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The uptake of [Beta]-carotene by reproductive tissues and the effects of [Beta]-carotene on reproductive function in the dog are unknown. We studied the uptake of [Beta]-carotene by blood, corpus luteum, and uterine endometrium and the role of dietary [Beta]-carotene in influencing ovarian steroid and uterine protein production during the estrous cycle in the dog. Mature female Beagle dogs (n = 56) were fed diets containing 0, 2, 20, or 50 mg of [Beta]-carotene daily for approximately 6 wk before estrus detection. Blood was sampled at regular intervals from estrus through d 45 after ovulation (d 0 = ovulation), when laparotomy was performed. The ovaries were obtained for the isolation of corpus luteum. The uterus was flushed with phosphate-buffered saline and the endometrium obtained by scraping. [Beta]-Carotene was not detectable in plasma, corpus luteum, or endometrium of unsupplemented dogs. However, [Beta]-carotene and [Alpha]-carotene in plasma, corpus luteum, and uterine endometrium increased in a dose-dependent manner. [Alpha]-Carotene made up a high percentage of total carotenoids even though the [Alpha]-carotene content in the dietary source was very low. Dogs fed 50 mg of [Beta]-carotene had significantly higher concentrations of plasma progesterone between d 12 and 26 compared with unsupplemented dogs. Dietary [Beta]-carotene did not influence plasma estradiol-17[Beta] and total uterine proteins. Therefore, [Beta]-carotene is absorbed into plasma, corpus luteum, and uterine endometrium of dogs. Furthermore, dietary [Beta]-carotene increased plasma progesterone concentrations during the estrous cycle. It is possible that dietary [Beta]-carotene may improve reproductive function in the canine. Key Words: [Beta]-Carotene, Dogs, Estrous, Steroids, Uptake

Three experiments were conducted to study the uptake of oral beta-carotene by blood plasma and leukocytes in domestic cats. In Experiment 1, mature female Tabby cats (12 mo old) were given once orally 0, 10, 20 or 50 mg of beta-carotene and blood taken at 0, 12, 24, 30, 36, 42, 48 and 72 h after dosing. Concentrations of plasma beta-carotene increased in a dose-dependent manner. Peak concentrations were observed at 12-24 h and declined gradually thereafter. The half-life of plasma beta-carotene was 12-30 h. In Experiment 2, cats were dosed daily for six consecutive days with 0, 1, 2, 5 or 10 mg beta-carotene. Blood was sampled once daily at 12 h after each feeding. Daily dosing of cats with beta-carotene for 6 d resulted in a dose-dependent increase in circulating beta-carotene. Experiment 3 was designed to study the uptake of beta-carotene by blood leukocytes. Cats were fed 0, 5 or 10 mg of beta-carotene daily for 14 d. Blood leukocytes were obtained on d 7 and 14 to determine beta-carotene content in whole lymphocytes and in subcellular fractions. Blood lymphocytes took up large amounts of beta-carotene by d 7 of feeding. Furthermore, beta-carotene accumulated mainly in the mitochondria (40-52%), with lower amounts accumulating in the microsomes (20-35%), cytosol (15-34%), and nuclei (1.5-6%). Therefore, domestic cats readily absorb beta-carotene across the intestinal mucosa and transfer the beta-carotene into peripheral blood leukocytes and their subcellular organelles. beta-Carotene uptake kinetics show that some aspects of beta-carotene absorption and metabolism in cats are similar to those of humans. [ABSTRACT FROM AUTHOR]

beta-Carotene uptake by blood plasma and leukocytes was studied in mature beagle dogs. In expt. 1, dogs were fed once orally with 0, 50, 100 or 200 mg of beta-carotene and their blood was sampled at 0, 1. 5, 3, 6, 10, 18 and 24 h. Plasma beta-carotene concentrations increased dose-dependently to peak at 6 h postfeeding. Concentrations decreased rapidly thereafter, showing a half-life of 3 to 4 h. In expt. 2, dogs were given daily doses for seven consecutive days with 0, 12.5, 25, 50 or 100 mg beta-carotene. Plasma beta-carotene concentrations increased dose-dependently; concentrations after the last dose were two- to fourfold higher than after the first dose. In expt. 3, dogs were fed 0, 50 or 100 mg beta-carotene daily for 30 d. beta-Carotene was elevated in lymphocytes and neutrophils in supplemented dogs. Furthermore, beta-carotene was taken up by the cytosol, mitochondria, microsomes (lymphocytes and neutrophils) and nuclei (lymphocytes only), proving that dogs can absorb beta-carotene. beta-Carotene is taken up by subcellular organelles of blood lymphocytes and neutrophils and in the plasma and leukocytes beta-carotene may have physiological importance as it relates to immunity in dogs. Uptake kinetics indicated that dogs are not an appropriate animal model for studying beta-carotene absorption and metabolism in humans. [ABSTRACT FROM AUTHOR]

The hydrogen storage properties of LiBH4 ball milled with various ratios of carbon nanotubes (Cnano) were investigated. The LiBH4/Cnano mixtures showed superior dehydrogenation, hydrogen desorption starting at 250 °C, and the majority of hydrogen being released below 600 °C. The rehydrogenation results revealed that the Li2C2, formed during the dehydrogenation, could be reversed to LiH, in which the hydrogen capacity corresponds to 1/4 of the original hydrogen content of LiBH4, and C at 10 MPa hydrogen pressure and 400 °C. [ABSTRACT FROM AUTHOR]

This study determined the caponization effects on the immune responses in male chicks. Different forms of exogenous androgen implantation on male chick immunity were compared. Healthy, uniform male Single Comb White Leghorn chicks were caponized at 3 wk of age. Birds were housed in individual cages (35 x 30 x 40 cm, length x width x height). Each of 27 shamoperated (sham) and caponized (capon) male chickens were used for trial 1. Trial 2 used 60 capons divided into 4 treatments with implants of either 1 mm i.d. x 3 mm o.d. 58 mg of cholesterol, testosterone (TES), 5α-dihydrotestosterone (5α-DHT), or 19-nortestosterone (19-NorT). The exogenous androgen was implanted immediately after caponization and resupplied every 4 wk for an entire 13-wk feeding trial. The results from trial 1 showed that the relative bursa weight increased compared with the sham treatment (P < 0.05). The 2 wk post-Newcastle disease virus titer and the delayed-type hypersensitivity (DTH) of 48 h post-phytohemagglutinin phosphate (PHA-P) injection were increased compared with the sham treatment (P < 0.05). In trial 2, implanted 5α-DHT and 19-NorT could decrease the relative bursa weight in capons (P < 0.05). The 2 wk post-Newcastle disease virus titer in the 5α-DHT group was higher than that in the cholesterol group (P < 0.05). The 19-NorT group had the highest (P < 0.05) PHA-P response. Peripheral blood lymphocyte subset population analysis revealed that the percentage of CD4 T cells in the TES group was lower (P < 0.05) compared with that of the 5α-DHT group. Differently, the percentage of CD8 T cells in the TES and 19-NorT groups was higher (P < 0.05) than that in the 5α-DHT group. Male chicks that were caponized had increased bursa weight and PHA-P response, whereas different forms of exogenous androgen implantation reverted the phenomena in an order of potency of 5α-DHT and 19-NorT > TES, and the PHA-P response was TES > 5α-DHT >19-NorT. [ABSTRACT FROM AUTHOR]

This study examined the effects of caponization using different doses of testosterone (TES) on sexuality, hematology, and immune responses in male chickens. Healthy male chickens were caponized at 12 wk of age and selected at 16 wk of age for a 10-wk experiment. Fifteen intact male and 15 caponized male chickens were assigned to trial 1. In trial 2, ten shamoperated male chickens (sham) and 40 capons (randomly divided into 4 treatments) were implanted with cholesterol (CHOL, 9.24 ± 0.36 mg), low TES (5.88 ± 0.23 mg), medium TES (9.81 ± 0.17 mg), or high TES (16.7 ± 0.24 mg) administered at 16, 20, and 24 wk of age. Results from trial 1 showed caponization decreased the comb length, height and weight, and hematocrit (P < 0.05) and increased the hemagglutination inhibition (HI; 1 wk postchallenge) and hemagglutination titer after Newcastle disease virus (NDV) and SRBC injections (P < 0.05). In trial 2, the medium TES increased the comb length and height as compared with the CHOL group. Only the high TES increased the comb weight (P < 0.05). The HI titer (1 wk postchallenge) in the CHOL group was higher than the sham (P < 0.05). The medium TES decreased the HI titer (P < 0.05) to the level of the sham (P > 0.05). The phytohemagglutinin response was higher in the high TES group 24 h postinjection (P < 0.05) and in the medium TES 48 h postinjection (P < 0.05) as compared with the CHOL group. High dose TES implantation decreased the white blood cell counts as compared with the CHOL and sham groups (P < 0.05). It appears that caponization decreased the blood androgen concentration and enhanced the humoral (anti-NDV and anti-SRBC) immune response. Testosterone implantation up to a threshold concentration could inhibit the humoral (anti-NDV) immune response and increase the cell-mediated (phytohemagglutinin) immune response. [ABSTRACT FROM AUTHOR]

Nontyphoid Salmonella have a broad host range in poultry and mammals, and serovar Typhimurium is a threat to public health. In this study, normal and sick ducks and geese were collected from 12 farms in Taiwan to investigate the age-associated infection of Salmonella and Salmonella Typhimurium in Roman geese (Anser anser domesticus) and Pekin ducks (Anas platyrhynchos domesticus). In normal birds, the prevalence of Salmonella differed between species, and with age [e.g., 1-wk group, 37.5% (30/80) for ducks and 5.2% (6/116) for goslings (P < 0.05) vs. 4-wk group, 1% (1/96) for ducks and 12.1% (21/174) for geese]. Salmonella Typhimurium was identified from the visceral organs of moribund young geese suffering with colibacillosis and riemerellosis isolated from 2 goose farms (farm A and B, respectively). At farm B, 22.9% (27/118) of 4-wk geese with diarrhea were Salmonella Typhimurium-positive compared with 4.6% (8/174) of 4-wk normal geese. All Salmonella Typhimurium strains except one harbored a 94.7-kb virulence plasmid. Subcutaneous injection of Salmonella Typhimurium isolate 91NGL1 resulted in different clinical signs and pathogenesis between ducks and geese. In addition, the mean infectivity dose ratios of ducks to geese were 3.2 and 85.0 for 4- and 12-d birds, respectively, suggesting that goslings were more susceptible to Salmonella Typhimurium and resistance to Salmonella Typhimurium increased with age, especially for ducks. Therefore, Salmonella Typhimurium infection should be more common in goose farms than in duck farms, especially in the younger birds. [ABSTRACT FROM AUTHOR]

Salmonella enterica serovar Enteritidis is the major zoonotic and intracellular pathogen. Different strategies have been developed to prevent the S. Enteritidis infection. The beta-1,3-1,6-glucan of Schizophyllum commune was used as an immunological booster to determine the minimal dietary level of beta-glucan that would restrict S. Enteritidis infection through the effects of beta-glucan on the activity of macrophages and direct physical protection of the intestine. One-day-old male Single Comb White Leghorn chicks were used in all trials. In trials 1 and 2, the 0.1% beta-1,3-1,6-glucan treatment completely eliminated the viable S. Enteritidis from spleen and liver in an oral challenge of 10(8) S. Enteritidis without any harmful effect on BW, serum proteins, and immunoglobulin. Instead of a 21-d feeding period of beta-glucan, a 14-d treatment was enough to eliminate the S. Enteritidis in spleen and liver. In trial 3, an increase in the relative weight of bursa of Fabricius and phytohemagglutinin-P-inducing cutaneous basophil hypersensitivity was observed (P < 0.05). In trials 2, 3, and 4, the direct or indirect effect of beta-1,3-1,6-glucan on abdominal macrophages was examined. Sterilized 3% Sephadex G-50 was injected to induce abdominal (peritoneal) phagocytes in chicks fed with or without 0.1% beta-1,3-1,6-glucan. Significantly increased phagocytic and bactericidal capability to S. Enteritidis was found in abdominal macrophages either pretreated or in vitro treated with 0.1% beta-1,3-1,6-glucan. In conclusion, in addition to the physical properties to block S. Enteritidis entrance, 0.1% dietary beta-1,3-1,6-glucan may enhance the host defense to S. Enteritidis by directly upregulating the phagocytosis and bactericidal activity of abdominal macrophages in chicks.