Functions weaning

The mmen is not functional at birth and milk is shunted to the abomasum. One to two weeks after birth, the neonate consumes soHd food if offered. A calf or lamb that is nursing tends to nibble the mother s feed. An alternative method of raising the neonate is to remove it from its mother at a very young age, <1 week. A common example of an early weaning situation is the dairy calf that is removed from the cow soon after birth so that the cow s milk supply might be devoted entirely to production. In this instance, the neonate requires complete dietary supplementation with milk replacer. Sources of milk replacer protein have traditionally included milk protein but may also include soybean proteins, fish protein concentrates, field bean proteins, pea protein concentrates, and yeast protein (4). Information on the digestibiUty of some of these protein sources is available (4). 

Genetic disruption of dopamine synthesis in mice lacking TH shows that dopamine is not essential for development. However, dopamine deficient mice do not survive long after weaning unless treated with l-DOPA. These mice display severe aphagia and adipsia and loss of motor function. While these mice have a major reduction in dopamine levels some residual dopamine can be detected that is generated through the action of tyrosinases. 

Finally, growth after weaning is no longer limited by the mother but by other environmental factors many of which are now integrated by functions in the CNS, and growth of the organism is thus largely controlled centrally. 

Castillo, M., Martin-Orue, S. M., Taylor-Pickard, J. A., Perez, J. F., and Gasa, J. (2008). Use of mannanoligosaccharides and zinc chelate as growth promoters and diarrhea preventative in weaning pigs Effects on microbiota and gut function. /. Anim. Sci. 86, 94-101. 

At high dose levels to the dam many suckling pups died before weaning, the viability index being zero for the generation. Hence dietary HCB decreased the number of pups that survived to weaning. A minimum, e.g., no effect, dose level of 20 ppm of HCB was established (refs. 95a,b,c). As with other chloroorganics, HCB affects the CNS and with it a variety of essential vital functions. 

Physical dependence Physical dependence occurs when a person s body becomes accustomed to a certain medication and cannot function properly without it. Only certain medications can cause physical dependence. Individuals who are physically dependent on a medication cannot discontinue that drug suddenly, but instead must be slowly weaned off of the medication. If the medication is stopped abruptly, patients will experience physical symptoms of withdrawal and may become very ill. 

Saavedra, J.M., Tschernia, A., Moore, N., Abi-Hanna, A., Coletta, F., Emenhiser, C., and Yolken, R., Gastrointestinal function in infants consuming a weaning food supplemented with oligofructose — a prebiotic, J. Pediatr. Gastroenterol. Nutr., 29, A95, 1999. 

Birth to weaning (adult female reproductive functions, parturition, lactation, neonate adaptation to extrauterine life, preweaning development and growth)... 

Weaning to sexual maturity (postweaning development and growth, maturation, adaptation to independent life, attainment to full sexual function). 

Designing sustainable produaion systems based upon an understanding of ecosystem function will be the easy part. Weaning the economy from its focus on short-term profits and from its dependence upon an unsustainable source of petroleum will be the hard part. 

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