Plasma concentrations of beta-carotene and vitamin A in cows with ovarian cyst

Effect of two postpartum intramuscular treatments with β-carotene (Carofertin®) on the blood concentration of β-carotene and on the reproductive performance parameters of dairy cows

The aim of the study was to determine whether two postpartum intramuscular treatments with 200 mg of beta-(β-)carotene (Carofertin; Alvetra u. Werfft, Vienna, Austria) in a 14-day interval increases β-carotene concentrations in blood, particularly around the time of the first artificial insemination (AI), and to test the effect of the treatment on fertility parameters, luteal size, and progesterone blood levels of dairy cows. A total of 297 Holstein dairy cows were enrolled in the study. Between 28 and 34 days postpartum (dpp) β-carotene concentrations were measured in blood samples using an on-site test (iCheck carotene; BioAnalyt, Teltow, Germany). Cows with a β-carotene concentration <3.5 mg/L, indicating a deficiency of β-carotene, were allocated either to the β-carotene treatment group BCT (n = 123) or to the control group CON (n = 121). Cows with concentrations ≥3.5 mg/L were assigned to an optimally supplied reference group (REF; n = 53). Cows in the BCT group received 200 mg of β-carotene intramuscularly at 28-34 dpp and at 42-48 dpp. Further blood samples were collected at 35-41 dpp, 42-48 dpp, 49-55 dpp, and in the week after the first AI and their β-carotene concentrations were analyzed. Between day 10 and 14 after the first AI, the blood progesterone concentration was measured and the size of the corpus luteum (CL) was determined by ultrasound. Blood β-carotene concentrations increased in the BCT cows in the week after the treatment with a peak at 49-55 dpp and were significantly higher than in the CON group at each time point after the first treatment. Logistic regression models, however, revealed that the treatment with β-carotene had no effect on first service conception rate, days to first service, time to pregnancy, or percentage of pregnant cows within 150 dpp. Furthermore, there was no effect on progesterone concentration or the size of the CL between the groups. In conclusion, two treatments with Carofertin postpartum increased β-carotene blood concentrations but had no effect on the fertility parameters in this study.

Nutritional strategies in ruminants: A lifetime approach

This review examines the role of nutritional strategies to improve lifetime performance in ruminants. Strategies to increase ruminants' productive longevity by means of nutritional interventions provide the opportunity not only to increase their lifetime performances and their welfare, but also to decrease their environmental impact. This paper will also address how such nutritional interventions can increase herd efficiency and farm profitability. The key competencies reviewed in this article are redox balance, skeletal development and health, nutrient utilization and sustainability, which includes rearing ruminants without antibiotics and methane mitigation. While the relationships between these areas are extremely complex, a multidisciplinary approach is needed to develop nutritional strategies that would allow ruminants to become more resilient to the environmental and physiological challenges that they will have to endure during their productive career. As the demand of ruminant products from the rapidly growing human world population is ever-increasing, the aim of this review is to present animal and veterinary scientists as well as nutritionists a multidisciplinary approach towards a sustainable ruminant production, while improving their nutrient utilization, health and welfare, and mitigation of their carbon footprint at the same time.

Role of oxidant–antioxidant balance in reproduction of domestic animals

Reproductive process leads to dynamic changes in metabolism and energy consumption, which may be responsible for the excessive production of free radicals (oxidants) that are generated during the physiological process of oxygen consumption. As the ovary is a metabolically active organ, it produces oxidants. Growing follicles, granulose cells of Graffian follicles and ovulated follicles all produce both enzymatic and non-enzymatic antioxidants to preserve themselves from the oxidative damage of oxidants. Oxidants and antioxidants are involved in several reproductive functions such as the regulation of follicular fluid environment, folliculogenesis, steroidogenesis, corpus luteum function, and luteolysis. In this article, the currently available literature is reviewed in relation to the roles of oxidants and oxidative stress in both normal and abnormal reproductive physiological processes.

Accumulation of xanthophylls from the phaffia yeast (Xanthophyllomyces dendrorhrous) in calves

An investigation into the absorption and accumulation of carotenoids from phaffia yeast in two to three-week-old calves was carried out. Carotenoid contents of the control cattle (n=1) were 615.0 ng/g in the liver, 263.7 ng/g in the duodenum, 218.0 ng/g in the pancreas, 170.0 ng/g in the blood, 140.3 ng/g in the jejunum, 115.0 ng/g in the spleen. Among the accumulated carotenoids, β-carotene was presented as a major component (86.0 to 94.3%) along with lutein (5.7 to 14.0%) as a minor component. On the other hand, carotenoid contents in phaffia yeast-supplemented (5 g/day for one month) calves (n=3) were 4 to 10 times higher than those of the control calf. Carotenoid contents of phaffia yeast-supplemented calves were 2570.1±782 ng/g in the liver, 1806.6±1064 ng/g in the pancreas, 1648.4±630.2 ng/g in the spleen, and 1255.9±300.2 ng/g in the blood. In addition to β-carotene, keto-carotenoids from phaffia yeast, echinenone, (3R)-3-hydroxyechinenone, and (3R,3'R)-astaxanthin, were accumulated in all organs of phaffia yeast-supplemented calves. β-Carotene and (3R)-3-hydroxyechinenone were present as major carotenoids followed by echinenone. However, (3R,3'R)-astaxanthin, which was the major carotenoid in phaffia yeast, was found to be a minor carotenoid in calves. This indicated that calves well absorbed fewer polar xanthophylls, echinenone and (3R)-3-hydroxyechinenone compared to the polar xanthophyll, astaxanthin.

Relationship between embryo collection results after superovulation treatment of Japanese Black cows and their plasma β-carotene and vitamin concentrations

The objective of this study was to investigate the relationship between the plasma concentrations of vitamin A (VA), vitamin E (VE) and β-carotene (BC) during embryo collection in Japanese Black cows that had undergone superovulation treatment and the embryo collection results. Following superovulation treatment in 116 Japanese Black cows, we collected 1317 embryos by nonsurgical means seven days after artificial insemination. The collected embryos were classified into transferable embryos, unfertilized oocytes and degenerated embryos. After embryo collection, we collected blood samples from the cows and measured the plasma concentrations of VA, VE and BC. The cows were then divided into 2 groups depending on the plasma concentration of VA (L and H: < 80 IU/dl and ≥ 80 IU/dl), VE (L and H: < 150 µg/dl and ≥ 150 µg/dl) and BC (L and H: < 150 µg/dl and ≥ 150 µg/dl). As a result, the number of collected embryos in the H group of VE was significantly (P<0.01) higher than that in L groups. Furthermore, the number of transferable embryos was higher (P<0.05) in all VA, VE and BC H groups than in the L groups. The H group for BC showed a high ratio of transferable embryos compared with the L group (P<0.05). Consequently, the present study suggests that the plasma VE and BC concentrations are positively correlated with the embryo collection results.

Effects of high density lipoprotein containing high or low beta-carotene concentrations on progesterone production and beta-carotene uptake and depletion by bovine luteal cells

Luteal cells were isolated from mid-luteal heifer ovaries by collagenase digestion. Cells were cultured with DMEM/Ham's F12 medium in serum pre-treated plastic culture dishes for periods of up to 11 days. As beta-carotene is almost completely insoluble in all polar solvents, it was added to cultures in either dimethyl sulphoxide (DMSO), tetrahydrofuran (THF) or as high-density lipoprotein (HDL) containing high or low beta-carotene concentrations. Medium was replaced after 24 h, thereafter medium was changed every 48 h. Treatment of cells with DMSO alone or with beta-carotene (5 micromol/l) in DMSO both resulted in significant (P<0.01) stimulation of progesterone production. beta-Carotene (5 micromol/l) in THF did not alter progesterone production but 50 micromol/l beta-carotene in THF resulted in significant inhibition (P<0.02) of progesterone production on days 3 and 7. Cultures were also supplemented with bovine HDL preparations containing equal concentrations of cholesterol (25 microg/ml) but high or low beta-carotene (12.4 or 0.44 microg/mg of cholesterol). Both HDL preparations significantly stimulated progesterone production (P<0. 001) but the high beta-carotene HDL was significantly (P<0.02) more effective than the low beta-carotene HDL. However, when given together with bovine luteinizing hormone (bLH) or dibutyryl cAMP (dbcAMP), the high beta-carotene HDL stimulated progesterone production less than did the low HDL (P<0.01). Uptake and depletion of beta-carotene by luteal cells were also examined in culture. beta-Carotene supplementation increased luteal cell beta-carotene from an initial level of 373 ng per 10(6) cells to 2030 ng per 10(6) cells by day 6. In contrast, the levels in control cells decreased to 14% of starting values during the same period. Cells treated with HDL containing high beta-carotene on day 1 or days 1 and 3 were then incubated with or without bLH or dbcAMP for a further 2 days to investigate the effect of bLH and dbcAMP on depletion of beta-carotene by luteal cells. beta-Carotene depletion in the luteal cells was significantly higher (P<0.05) in LH- and dbcAMP-treated cells than in the control cells in both groups. These results indicate that the use of solvents such as DMSO or THF may have undesirable effects due to alteration of cell membrane permeability. Supplementation with bLH or dbcAMP may increase the metabolism of beta-carotene in luteal cells. bLH or dbcAMP together with high beta-carotene HDL may, when combined with the effect of increased beta-carotene metabolism, give less stimulation than with low beta-carotene HDL.