Advances in Food Science and Technology

Advances in Food Science and Technology ISSN: 6732-4215 Vol. 4 (2), pp. 001-007, February, 2016. © International Scholars Journals

Review

Effects of heat stress changes in steroid hormone concentrations in peripheral blood of Cattle

*Nasim B. Karimi, Ali Daei Bahar and Abbas Bazargan

Department of Animal Science, Faculty of Agronomy and Animal Science, College of Agriculture and Natural Resources, University of Tehran, P.O.BOX # 31587-4111 Karaj. Iran.

Accepted 10 December, 2015

Abstract

In dairy cows inseminated during the hot months of the year, there is a decrease in fertility. Different factors contribute to this situation; the most important are a consequence of increased temperature and humidity that result in a decreased expression of overt estrus and a reduction in appetite and dry matter intake. Heat stress reduces the degree of dominance of the selected follicle and this can be seen as reduced steroidogenic capacity of its theca and granulosa cells and a fall in blood estradiol concentrations. Plasma progesterone levels can be increased or decreased depending on whether the heat stress is acute or chronic, and on the metabolic state of the animal. These endocrine changes reduce follicular activity and alter the ovulatory mechanism, leading to a decrease in oocyte and embryo quality. The uterine environment is also modified, reducing the likelihood of embryo implantation. Systems activated by heat stress can influence reproduction at the hypothalamus, pituitary gland or gonads. However, the major impact is thought to be within the brain or at the pituitary gland. Measurement of plasma concentrations of the gonadotrophins provides a good indication of the effects at these higher levels, since the pulsatile secretion of luteinizing hormone (LH) is a reflection of the secretion of gonadotropin-releasing hormone (GnRH) from the hypothalamus. Both the secretion and actions of GnRH are influenced by the feedback actions of gonadal sex steroids and inhibin. Recent studies suggest that the use of gonadotropins to induce follicular development and ovulation can decrease the severity of seasonal postpartum infertility in dairy cows.

Key words: Reproductive hormones, dairy cow and heat stress.

Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (12), pp. 001-008, December, 2015. © International Scholars Journals

Full Length Research Paper

A study on aflatoxins and heavy metals in some poultry feeds obtained from the local market in Saudi Arabia

*Ahmed Al-Waleed Salman, Talal Abdulaziz and Ameera Al Gosaibi

Department of Plant Production and Protection, Faculty of Agriculture and Veterinary Medicine, Qassim University, Bureidah, Saudi Arabia.

Accepted 19 August, 2015

Abstract

Aflatoxins and heavy metals were investigated in some poultry feed samples used as starter, grower, developer, layer, rabbit feed and bran which obtained from the local market at Al-Qassim region, Saudi Arabia. The results indicated that different amounts of aflatoxins were found in the analyzed samples. They reached peak values of 70.6, 46.38 and 50.88 µg/kg sample for aflatoxin B1, G1, and G2, respectively, however aflatoxin B2 was generally less than 2.0 µg/kg. The study showed that the levels of aflatoxins were generally below the permissible levels (100 - 200 µg/kg). The results, also indicated that different levels of lead, cadmium, chromium, cobalt, nickel, zinc, manganese, iron and copper were detected in all samples. They ranged from 0.10 - 3.21, 0.004 - 0.249, 0.14 - 1.82, 4.57 - 37.6, 9.77 - 42.93, 0.51 - 55.38, 0.43 - 10.20, 3.78-  5.18, and 0.45 - 3.26 mg/kg for lead, cadmium, cobalt, zinc, manganese, iron, copper, chromium and nickel, respectively. The high levels of zinc, copper, manganese and iron may reflecting the deliberate addition of these metals to meet animal nutrient requirements. Cadmium levels were less than the permissible limit of 0.5 mg/kg in US feeds. Lead levels in most feed sample exceeded the permissible limit of < 1 mg/ kg in UK. However, they lower than the allowed lead content in feed ingredients according to the current official regulations (10 mg/ kg).

Key words: Aflatoxin, heavy metals, feeds, poultry, monitoring.

Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (11), pp. 001-010, November, 2015. © International Scholars Journals

Review

Anti-nutritional factors (ANF) in nutrient utilization in Plant Products for human consumption

*Obadiah Raphel, Adenuga Christian and Agbadugba Nero

Department of Health Promotion and Education, Faculty of Public Health, University of Ibadan, Nigeria.

Accepted 10 May, 2015

Abstract

Anti-nutritional factors (ANF) are compounds which reduce the nutrient utilization and/or food intake of plants or plant products used as human foods or animal feeds and they play a vital role in determining the use of plants for humans and animals. Apart from cyanogenic glycosides, food poisoning arising from anti-nutritional factors, otherwise known as plants’ secondary metabolites has not been properly addressed in most parts of the developing world. People have died out of ignorance, poverty and inadequate nutrition information and education, especially within the African societies. There are reports from time to time of deaths after consumption of some type of beans despite cooking. Also, cases of renal and liver diseases are increasing and this calls for a need to properly address the issue of thorough and adequate processing of foods/feeds before consumption. The aim of this review is to emphasize on the adequate processing of foods/feeds and to educate the people on the dangers of consuming improperly processed foods especially legumes which are reported to contain very high concentrations of anti-nutritional factors.

Key words: Processing methods, anti-nutritional factors, plants, human foods, animal feeds.

Advances in Food Science and Technology ISSN: 6732-4215 Vol. 3 (9), pp. 001-011, September, 2015. © International Scholars Journals

Full Length Research Paper

Effect of Hibiscus sabdariffa L. on circulating levels of reproductive hormones in rabbits (Oryctolagus cuniculus)

*Onuoha Chiamela Frank, Obinna Achebe and Oguname Vincent

Department of Biochemistry, Faculty of Science, Adekunle Ajasin University, Akungba, Ondo State, Nigeria.

Accepted 15 January, 2017

Abstract

Effect of Hibiscus sabdariffa L. (family malvecea) calyx anthocyanin was investigated on circulating levels of reproductive hormones in rabbits (Oryctolagus cuniculus). Forty (40) rabbits (twenty each for male and female) weighing 1.2 ± 0.2 kg were grouped into two control (water control, anthocyanin (delphinidin-3-monoglucoside) standard) and two experimental groups (whole extract (calyces of H. sabdariffa L.) and anthocyanin extract of calyces of H. sabdariffa L). While the water control group received 1.0 ml of water at 0900 h everyday for 28 days at 14:10 light/dark regime, the anthocyanin control and experimental group were administered 200 mg/kg oral doses of the different preparations. Blood samples were drawn prior to administration (day zero) and every seven days at 0900 h for the estimation of serum prolactin, follicle stimulating hormone and testosterone using ELISA. 28-day daily oral administration of delphinidin-3-monoglucoside and anthocyanin-rich extract of H. sabdariffa L. to rabbits is associated with high circulating prolactin in males and non-lactating female rabbits. This may be potentially important in phytotherapuetic induction of milk production in lactating animals. This treatment regime is also associated with lowered circulating FSH in males and female rabbits. Long-term reduction in circulating FSH levels might play important role in failed follicular development in developing female animals and gonadal atrophy in matured animals.

Key words: Hibiscus sabdariffa, anthocyanins, serum prolactin, follicle stimulating hormone, testosterone.