Specific Gravity of Bovine Colostrum Immunoglobulins as Affected by Temperature and Colostrum Components

Abstract

The effects of temperature and colostrum components on specific gravity in bovine colostrum were investigated. Thirty-nine first milking colostrum samples were collected from Holstein cows. The samples were assayed for alpha-tocopherol, fat, protein, total solids, and IgG. The concentrations of total solids, total protein, total IgG, and fat in colostrum were 26.6, 12.5, 3.7, and 9.4 g/100 g, respectively. A range of 1.8 to 24.7 micrograms/ml for alpha-tocopherol was measured in the colostrum samples. Specific gravity of the colostrum was measured using a hydrometer in increments of 5 degrees C from 0 to 40 degrees C. Specific gravity explained 76% of the variation in colostral total IgG at a colostrum temperature of 20 degrees C. The regression model was improved only slightly with the addition of protein, fat, and total solids. The model for samples at 20 degrees C was IgG (milligrams per milliliter) = 958 x (specific gravity) - 969. Measurement of specific gravity at variable temperatures necessitated inclusion of temperature in the model for estimation of IgG. Inclusion of the other components of colostrum into the model slightly improved the fit. The regression model for samples at variable temperatures was as follows: IgG (milligrams per milliliter) = 853 x (specific gravity) + .4 x temperature (Celsius degrees) - 866.

The effects of calving season and parity on colostrum quality of Holstein cows

“…Average fat concentration of our study (6.89±0.424) was higher than the values reported by Georgiev (2005) and Kehoe et al (2007) (4.6-6.7%) and lower than the findings of Mechor et al (1992), and Abd El-Fattah et al (2012) (8.04-9.4%). The mean protein content of the present study (13.61±0.384) was higher than the findings of Mechor et al (1992) and Georgiev (2005) (11.1-12.5%) and lower than the results reported by Kehoe et al (2007) (14.92%). Current lactose concentration was 2.41±0.11% and such a finding was found to be compatible with the findings of Kehoe et al (2007) (2.49%).…”

“…In present study, means and standard error level of total solid (21.74±0.571) was lower than the findings of Kehoe et al (2007) and Mechor et al (1992) (26.6-27.64%) and higher than the findings of Georgiev (2005) (19.3-18.7%). Average fat concentration of our study (6.89±0.424) was higher than the values reported by Georgiev (2005) and Kehoe et al (2007) (4.6-6.7%) and lower than the findings of Mechor et al (1992), and Abd El-Fattah et al (2012) (8.04-9.4%).…”

“…The specific gravity of colostrum is highly correlated with total solids (Bielmann et al, 2010). But colostrometer is a fragile instrument made of glass and results may not be reliable when refrigerated or warm colostrum was used in quality tests (Mechor et al, 1992). Another indirect measurement method, Brix refractometer, can also be used to assess IgG concentrations through total solids in colostrum solution.…”

The effect of ewe body condition at lambing on growth of lambs and colostral specific gravity

“…Since protein accounts for a high proportion (64 %) of total solids, and gamma globulins represents approximately 47 % of the total protein, SG of colostrum is significantly correlated with Ig concentration (Fleenor and Stott, 1980;El-Loly and Mansour, 2013). However, colostral SG (CSG) is affected by temperature of the colostrum (Mechor et al, 1992) as well as breed, lactation number, and month and year of calving (Morin et al, 2001). Despite some of its deficiencies, the colostrometer is conve-nient for on-farm use for evaluating colostrum as an alternative to labor-intensive, costly and time-consuming methods.…”

Brix Refractometry of Colostrum from Primiparous Dairy Cows and New-Born Calf Blood Serum in the Evaluation of Failure of Passive Transfer

“…The colostrometer was introduced as a practical fi eld tool for measuring IgG concentration in bovine colostrum based on the linear relationship between colostral specifi c gravity and IgG concentration [19]. Although colostrometry allows the producers a fast assessment of colostrum quality, it is often inaccurate [20] because it depends on the colostrum temperature [21,22], cow breed, month of calving and parity [20].…”