Fertilization external

In vitro Describing biological processes that are made to occur outside the living body, in laboratory apparatus (literally in glass , i.e. in a test tube). In in vitro fertilization, mature egg cells are removed from the ovary of a woman unable to conceive normally and fertilized externally the resultant blastocyst is implanted into her uterus. Compare in VIVO. 

In addition to this book, volunteered papers presented at ISMOM2004 and accepted after rigorous external review was published as a special issue by the international journal Biology and Fertility of Soils. This special issue serves a companion volume of this IUSS- and IUPAC-sponsored book published by Springer-Verlag. 

It has been reported that in the UK the external costs of agriculture in 1996 amounted to a staggering 89% of the average net farm income (Pretty et al. 2000), that annual damage by pesticides and fertilizers to water quality is suspected to range in the billions of dollars (Doran et al. 1996) and that annual off-site damages from soil erosion by water in the USA are over US 7 billion (Pimentel et al. 1993). 

Dilly O, Nannipieri P (2001) Organic and mineral fertilization, respectively, increase and decrease the development of external mycelium of arbuscular mycorrhizal fungi in a long-term field experiment. Biol Fert Soils 34 64-72... 

For all the options described above, effects on male and female fertility can be evaluated separately by conducting separate studies in which only one sex is treated. The treatment periods are the same, but the treated animals are cohabited with untreated animals of the opposite sex. In the male fertility study, the untreated females are terminated after the middle of gestation and terminal observations include embryo survival and possibly external examination of fetuses (if terminated at the end of gestation) (Tanimura, 1990). The advantage of conducting separate male and female studies is that, if there are effects, is it clear which sex was affected by treatment. Often when effects are seen in a combined male and female study, additional work is required to resolve which sex was affected. Either a second cohabitation of the treated males with untreated females is added or studies with only one sex treated must then be conducted. 

When K fertilizers are added to soil, some of the K is used by crops but much is adsorbed on external exchange sites in the soil and even more on slowly exchangeable sites. From the discussion above on types of exchange sites, one would expect that these residues of K would absorb on K selective sites, and thus,... 

As with the fertility study only one species is required, and the rat is the most commonly used species. The duration of treatment begins where the fertility study leaves off and continues through the lactation period (i.e., GD 6 to LD 21). The dams are allowed to deliver naturally, and all pups are evaluated at birth for external abnormalities and viability. Pups continue to be housed with their mothers until weaning (LD 21 = PND 21). Most laboratories reduce the number of pups per litter on PND 3 (or 4) and 21 however, it is also acceptable to retain all pups. 

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