Agricultural Research Center (Egypt)
Biotechnology
PERIPARTUM CONCENTRATIONS OF LEPTIN HORMONE IN BLOOD PLASMA AND MILK SERUM OF FRIESIAN COWS Hussein Y. S.1; I. M. Abd El-Razek2; Zenat B. Rabie1, and I. S. El-Shamaa2 1 Animal Production Research Institute, Agricultral Research Center,... more
PERIPARTUM CONCENTRATIONS OF LEPTIN HORMONE IN
BLOOD PLASMA AND MILK SERUM OF FRIESIAN COWS
Hussein Y. S.1; I. M. Abd El-Razek2; Zenat B. Rabie1, and I. S. El-Shamaa2
1 Animal Production Research Institute, Agricultral Research Center, MOA,
Egypt.
2 Kafrelsheikh University, Faculty of Agriculture, Animal Production
Department.
ABSTRACT
Ten multiparous Friesian cows (459.0±43.9kg) one month before calving from the second to
the fourth parities were used in the current study. Cows were milked twice daily and milk yield (on
basis of 3.5% fat corrected) was estimated. Milk constituents were determined. Some blood
constituents were measured colorimetrically meanwhile plasma triiodothyronine (T3) was determined
using direct single antibody radioimmunoassay (RIA) whereas leptin analysis was done using DRG®
leptin (Sandwich) ELISA.
Plasma Leptin concentration started to decrease one month pre-partum and reached 3.29 ng/dl;
at parturition and continued in low level during postpartum period reached nadir levels at 60 days
postpartum (2.71ng/dl). Plasma leptin concentration correlated positively with plasma cholesterol
(r=0.31; P<0.0173) and negatively with milk solid not-fat yield (r=-0.26; P<0.0985) and milk protein
yield (r=-0.28; P<0.0695). Also, significant correlation were found between milk serum leptin and
plasma glucose levels (r=0.39; P<0.0415). There is an insignificant negative correlation between
plasma leptin and milk serum leptin concentrations (r=-0.09). Generally, Lepin might be functioning as
an autocrine or paracrine regulating signal at the level of the mammary gland tissue.
Keywords: Leptin Hormone, Peripartum, Lactation, Pregnant Cows.
Corresponding author: Dr. Y.S. Hussein: yshussein@hotmail.com
BLOOD PLASMA AND MILK SERUM OF FRIESIAN COWS
Hussein Y. S.1; I. M. Abd El-Razek2; Zenat B. Rabie1, and I. S. El-Shamaa2
1 Animal Production Research Institute, Agricultral Research Center, MOA,
Egypt.
2 Kafrelsheikh University, Faculty of Agriculture, Animal Production
Department.
ABSTRACT
Ten multiparous Friesian cows (459.0±43.9kg) one month before calving from the second to
the fourth parities were used in the current study. Cows were milked twice daily and milk yield (on
basis of 3.5% fat corrected) was estimated. Milk constituents were determined. Some blood
constituents were measured colorimetrically meanwhile plasma triiodothyronine (T3) was determined
using direct single antibody radioimmunoassay (RIA) whereas leptin analysis was done using DRG®
leptin (Sandwich) ELISA.
Plasma Leptin concentration started to decrease one month pre-partum and reached 3.29 ng/dl;
at parturition and continued in low level during postpartum period reached nadir levels at 60 days
postpartum (2.71ng/dl). Plasma leptin concentration correlated positively with plasma cholesterol
(r=0.31; P<0.0173) and negatively with milk solid not-fat yield (r=-0.26; P<0.0985) and milk protein
yield (r=-0.28; P<0.0695). Also, significant correlation were found between milk serum leptin and
plasma glucose levels (r=0.39; P<0.0415). There is an insignificant negative correlation between
plasma leptin and milk serum leptin concentrations (r=-0.09). Generally, Lepin might be functioning as
an autocrine or paracrine regulating signal at the level of the mammary gland tissue.
Keywords: Leptin Hormone, Peripartum, Lactation, Pregnant Cows.
Corresponding author: Dr. Y.S. Hussein: yshussein@hotmail.com
Leptin is a newly discovered hormone; well known as metabolism modifier; secreted by adipose tissue. The role/s of leptin in mammary gland functions still inscrutable and unclear. Current book sheds the light on the Hormonal profile of... more
Leptin is a newly discovered hormone; well known as metabolism modifier; secreted by adipose tissue. The role/s of leptin in mammary gland functions still inscrutable and unclear. Current book sheds the light on the Hormonal profile of leptin around parturition in blood plasma and milk serum, and its relationship with blood plasma components and mammary gland function; in addition to the relation between plasma leptin and milk serum leptin concentrations in Friesian dairy cows under the Egyptian conditions. It is likely that leptin directs nutrients towards organs or tissues that are metabolically more active as well mammary gland, functioning as an autocrine or paracrine regulating signal. Leptin is an interesting hormone for scientists and pharmaceutical companies to manipulate; wishing to improve productive performance of animals. Furthermore, if leptin is involved in animal responses to disease or stress, further manipulation may become an important therapy in the treatment of animal disease. However, direct leptin treatment will not be feasible in livestock production unless affordable, potent analogs or delivery systems are developed.
The aim of this study was to evaluate the effect of addition of epidermal growth factor (EGF) to culture medium of fresh and vitrified rabbit embryos on formation rate into blastocysts/hatched blastocysts and quality of the embryos. Total... more
The aim of this study was to evaluate the effect of addition of epidermal growth factor (EGF) to culture medium of fresh and vitrified rabbit embryos on formation rate into blastocysts/hatched blastocysts and quality of the embryos. Total of 16 mature NZW rabbit does were superovulated by PMSG and hCG. Embryos were recovered 64-66 h post-mating by flushing from the oviducts of the slaughtered animals. Compact morulae were used in this study. Embryos were divided into two groups, fresh (n=200) and intended for vitrification (n=185). Fresh (n=200) or vitrified embryos (n=150) were in vitro cultured. Either fresh or vitrified embryos were in vitro cultured in medium supplemented with EGF (n=100 and 75) as compared to control medium (n=100 and 75), respectively, under mineral oil in CO2 incubator at 38°C, 95% humidity and 5% CO2 in air. Embryos were assessed daily to record the developmental competence of embryos in term of formation rate of embryos at blastocyst from morula stage, from blastocyst to expanded blastocyst stage or from expanded to hatched blastocyst throughout 5 days as culture period. Total cell number and intrazonal diameter of blastocysts were determined. Results showed that formation rate of blastocyst (BLs), expanded BLs and hatched BLs was the highest (P<0.05) for fresh embryos cultured with EGF (86.00, 94.11 and 88.92%), moderate for fresh embryos without EGF (74.00, 81.11 and 75.23%) or those vitrified with EGF (70.62, 80.67 and 73.89%), and the lowest for vitrified embryos cultured without EGF (57.76, 70.00 and 56.76%). Adding EGF in culture medium increased (P<0.05) total cell number and intrazonal diameter of blastocysts produced from fresh (121.20/BLs and 129.2 µm) or vitrified (118.2/BLs and
- by Dr-Yasser Hussein and +1
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- Embryology