TY  - BOOK
AU  - Shibu K Jacob 
AU  - Philomina P T (Guide)
TI  - Assessment of mineral status during pregnancy in crossbred cattle
U1  - 636.089 2 
PY  - 2000///
CY  - Mannuthy
PB  - Department of Physiology, College of Veterinary and Animal Sciences
N2  - Twenty, healthy crossbred heifers stationed at Kerala Agricultural 
University - Cattle Breeding Farm, Thumburrnuzhi, were utilized for the study. 
The parameters estimated in the experimental animals comprise of serum profile 
of certain macro and microelements as calcium, phosphorus, magnesium, sodium, 
.potassium, iron, copper, zinc and haematological parameters like red blood cells 
count, haemoglobin content, volume of packed red cells and erythrocyte indices 
before conception and at different stages of pregnancy viz., from third month to 
ninth month at monthly intervals and first month of lactation. 
The serum calcium level showed significant variations during the period of 
study, which decreased from the control level till fifth month of pregnancy and 
then increased from sixth month of gestation and reached the highest level by 
ninth month of gestation thereafter, decreased during first month of lactation 
(table 1). The increased serum calcium level from sixth month of pregnancy and 
early lactation could be due to an increased demand of this element for the 
formation of fetal skeleton and organogenesis as well as for drainage into the milk 
Serum inorganic phosphorus concentration was increased from third month of 
pregnancy and the highest level was attained by fifth month of pregnancy. Later 
the level of serum inorganic phosphorus gradually declined from sixth month to 
ninth month of pregnancy. These fluctuations in serum phosphorus during 
pregnancy might be due to the mobilisation of calcium and phosphorus from the 
dam's skeleton or due to an increased G.I tract absorption during the period. 
 
Besides the utilisation of calcium for fetal growth, calcium and phosphorus play a 
vital role in the action of hormones and enzymes at subcellular levels in an 
integrated fashion in reproduction of young heifers. During first month of early 
lactation still lower content of serum inorganic phosphorus was observed which 
could be due to its drainage into milk. There was an increase in the serum 
magnesium concentration from the preconception level during different stages of 
pregnancy and the same was significantly higher from sixth to ninth month of 
pregnancy which later dropped a little during first month of lactation as observed 
in the case of serum calcium. The increased magnesium level during the period of 
gestation could be due to the increased gut absorption in order to meet increased 
metabolic demands of this mineral, as many of the enzymes of glycolysis and 
citric acid cycle require magnesium as a cofactor. The serum concentration of 
sodium' showed an increasing tendency whereas that of potassium showed a 
decreasing tendency from third to ninth month of pregnancy. However the values 
of sodium encountered during third to sixth month and that of potassium from 
third to eighth month of pregnancy were lower than pre conception values which 
might be due to an increased permeation of these electrolytes into the uterus and 
fmally drainage into the fetoplacentary unit. The serum sodium and potassium 
level reached highest values during ninth month of pregnancy which further 
decreased during first month of lactation due to an increased transfer of these 
electrolytes into milk .. An increasing trend was observed for serum levels of iron 
and copper from third to fifth month of pregnancy. The increased level of serum 
iron during the first half of pregnancy might be due to an increased absorption 
 
from the gastrointestinal tract. It was observed that both these minerals reach their 
peak serum level by fifth month of pregnancy and towards late pregnancy the iron 
level decreased which might be either due to its incorporation into the fetus or an 
increase in plasma volume so that haemoglobin content of blood also got 
apparently decreased. Serum copper concentration which decreased during the 
period of sixth to eighth month of pregnancy might be due to an increased blood 
volume and further increase in serum copper level during the ninth month of 
pregnancy might be due to the increase in estrogen level during that period as 
estrogen induce denovo synthesis of ceruloplasmin and thereby increased serum 
copper value during this period. During the first month of postpartum, serum iron 
level was found decreased while copper concentration increased. As far as serum 
zinc levels was concerned it was noticed that throughout the pregnancy its level 
increased when compared to control value. This could be due to an increased 
concentration of several enzymes involved in steroidgenesis and carbonic 
anhydrase, a zinc containing enzyme encountered during pregnancy. Eventhough 
serum zinc content exhibited a decreasing trend from third to eighth month of 
gestation, eventually it got increased during ninth month which might be due to 
higher levels of circulating prostaglandins during this period as zinc is required for 
their transport. A further increase in serum zinc level was noticed during first 
month of lactation. 


UR  - http://krishikosh.egranth.ac.in/handle/1/5810104537
ER  -