wastes(mw) or steam-flaked...

We evaluated the effects of frequency of energy supplementation on growth and measurements of innate and humoral immune responses of preconditioning beef steers following vaccination. Angus steers ( = 24; 221 ± 6.3 kg; 177 ± 4 d of age) were weaned on d -7 and kept in a single drylot pen with free access to tall fescue hay and concentrate DMI at 0.5% of BW (50:50 mix of soyhulls and corn gluten...

Ten male Merghoz goats with initial live weights of 29.2 ± 1.2 kg (Mean±SE) were used to investigate the effect of natural changes in photoperiod on dry matter intake (DMI) and reproductive activity during a 365 day study. The bucks were housed in individual pens, under natural daylength condition at west of Iran, Kermanshah (34˚ 18¢N and 47˚ 3¢E and 1420 m above sea level). A diet was offered ...