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C H Rahe

Publications and source records attributed to C H Rahe.

25 records · Page 2Linked to original sources
PubMed1985

The effect of pen density during rearing on subsequent reproductive performance in gilts.

A study involving 109 crossbred gilts of Duroc and Landrace breeding that were reared in equal-sized pens with 8 or 16 pigs/pen was initiated to determine the effects of pen density during rearing on subsequent reproductive and maternal performance. Gilts in pens of eight were allowed 1.06 m2/animal from 30 to 65 kg and 1.25 m2/animal from 65 to 100 kg, whereas those in pens of 16 were allowed only one-half as much floor area per animal. Gilts raised in groups of eight farrowed 1.0 more pigs/litter (P less than .05), and .7 more pigs/litter born alive (P = .15), than gilts reared in groups of 16 pigs/pen. There were no pen-density differences in the number of corpora lutea at 30 d of gestation (P = .33) or in litter birth weight (P = .26). After adjusting by covariance for the number of live pigs at the beginning of the lactation period, gilts from the pen density of 16 had more pigs per litter alive (P less than .01) and heavier litter weights (P less than .05) at 21 d postpartum and higher piglet survival rates to 21 d (P less than .02) than gilts that were reared in the low pen-density of eight pigs/pen. Results of this study indicate that pen density during the growing-finishing period may affect subsequent reproductive and maternal performance of gilts.

Animals↗
PubMed1982

Characterization of [3H] corticosterone binding activity in adrenal incubation media.

Glucocorticoid-binding activity in adrenal incubation media was investigated with regard to characterization of a protein-like ligand. Scatchard analysis of corticosterone binding activity indicated the presence of a single non-interacting protein with a dissociation constant (Kd) of 8.81 X 10(-10) M (0 degrees C), a value which is different from that of plasma and cytoplasmic glucocorticoid binding proteins. In addition, an observed lack of affinity of the protein for dexamethasone distinguishes the protein from Type II cytoplasmic receptor proteins. Thus our data suggest a glucocorticoid-binding protein which is distinct from the two known groups of glucocorticoid-binding proteins, corticosteroid-binding globulin (CBG) and cytoplasmic receptors.

Adrenal Glands↗
PubMed1982

Evidence for an inherent rhythm in pulsatile LH release in ovariectomized cows.

Luteinizing hormone levels were measured in blood samples collected at 5 minute (min) intervals for 3 hours (hr) during the a.m. and p.m. of 3 consecutive days from long-term ovariectomized cows. Levels of LH fluctuated in a pulsatile manner in all animals. During the pulses, LH levels increased rapidly (2.5 to 6.0 ng/ml). Following the rapid increase, a more gradual exponential decline was observed. The interval between pulses was consistent both within and between days of blood sample collection within cows. From the results we suggest that each cow may have an inherent consistent rhythmic pattern of LH release in the absence of an ovarian source of hormones.

Journal Article↗
PubMed1980

Time-dependent loss of radioimmunoassayable levels of progesterone following ambient temperature incubation of heparinized bovine blood.

Plasma progesterone levels in heparinized blood collected at 10 min intervals for 8 continuous hours from four nulliparous Holstein cows on day 3 (early luteal), day 10 or 11 (mid-luteal) and day 18 or 19 of the estrous cycle were found to decline over time when blood was incubated at ambient temperature. The loss was more obvious during the mid-luteal collection period than either the day 3 or day 18 or 19 periods in all cows. This appeared to be associated more with high progesterone levels on day 10 or 11 rather than with differences in the period of the estrous cycle. There was an average decrease in progesterone levels of 3.4, 1.0 and 1.5 ng/ml between samples having the shortest and longest incubation periods on day 10 or 11, day 3 and day 18 or 19, respectively. This apparent decrease in levels of progesterone from bovine blood indicates need in the future for careful consideration concerning the handling of bovine blood collected for subsequent radioimmunoassay (RIA) of progesterone. Further work to elucidate the mechanism which is responsible for the apparent loss is also warranted.

Journal Article↗
PubMed1980

Pattern of plasma luteinizing hormone in the cyclic cow: dependence upon the period of the cycle.

Docile cows were used to characterize the pattern of plasma LH in systemic circulation during three periods [day 3 (early luteal), day 10 or 11 (midluteal) and day 18-19] of the estrous cycle. Blood samples were collected at 10-min intervals for 24 continuous h during each period. Concentration of LH, as measured by RIA, was analyzed by time domain and frequency domain methods of time series analysis. During all periods of the cycle studied, LH fluctuated in a pulsatile manner. During the early luteal period, pulses were classified as low amplitude (delta LH, 0.3-1.8 ng) and high frequency (20-30 pulses/24 h), with each cow exhibiting an inherent rhythmic pattern. However, during the midluteal period, pulses were classified as high amplitude (delta LH, 1.2-7.0 ng) and low frequency (6-8 pulses/24 h), without an inherent rhythmic pattern. Even though patterns differed between the early and midluteal periods in all cows, mean LH concentrations were different (P less than 0.05) in only one cow. On day 18 or 19, two cows exhibited a preovulatory surge of LH. Throughout the surge, LH fluctuated in a pulsatile manner, with a frequency more like the early luteal than the midluteal period. Amplitude of the pulses was greater during the ascending than during the descending portion of the surge. These results suggest that LH fluctuates in a pulsatile manner in the plasma of the cyclic cow, and that the pattern is dependent upon the period of the estrous cycle and is probably modulated by ovarian steroids.

Animals↗
PubMedDate not supplied

Luteinizing hormone releasing hormone, estrogen, and progesterone receptors in canine mammary lesions and tumor cell lines.

Nineteen canine mammary lesions were analyzed for estrogen receptor (ER), progesterone receptor (PR) and luteinizing hormone releasing hormone receptor (LHRHR) content. In addition, nine previously established canine mammary tumor cell lines with known ER and PR were analyzed for LHRHR. The incidence of receptors in the mammary tumor lesions was 21% for LHRHR, 10% for ER and 30% for PR. Statistical correlation was not observed between receptor status and diagnosis of malignant, benign, or hyperplastic lesions. A relationship between LHRHR and ER and PR content of canine mammary lesions or cell lines was not evident. The presence of functional hormone receptors offers opportunity for hormonal treatment of mammary cancer which may not be completely treatable by surgery. The observation of LHRHR in canine mammary tumors may offer therapeutic interventions other than surgery for mammary tumors unresponsive to antiestrogens.

Animals↗