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• 1. [Article] Some effects of diethylstilbestrol on sexual maturation and growth of male calves

  Six experiments were conducted to determine the effects of DES implantation on preweaning performance and sexual maturation of male calves when implanted at various stages of development and different ...

  Citation × Citation Citation Abstract Copy Title: Some effects of diethylstilbestrol on sexual maturation and growth of male calves Author: Patton, Westley R. Six experiments were conducted to determine the effects of DES implantation on preweaning performance and sexual maturation of male calves when implanted at various stages of development and different sites. Calves receiving DES implants in Experiments I and II were implanted at birth, at birth and at about three months of age, or at about three months of age. Some of the calves in Experiment I were left intact until slaughter, while the remainder of the calves in the first two trials were castrated two weeks prior to weaning. Statistical analysis of data from the first trial showed that calves implanted (12 mg.) at birth gained significantly (P < .05) faster to three months of age than did non-implanted calves and held a slight advantage to weaning. An advantage in preweaning performance was not observed for implanted calves in Experiment II. However, there was a significant (P < .01) reduction in the average external diameter of seminiferous tubules in calves receiving two preweaning implants. In both trials, DES treatment caused a delay in development of secondary sex characteristics, such as crest, increased shoulder development and curly hair about the head. In Experiment IIIa there were no differences in preweaning performance and sexual maturation between bull calves implanted at birth and at three months of age and those implanted at three months of age. In yearling bulls with the same treatments (Experiment IIIb) there was a delay in the onset of semen production. Bull calves in Experiment IV received implants at birth, at three months of age, at weaning and after 110 days in the feedlot; the same treatment without the birth implant; or no DES implants. There was a trend toward increased average daily gain with increasing levels of DES. The testes weight was significantly (P < .01) decreased by DES treatment. Furthermore, testes weights of the two DES treatments were significantly (P < .05) different. There was a significant (P < .01) reduction in average external seminiferous tubule diameter with each increase in DES level. Two levels of scrotal DES implants at birth plus ear implants at three months of age were compared to two levels of ear implants at birth plus ear implants at three months of age. In this experiment (Experiment V) scrotal implants did not cause an increase in gain to three months, but there was an advantage over the controls to weaning. Gains were similar for scrotal and ear implants to weaning. At weaning there was a significant (P < .01) reduction in testes weight and average external seminiferous tubule diameter with DES treatment. Experiment VI dealt with bull and steer calves implanted with DES at three different stages of development prior to weaning. At slaughter the inside diameters of the urethras were measured at four locations. Urethra diameter was significantly (P < .01) reduced by castration. DES implants caused a significant (P < .01) increase in the inside diameter of the urethras of steers, but had no effect in bulls. Title: Some effects of diethylstilbestrol on sexual maturation and growth of male calves Author: Patton, Westley R. Six experiments were conducted to determine the effects of DES implantation on preweaning performance and sexual maturation of male calves when implanted at various stages of development and different sites. Calves receiving DES implants in Experiments I and II were implanted at birth, at birth and at about three months of age, or at about three months of age. Some of the calves in Experiment I were left intact until slaughter, while the remainder of the calves in the first two trials were castrated two weeks prior to weaning. Statistical analysis of data from the first trial showed that calves implanted (12 mg.) at birth gained significantly (P < .05) faster to three months of age than did non-implanted calves and held a slight advantage to weaning. An advantage in preweaning performance was not observed for implanted calves in Experiment II. However, there was a significant (P < .01) reduction in the average external diameter of seminiferous tubules in calves receiving two preweaning implants. In both trials, DES treatment caused a delay in development of secondary sex characteristics, such as crest, increased shoulder development and curly hair about the head. In Experiment IIIa there were no differences in preweaning performance and sexual maturation between bull calves implanted at birth and at three months of age and those implanted at three months of age. In yearling bulls with the same treatments (Experiment IIIb) there was a delay in the onset of semen production. Bull calves in Experiment IV received implants at birth, at three months of age, at weaning and after 110 days in the feedlot; the same treatment without the birth implant; or no DES implants. There was a trend toward increased average daily gain with increasing levels of DES. The testes weight was significantly (P < .01) decreased by DES treatment. Furthermore, testes weights of the two DES treatments were significantly (P < .05) different. There was a significant (P < .01) reduction in average external seminiferous tubule diameter with each increase in DES level. Two levels of scrotal DES implants at birth plus ear implants at three months of age were compared to two levels of ear implants at birth plus ear implants at three months of age. In this experiment (Experiment V) scrotal implants did not cause an increase in gain to three months, but there was an advantage over the controls to weaning. Gains were similar for scrotal and ear implants to weaning. At weaning there was a significant (P < .01) reduction in testes weight and average external seminiferous tubule diameter with DES treatment. Experiment VI dealt with bull and steer calves implanted with DES at three different stages of development prior to weaning. At slaughter the inside diameters of the urethras were measured at four locations. Urethra diameter was significantly (P < .01) reduced by castration. DES implants caused a significant (P < .01) increase in the inside diameter of the urethras of steers, but had no effect in bulls. Close

• 2. [Image] RA_PETR_TG_0885

  	Small surface with several deeply pecked images: two bulls, two horses attached to the pole of a faint (unfinished?) cart, and two other horses. On boulder on terrace above right bank of the upper Tsagaan ...
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0885 Year: 2004 Small surface with several deeply pecked images: two bulls, two horses attached to the pole of a faint (unfinished?) cart, and two other horses. On boulder on terrace above right bank of the upper Tsagaan Gol.; Bronze Age Title: RA_PETR_TG_0885 Year: 2004 Small surface with several deeply pecked images: two bulls, two horses attached to the pole of a faint (unfinished?) cart, and two other horses. On boulder on terrace above right bank of the upper Tsagaan Gol.; Bronze Age Close

• 3. [Image] RA_PETR_TG_0593

  	Detail of vehicle with large spoked wheels (unfinished). Horses stationary; large bull on right may be executed at a later date.; Bronze Age
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0593 Year: 2000 Detail of vehicle with large spoked wheels (unfinished). Horses stationary; large bull on right may be executed at a later date.; Bronze Age Title: RA_PETR_TG_0593 Year: 2000 Detail of vehicle with large spoked wheels (unfinished). Horses stationary; large bull on right may be executed at a later date.; Bronze Age Close

• 4. [Image] RA_PETR_TG_0926

  	Section of ""Large Panel"" with two fine bulls partially hidden by lichen, fine horse from same period and hand; and an obscurely visible cart in upper left, seen in flare.; Bronze Age
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0926 Year: 2004 Section of ""Large Panel"" with two fine bulls partially hidden by lichen, fine horse from same period and hand; and an obscurely visible cart in upper left, seen in flare.; Bronze Age Title: RA_PETR_TG_0926 Year: 2004 Section of ""Large Panel"" with two fine bulls partially hidden by lichen, fine horse from same period and hand; and an obscurely visible cart in upper left, seen in flare.; Bronze Age Close

• 5. [Image] RA_PETR_TG_0925

  	Section of ""Large Panel"" with two fine bulls partially hidden by lichen, fine horse from same period and hand; and an obscurely visible cart in upper left.; Bronze Age
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0925 Year: 2004 Section of ""Large Panel"" with two fine bulls partially hidden by lichen, fine horse from same period and hand; and an obscurely visible cart in upper left.; Bronze Age Title: RA_PETR_TG_0925 Year: 2004 Section of ""Large Panel"" with two fine bulls partially hidden by lichen, fine horse from same period and hand; and an obscurely visible cart in upper left.; Bronze Age Close

• 6. [Image] RA_PETR_TG_0739

  	Several large yaks on top of a high, rough surfaced outcrop overlooking lower valley.; Late Bronze Age
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0739 Year: 1996 Several large yaks on top of a high, rough surfaced outcrop overlooking lower valley.; Late Bronze Age Title: RA_PETR_TG_0739 Year: 1996 Several large yaks on top of a high, rough surfaced outcrop overlooking lower valley.; Late Bronze Age Close

• 7. [Image] RA_PETR_TG_0260

  	Detail of spotted bull with long horns from upper section of ""Second Bull Panel"". Possible unfinished long bow below bull's head.; Bronze Age
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0260 Year: 2001 Detail of spotted bull with long horns from upper section of ""Second Bull Panel"". Possible unfinished long bow below bull's head.; Bronze Age Title: RA_PETR_TG_0260 Year: 2001 Detail of spotted bull with long horns from upper section of ""Second Bull Panel"". Possible unfinished long bow below bull's head.; Bronze Age Close

• 8. [Image] RA_PETR_TG_0308

  	Detail of large panel with main scene: woman leading two huge bulls; the tail of the lower bull has been pecked over a large animals (cow?). On upper left is visible the rectangular dwelling.; Bronze A...
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0308 Year: 2001 Detail of large panel with main scene: woman leading two huge bulls; the tail of the lower bull has been pecked over a large animals (cow?). On upper left is visible the rectangular dwelling.; Bronze Age Title: RA_PETR_TG_0308 Year: 2001 Detail of large panel with main scene: woman leading two huge bulls; the tail of the lower bull has been pecked over a large animals (cow?). On upper left is visible the rectangular dwelling.; Bronze Age Close

• 9. [Image] RA_PETR_TG_0405

  	Two bulls in confronting positions to form a circular image.; Late Bronze Age; Iron Age; Uncertain
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0405 Year: 2001 Two bulls in confronting positions to form a circular image.; Late Bronze Age; Iron Age; Uncertain Title: RA_PETR_TG_0405 Year: 2001 Two bulls in confronting positions to form a circular image.; Late Bronze Age; Iron Age; Uncertain Close

• 10. [Image] RA_PETR_TG_0452

  	Two men apparently swinging around the heads of two confronting bulls. The leg of the bull on the left overlays an earlier, scored image. Modern mark on upper left.; Bronze Age; Late Bronze Age; modern ...
  	Citation × Citation Citation Abstract Copy Title: RA_PETR_TG_0452 Year: 2000 Two men apparently swinging around the heads of two confronting bulls. The leg of the bull on the left overlays an earlier, scored image. Modern mark on upper left.; Bronze Age; Late Bronze Age; modern (generic time frame) Title: RA_PETR_TG_0452 Year: 2000 Two men apparently swinging around the heads of two confronting bulls. The leg of the bull on the left overlays an earlier, scored image. Modern mark on upper left.; Bronze Age; Late Bronze Age; modern (generic time frame) Close