Ruminant production contributes to emissions of nitrogen (N) to the environment, principally ammonia (NH3), nitrous oxide (N2O) and di-nitrogen (N2) to air, nitrate (NO3 -) to groundwater and particulate N to surface waters. Variation in dietary N intake will particularly affect excretion of urinary N, which is much more vulnerable to losses than is faecal N. Our objective is to review dietary ...

Milk-fed heavy calves utilize dietary protein with a low efficiency and often develop hyperglycemia and insulin resistance. Distributing the daily nutrient intake over an increasing number of meals increases protein deposition and improves glucose homeostasis. Therefore, we examined effects of feeding frequency (FF) and feeding level (FL) on the diurnal pattern of substrate oxidation and on the...

To detect urea content in milk powder, a nonlinear chemical fingerprint technique was developed. In our study, Belousov-Zhabotinsky oscillatory chemical reaction (B-Z) was performed using milk powder and malonic acid as main dissipative substances. The same dosage of milk powder with or without artificially added urea was introduced to “H+ + Ce4+ + 3 BrO − + malonic acid” oscillating system, re...

four-handed fifty lactating holstein cows with mean body weight of, 597± 40 and 50±20 and days in milk body condi from sure of 3.1±0.4 were blocked by parity and randomly assigned to 3 treatments. each treatment had 3 pens and each pen had 50 cows. the experiment lasted for 60 days (10 days adaptation and 50 days collection period). concentrate to forage ratio was 60 to 40 and alfalfa hay repla...

This study compared the effects of two levels of crude protein (CP) supplementation during a close-up dry period on the productive performance, nitrogen balance, and blood profiles of Holstein cows. Eighteen cows (8 primigravid and 10 multiparous), 21 days prior to calving, were divided into four groups and fed a diet containing a low (11.5 to 12.7% CP) or high (14.1 to 15.3% CP) level of prote...

Milk urea nitrogen (MUN) has been introduced as a means to estimate urinary nitrogen (N) excretion and protein status of dairy cattle. For Holstein cows, the amount of urinary N excreted (g/d) was originally reported to be 12.54 x MUN (mg/dl), but recently urinary N (g/d) was reported to equal 17.64 x MUN (mg/dl). The objectives of the present study were to evaluate models to predict urinary N ...

The absorption of fat and the absorption and retention of nitrogen were studied in 20 children with kwashiorkor. 13 of the 20 had lactose malabsorption and severe diarrhoea on milk feeds. Fat absorption was not affected by lactose-induced diarrhoea, but nitrogen absorption was impaired. Despite this, nitrogen retention was unaffected and it is concluded that milk and milk products would continu...