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W Waddell

Publications and source records attributed to W Waddell.

6 recordsLinked to original sources
PubMed1998

Semen parameters and electron microscope observations of spermatozoa of the red wolf, Canis rufus.

Semen parameters were evaluated on ejaculates of a captive population of red wolves (Canis rufus) sampled over two consecutive mating seasons. A total of 31 samples from 15 animals yielded mean sperm motility of 69.6 +/- 19.4%, mean sperm density of 131 +/- 124 x 10(6) ml-1, mean total number of spermatozoa of 470 +/- 465 x 10(6) and mean percentage morphologically abnormal spermatozoa of 35 +/- 11.8%. Restricting the data to animals sampled three times or more or limiting the samples to proven breeders resulted in statistically non-significant differences in these numbers (P < 0.05). When compared with data from other canines the seminal parameters of red wolves are at the lower extremes of the range. In particular the proportion of morphologically abnormal spermatozoa (35%) is approximately twice that seen in other canine species. Light microscopic analysis of abnormal forms revealed that almost half (45%) were bent defects, another 40% were secondary defects (coiled, detached and immature) and 15% were primary defects. Electron microscopy confirmed the presence of substantial numbers of morphologically abnormal forms including double-headed and double-flagellar cells, bent or kinked forms especially in the neck region, acrosomal abnormalities and bizarre spermatids. Approximately one-third of the samples also showed the presence of white blood cells, in some cases demonstrating sperm phagocytosis (spermophagy). These results are consistent with the concept of declining sperm parameters associated with restricted gene pools in numerically limited populations. However, alternative explanations are also explored.

Animals↗
PubMed1994

Spermophagy in semen in the red wolf, Canis rufus.

The red wolf (Canis rufus) is an endangered species with 194 individuals remaining in the wild and in various captive facilities. Breeding efforts at the Graham, WA site (Point Defiance Zoo and Aquarium) have involved artificial insemination with fresh or frozen semen in an effort to increase population and maximize the genetic potential of the stock. Electron microscopic observations were made in semen specimens obtained by electro-ejaculation from mature males prior to their use in an effort to determine semen parameters that might be useful in guiding breeding procedures. Sperm samples were either fixed immediately or treated with capacitating media and fixed after 4 to 7 hr of incubation. Many of the specimens examined were pyospermic (white cell in semen) and showed evidence of spermophagy, primarily by neutrophils. Of the six animals surveyed, only one showed little evidence of spermophagy, and three had extensive pyospermia and spermophagy but this finding was not correlated with fertility. Samples fixed immediately as well as those incubated for several hours showed evidence of spermophagy, indicating that the phagocytosis was not the result of culture. Gene pool restriction and/or captive stress may be contributing factors of reduced semen quality.

Animals↗
PubMed1989

Worker exposure to lead titanate zirconate in an Ontario company.

An Ontario plant with 101 workers, producing and using the ceramic compound lead titanate zirconate (LTZ), was investigated. Although air lead levels were high in most plant areas, 82 workers not exposed to lead oxide but to LTZ in the process had normal blood lead levels. In addition, no radiographic changes or abnormal pulmonary function test results were detected in 61 examined workers. The particle size of LTZ was determined to be less than 5 micrometers, and the solubility of LTZ in body fluids was found to be significantly less than lead oxide. The authors postulate that the observed low toxicity of LTZ could be due to its low solubility in body fluids. Further studies of the toxicity of LTZ and other less soluble lead compounds are recommended.

Air Pollutants, Occupational↗