Immunoglobulin concentrations in feline colostrum and milk, and the requirement of colostrum for passive transfer of immunity to neonatal kittens

Abstract

The purpose of this study was to clarify whether cats have a colostral and milk phase of lactation differentiated by concentrations of immunoglobulins, and whether colostrum ingestion by newborn kittens is essential for optimal transfer of passive immunity. Milk from specific pathogen-free queens was analyzed for IgG and IgA concentrations from parturition through 6 weeks of lactation. Serum IgG and IgA concentrations from birth through 8 weeks of age were determined for colostrum-fed kittens, colostrum-deprived kittens that were fed a milk replacer, and colostrum-deprived kittens that were fostered onto queens in the milk phase of lactation. The total IgG and IgA concentrations in milk were significantly higher on the day of parturition than on day 7 of lactation, indicating cats do have a colostral phase of lactation. The predominant immunoglobulin in both colostrum and milk was IgG. The serum IgG concentrations in colostrum-deprived kittens fostered on queens in the milk phase of lactation were similar to colostrum-deprived kittens fed a milk replacer, and the concentrations were significantly lower than in colostrum-fed kittens for the first 4 weeks of life. The serum IgA concentrations in both colostrum-deprived groups were significantly lower than colostrum-fed kittens on day 2 after parturition, but were similar thereafter. Colostrum-deprived kittens fostered onto queens in the milk phase of lactation had failure of passive transfer of maternal antibodies. Protective concentrations of immunoglobulins can be restored in kittens with failure of passive transfer of immunity by parenteral administration of adult cat serum, but not by fostering on queens in mid-lactation.

Feline Neonatal Isoerythrolysis and the Importance of Feline Blood Types

“…Although previous studies show that milk immunoglobulin concentration in queens is similar to that present in colostrum [6, 7], nowadays we know that cats have both colostral and milk phases of lactation distinguished by the concentration of IgG and IgA [48]. In cats, IgG and IgA colostrum concentration is greater than that in serum, but reduced concentrations of IgG and IgA have been demonstrated in milk relative to colostrum [48]. IgM concentrations are lower in colostrum and milk than in the queens' serum [6, 7].…”

“…Although transplacentary immunoglobulin transfer is more efficient for IgG [40], fostering on queens in mid-lactation does not provide protective concentrations of immunoglobulins in colostrum deprived kittens [48]. A previous study also shows that parenteral administration of 150 mL/Kg of adult feline serum results in a normal concentration of IgG in colostrum deprived kittens.…”

Vaccination against Feline Panleukopenia: implications from a field study in kittens

“…Queens can transfer maternal antibodies mainly via colostrum conferring protection against disease during the first weeks of life [8,11]. The individual status of maternal immunity has been reported to differ considerably between kittens and is dependent on various factors such as the volume of colostrum ingested, the quality of the colostrum and the time of nursing [12]. Maternally derived antibodies (MDA) interfere with the development of active immunity after vaccination.…”

Pediatrics

“…Hydration status can be monitored by several methods, but weighing the kitten every 6 to 8 hours on an accurate gram scale is level throughout lactation. 10,40 IgG levels then steadily increase as the kitten's own adaptive immunity develops. 8 The amount of passively acquired immunity is determined by the amount of colostrum ingested, the time of ingestion, and the concentration of immunoglobulins in the colostrum.…”

“…10 Several treatments, such as colostrum replacements, are commercially available for these species. 10 Several treatments, such as colostrum replacements, are commercially available for these species.…”