Biomaterial Database

[Feed conversion and the energy requirement of pregnant heifers]. 1978

G Burlacu, and G Băla, and A Christian, and V Rus, and J Stavri

Eight Holstein heifers were subjected to experiments running over the entire pregnancy period to investigate the conversion of rations mainly made up of maize silage (85% of the ration's dry matter) by the experimental animals. Both digestible and metabolizable energy (ME) and the energy requirement were studied. The live weight (LW) of the heifers was found to rise linearly during the entire pregnancy period being 422 kg at service and reaching 565 kg at calving. Feed intake, referred to 1 kg live weight0.75, was almost constant until the 7th month of gestation and declined gradually until parturition. The degree of digestibility and metabolizability of the energy contained in the silage-bases rations prove equal over the whole gestation period. The energy required for maintenance and gravidity (y) was found to rise exponentially as pregnancy advance (t). This relationship is reflected by the equation: ME, kcal/kg LW0.75y=135+0.2590.0206t range of significance=+/-0.07 During the last two months of gestation, a negative energy balance was found. This negative energy balance corresponds with a negative fat balance and a reduction, of the respiratory quotient, a fact suggesting to the mobilisation of body fat reserves by the mother to cover the increased energy requirement during pregnancy. The protein balance was found continuously positive during the entire gestation period. The conversion of metabolizable energy for fetus development was found to be 8.13%.

UI	MeSH Term	Description	Entries
D008053	Lipid Mobilization	LIPOLYSIS of stored LIPIDS in the ADIPOSE TISSUE to release FREE FATTY ACIDS. Mobilization of stored lipids is under the regulation of lipolytic signals (CATECHOLAMINES) or anti-lipolytic signals (INSULIN) via their actions on the hormone-sensitive LIPASE. This concept does not include lipid transport.	Lipid Mobilizations,Mobilization, Lipid,Mobilizations, Lipid
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011270	Pregnancy, Animal	The process of bearing developing young (EMBRYOS or FETUSES) in utero in non-human mammals, beginning from FERTILIZATION to BIRTH.	Animal Pregnancies,Animal Pregnancy,Pregnancies, Animal
D001835	Body Weight	The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.	Body Weights,Weight, Body,Weights, Body
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D004734	Energy Metabolism	The chemical reactions involved in the production and utilization of various forms of energy in cells.	Bioenergetics,Energy Expenditure,Bioenergetic,Energy Expenditures,Energy Metabolisms,Expenditure, Energy,Expenditures, Energy,Metabolism, Energy,Metabolisms, Energy
D005260	Female		Females
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, Fetal
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia