Effects of lasalocid and intermittent feeding of chlortetracycline on the growth of prepubertal dairy heifers.

Forty Holstein heifers entered the 12-wk study at approximately 12 wk of age. At enrollment, heifers were blocked by birth date and assigned to 1 of 4 treatments: (1) carrier (30 g; control); (2) lasalocid + carrier (1 mg/kg of body weight; L); (3) chlortetracycline + carrier (22 mg/kg of body weight; CTC); (4) L + CTC + carrier (CTCL). Heifers on CTC and CTCL were provided treatment Monday through Friday and carrier only on Saturday and Sunday. These heifers were provided their respective treatment during wk 1 to 4, 6, and 10; wk 5, 7 to 9, and 11 to 12 heifers were provided the nonmedicated carrier. Heifers were individually fed a total mixed ration with treatments top-dressed at 1200 h daily. Dry matter intake was monitored for each heifer and feed provided was adjusted according to individual intakes. Skeletal measurements were taken weekly and blood samples were obtained every Monday, Wednesday, and Friday. Blood samples were analyzed for thyroxine concentration via radial immunoassay. Heifers supplemented with L had lower average daily gain , overall body weight gain, and trends for lower daily body length gain and overall girth gain compared with CTC heifers, but similar to control and CTCL heifers. Heifers fed L had lower hip height gain and overall hip height gain compared with CTCL heifers, but similar to control and CTC heifers. Heifers fed L had lower overall withers height gain compared with control heifers, but similar to CTC and CTCL heifers. No treatment effect on thyroxine concentrations was observed. These data indicate that L did not increase growth. Results from this experiment indicate that supplementing heifers with L was not beneficial and no benefits to supplementing heifers with CTC or the combination of CTC and L were evident compared with control heifers. Heifers in this study experienced minimal health problems and were regarded to be under low stress levels. Supplementing CTC and L may be beneficial to growing heifers under conditions where disease exposure and stressors are greater.

Enzyme immunoassay of testosterone, 17beta-estradiol, and progesterone in perspiration and urine of preadolescents and young adults: exceptional levels in men's axillary perspiration.

Enzyme immunoassays for testosterone, 17beta-estradiol, and progesterone were validated for human facial and axillary perspiration and compared to levels in urine. In study 1, these assays were applied to samples from preadolescent girls and boys and young women and men. Men's axillary perspiration contained substantially higher levels of steroids than seen in other substrates from men or in any sample from women, boys, and girls. Male axillary steroid levels were very variable across individuals, and on average they exceeded levels in facial perspiration by 90-fold for testosterone and 45-fold for estradiol. Men's urinary testosterone also exceeded urinary levels of the other subjects. In study 2, axillary perspiration, urine, and saliva were collected from young men. Substantial axillary levels of testosterone and estradiol were again observed. Correlations of the same hormone among the different substrates were generally very low, except for a small correlation between estradiol levels measured in axillary perspiration and urine in study 2. High unconjugated steroid content in men's axillary excretions could, if absorbed by women during intimacy, be implicated in pheromonal activity.

mtDNA sequence diversity of orangutans from the islands of Borneo and Sumatra.

A comparison of mitochondrial DNA sequences was undertaken for two genes among orangutans from Borneo and Sumatra. The distribution of haplotypes among 42 individuals for NADH dehydrogenease subunit 3 and 39 individuals for cytochrome B was used to infer population structure. The haplotypes among all Bornean orangutans form a cluster of closely related individuals for both genes, with two distinct haplotypes occupying different regions of the island. Sumatran haplotypes fall into three distinct, and highly diverged, groups. Strikingly, one of the Sumatran haplotypes shares sequence identity with the most widespread Bornean haplotype. This haplotype distribution is considered in the context of the highly complex geological history for the area around the Malay Archipelago. Alternating periods of geographic isolation and reunion, resulting from glacially induced land bridge formation, presented substantial opportunity for population dispersal between periodically isolated demes. We present a paleodispersal model that is consistent with genetic, geological, paleoecological, and fossil data. The disparity of sequences present in orangutan populations argues against a simple Sumatra-Borneo dichotomy. Our evidence, and that of others, suggests that the Sumatran population alone contains the remnants of at least three separate lineages.