Effect of high-pressure processing of bovine colostrum on immunoglobulin G concentration, pathogens, viscosity, and transfer of passive immunity to calves

Abstract

This study aimed to determine the effects of high-pressure processing on the immunoglobulin concentration, microbial load, viscosity, and transfer of passive immunity to calves when applied to bovine colostrum as an alternative to thermal pasteurization. A pilot study using Staphylococcus aureus was conducted to determine which pressure-time treatments are most appropriate for use with bovine colostrum, with the goals of maximizing bacterial inactivation while minimizing IgG content and viscosity changes. Following the pilot study, an inoculation study was conducted in which first-milking colostrum samples from Holstein-Friesian cows were inoculated with known concentrations of various bacteria or viruses and pressure processed at either 300 MPa for up to 60min or at 400MPa for up to 30min. The recovery of total native aerobic bacteria, Escherichia coli, Salmonella enterica ssp. enterica serovar Dublin, Mycobacterium avium ssp. paratuberculosis, bovine herpesvirus type 1, and feline calicivirus were determined after processing. Colostrum IgG content was measured before and after pressure processing. Shear stress and viscosity for each treatment was determined over shear rates encompassing those found during calf feeding and at normal bovine body temperature (37.8°C). Following a calf trial, serum IgG concentration was measured in 14 calves fed 4 L of colostrum pressure processed at 400MPa for 15min. In the pilot study, S. aureus was effectively reduced with pressure treatment at 300 and 400MPa (0, 5, 10, 15, 30, and 45min), with 2 treatments at 400MPa (30, 45min) determined to be inappropriate for use with bovine colostrum due to viscosity and IgG changes. High-pressure processing at 300MPa (30, 45, and 60min) and 400MPa (10, 15, and 20min) was shown to effectively reduce total native aerobic bacteria, E. coli, Salmonella Dublin, bovine herpesvirus type 1, and feline calicivirus populations in bovine colostrum, but no decrease occurred in Mycobacterium avium ssp. paratuberculosis. All inoculation study pressure treatments insignificantly decreased IgG content of colostrum. Treatment of colostrum at 400MPa for 15min during the calf trial decreased IgG content of colostrum. Treatment at 400MPa for 15min increased colostrum viscosity, with 2 of 14 samples requiring dilution with water for calf feeding. Calves fed pressure-processed colostrum had similar serum IgG but lower efficiency of absorption than calves fed heat-treated colostrum. The results of this study suggest that high-pressure processing of bovine colostrum maintains an acceptable IgG level while decreasing bacterial and viral counts. Changes in viscosity sometimes made calf feeding more difficult, but still feasible. Additional research to optimize this technology for on-farm use is necessary.

A Scoping Review of On-Farm Colostrum Management Practices for Optimal Transfer of Immunity in Dairy Calves

“…Up to 300 MPa, IgG remained intact, but application of 400 MPa resulted in altered viscosity of the colostrum and denaturation of IgG ( 83 ). Indyk et al ( 84 ) and Foster et al ( 85 ) found colostral IgG to be stable up to 400 MPa treatment, as long as duration was limited to 30 min. Increasing pressure (500 or 600 MPa) or duration resulted in increased denaturation and aggregation ( 85 ).…”

“…Indyk et al ( 84 ) and Foster et al ( 85 ) found colostral IgG to be stable up to 400 MPa treatment, as long as duration was limited to 30 min. Increasing pressure (500 or 600 MPa) or duration resulted in increased denaturation and aggregation ( 85 ). Apparently, IgG in colostrum is more stable compared to IgG isolated from colostrum.…”

Potential Benefits of Bovine Colostrum in Pediatric Nutrition and Health

“…Processing procedures differentially reduce the content of many bioactive factors in BC [ 225 , 232 , 254 , 276 ], and while this may decrease in vivo bioactivity, it does not eliminate it, partly due to the high amounts present in native BC before processing. Igs and LF are relatively sensitive to heat damage, while other bioactive peptides, such as IGF-1 and TGF-β, are less sensitive [ 276 , 277 , 278 ]. Consequently, IgG and LF are often used as markers of BC bioactivity.…”

Applications of novel processing technologies to enhance the safety and bioactivity of milk

“…Reduction obtained for specific strains Reference 900 MPa at 100 • C for 6 min Commercially sterile UHT milk (2% fat), pH > 4.6 ∼1.5 log CFU/mL for C. sporogenes PA 3679 (ATCC 7955) spores, and a further 4 log CFU/mL reduction when an insulator was used in the setup (Shao et al, 2010) 900 MPa at 100 • C for 5 min (with insulator) (Foster et al, 2016) 450 MPa for 15 min at 21 • C Human milk 7.1 log CFU/mL for E. coli, 6.83 log CFU/mL for S. aureus, 7.91 log for L. monocytogenes, 5.9 log for C. sakazakii, and 5.3 log for B. cereus cells (not tested for presence of spores) (Jarzynka et al, 2021) further investigation using Fourier transform infrared (FT-IR) spectroscopy, it was found that germination was presumably associated with reversible gelling of the inner membrane (Georget, Kapoor, et al, 2014). Hence, in hurdle technologies when HPP is combined with temperature (30 • C -55 • C), the possibility of inducing germination cannot be ruled out (Paredes-Sabja et al, 2011).…”