Fertility testing

Common Study Protocols. The dog is the most commonly used nonrodent species in safety assessment testing (i.e., acute, subchronic, and chronic studies). The exception to this is its use in developmental toxicity and reproductive studies. For developmental toxicity studies, the dog does not appear to be as sensitive an indicator of teratogens as other nonrodent species such as the monkey (Earl et al., 1973) or the ferret (Gulamhusein et al., 1980), and, for reproductive studies, the dog is not the species of choice because fertility testing is difficult to conduct (due to prolonged anestrus and the unpredictability of the onset of proestrus) and there is no reliable procedure for induction of estrus or ovulation. 

For information on statutes and guidelines relevant to sexual function and fertility testing, the reader is referred to the references cited in chapter 2. 

Protocol is similar to that of fertility testing using rats and rabbits. 

This test is usually much more sensitive, but considerably more expensive and slower, than the dominant-lethal test,131 and it deals with a clearly defined type of mutation that is transmitted to and scored in viable offspring. Males are exposed to the test substance and mated to untreated females. Male progeny (usually derived only from post-sperroatogonial treatments) are tested for translocations by the fertility test or the cytogenetic test. In the fertility test, males are tested, usually with a sequential procedure, to determine fertility rates.137 Animals suspected of having a translocation (because of decreased fertility) are then subjected to cytologic examination. 

The observations made were 1) the uniformity of the mixture after certain time intervals and 2) the number of inversions required to resuspend the settled material. This gives an indication of the utility of a mixture after being left in a spray tank for an extended period of time. These data are given in Tables III and IV. These data indicate that BALAN Dry Flowable is compatible with the three liquid fertilizers tested and that no compatibility agent is required when BALAN Dry Flowable is used alone. In the case of tank mixes with other herbicides, the compatibility agents sometimes increase the uniformity of the mixture. For an example, see BALAN/Emulsifiable Concentrate D with and without Compatt (Table IV). 

The pnedominsnt form of vitamin E in food is ot-tocopheml. This form of the vitamin is also the most biologicalJy potent form (100 n), as determined by the rat fertility test. Other forms (and their relati e potencies) are l-tocophenol (40%), y-tocophcrol (10%), -tocopherol (1%), and a-tocotricnol (25 n). The rat fertility test is performed as follows. Female rats are fed diets deficient in vitamin E, sufficient in (1-tocopherol, or containing a known amount of the test compound. The rats are then mated with maJe rats. The number of living fetuses in the uterus of the female rat is then used to assess the potency of the test compound, relative to n-toco-pherol. I he deficient state results in dead fetuses, spontaneous abortions, and fetal resorptions,... 

Bovine oocyte fertilization test Formation of female and male pronucleus after penetration of sperm into matured oocytes Hazard identification that could affect fertility... 

Effects on the testis were evaluated in adult male rats that were neonatally exposed to either Aroclor 1242 ( iO, 40, or 80 mg/kg/day) or Aroclor 1254 ( 40 or 40 mg/kg/day) by daily subcutaneous injection from birth to PND 25 (Cooke et al. 1996). Examinations at 135 days of age showed significantly increased testis weight at 40 mg/kg/day Aroclor 1242 and 40 mg/kg/day Aroclor 1254, and increased daily sperm production at 10 mg/kg/day Aroclor 1242 and 40 mg/kg/day Aroclor 1254. Sertoli cell proliferation was also increased in exposed rats (only examined in 15-day-old pups treated with 40 mg/kg/day Aroclor 1242). Both Aroclor 1242 and 1254 also suppressed serum thyroxine (T4) concentrations and T4 replacement decreased or eliminated the testicular effects. As discussed in Section 3.2.2.8 (Endocrine Effects), other studies also indicate that hypothyroidism is involved in PCB-induced testicular effects in neonatal rats. Fertility tests showed that all Aroclor 1242-treated rats successfully impregnated unexposed females (Aroclor 1254 was not tested). 

USE Mainly in the protection of foods for the removal of glucose from egg albumin and whole eggs prior to drying. To remove oxygen from canned foods, soft drinks, beer, and stored food. In the manuf ol test papers for diabetes control and fertility tests. To stabilize ascorbic acid and vitamin B,-prepns. In combination with catalase, for treatment of food wrappers to prevent oxidative deterioration of food Sarett, Scott, U.S. pat. 2,765,233 (1956 to Ban L. Sarett). 

With the increased availability of a variety of home diagnostic tests, the sale of home pregnancy, ovulation, and fertility tests alone was a 330 million dollar business in 2005. Home pregnancy tests have been utilized since 1976, with approximately 26 devices currently available in the United States. These tests claim that they can be utilized on the first day of a missed menstrual period (or, for oertain devioes, even earlier) with more than 99% diagnostic accuracy for pregnancy. Despite these claims, accurate results are obtained only a fraction of the time (Table 46.1) (1). 

Chronic toxicity Long term orai toxicity and Fertility test for Daphnia magna Effects on algal growth... 

Mutagenic effects claimed on basis of fertility tests done... 

Hydrogen cyanide ferromagnetic fluid, separation Ferric lignosulfonate ferroniobium, alloy steels Niobium fertility test mfg. 

The role of the extension service on farm-level use cannot be overestimated because it educates farmers on fertilizer quality and also promotes proper fertilizer use. In some countries the extension service carries out fertilizer tests to show the farmer the benefits and the costs of using fertilizer. The farmer pays for fertilizers only in cases when positive results and promised yields have been achieved. Therefore, it is important that the... 

Although there is no substitute for accurate measurements, it is unlikely that experiments will provide rate constants for all the reactions that may be important in chemical models of interstellar clouds. Already, however, the measured values provide a fertile testing ground for theories of the lands propounded by Clary [10] and Troe [6]. Until such time as either experiment or detailed theory provides a reliable kinetic data base, modellers are likely to appreciate guidelines as to how they might estimate approximate rate constants for neutral-neutral reactions between 10 and 50 K, since it is now clear that the rate of any neutral-neutral reaction which has a rate constant within an order of magnitude of the collisional value at room temperature may have a rate constant which is determined by capture [21] and which may increase as the temperature is lowered. 

---