Northern elephant seals, Mirounga angustirostris, fast completely from food and water during lactation. Previous investigations of maternal investment suggested physiological constraints on the level of energy expenditure during lactation. In this study, two components of phocid fasting physiology, protein sparing and reduced glomerular filtration rate, were examined for effects of changing bod...

One of the great contributions of Armsby to the science of animal nutrition was the demonstration that the requirements of animals for nutrients, and the values of feeds in covering these requirements, are two separate and distinct problems, requiring different experimental methods for their solution. The requirement of an animal for energy, for example, must involve a study of the heat product...

Phocid seals are one of the few groups of mammals capable of sustaining the energetic demands of lactation entirely through body nutrient stores while fasting. Lactation performance of the female in turn influences the rate and pattern of pup growth. We examined variation in and patterns of milk composition and production, maternal energy output, and pup growth and energy deposition over the en...

The objective of this study was to quantify the genetic association of body energy assessed throughout lactation with a cow's fertility. Nine direct and indirect body energy traits were defined at different stages of lactation. Four were daily records of energy balance, energy content, cumulative effective energy (CEE) and body condition score (BCS) calculated between lactation days 4 and 311. ...

The objectives of this research were to (1) determine the feed intake, digestibility, and energy utilization (2) estimate net value cassava chips consumed by lactating dairy cows. Four multiparous Holstein–Friesian crossbred cows at 139 ± 33 (mean SD) day in milk assigned according a 4 × Latin square design with four periods. treatments included diet substituted on 0%, 12%, 24%, 36% dry matter ...

Adaptivity of eating and rumination behavior are assumed to play a particular role for cows in low-input systems, because they more frequently challenged by altering forage quality. The present study examined relations between quality, chewing efficiency estimates dairy from Swiss zero-concentrate organic farming systems. A total 102 Fleckvieh on two farms were observed during one full producti...