Colostrum Supplements versus Colostrum Replacements

Colostrum supplements, which typically cost between $9 and $18 USD per dose, are designed to provide exogenous IgG to calves to supplement poor-quality maternal colostrum (colostral IgG < 50 g/L).⁷ Most CSs provide between 25 and 60 g of IgG per dose, which is reconstituted in 1 to 2 L of water. Feeding one dose of a CS will not provide a sufficient mass of IgG to prevent failure of passive transfer (FPT) in young calves, nor will it provide sufficient levels of nutrients necessary for calf survival or optimum growth.^7,8 By comparison, CR products, which typically cost between $25 and $40 USD per dose, are designed to be fed instead of maternal colostrum. They should provide a minimum of 100 g of IgG per dose and should provide sufficient levels of nutrients to the calf. It is recommended that CS or CR products be mixed in water, according to the manufacturer’s label directions, and fed as a separate meal after any natural colostrum has been fed.⁹

Manufacturing

Immunoglobulins in commercial CR and CS products are most often derived from spray-dried bovine colostrum or spray-dried bovine serum. For colostrum-derived CR products, fresh-frozen bovine colostrum is collected from grade A dairies and assembled at a manufacturing plant where it undergoes testing for IgG concentration, pooling, heat treatment, spray drying, and then packaging. The concentrations of most non-Ig colostral components (e.g., nutrients, hormones, growth factors), with the exception of cellular fractions (i.e., leukocytes, bacteria), will be similar in colostrum-derived CR products compared with maternal colostrum. For serum-derived CR or CS products, blood is collected from abattoirs under USDA inspection, centrifuged to separate plasma and/or serum from red blood cells, ultrafiltered, spray dried to produce a concentrated powder containing approximately 20% Ig, and then mixed with other ingredients (e.g., lactose, dry fat blend, dextrose, vitamin/mineral premix). The final product may be irradiated. Exact manufacturing methods will vary among manufacturers and products.

Is the Colostrum Replacer or Colostrum Supplement Licensed?

In Canada, it is required that all CR products are licensed through the Canadian Food Inspection Agency (CFIA) Center for Veterinary Biologics (CVB, Ottawa, Ontario, Canada).¹⁰

Serum- or plasma-derived CR or CS products are not permitted in Canada. In the United States, only some manufacturers have acquired a license through the U.S. Department of Agriculture (USDA) Center for Veterinary Biological Products (CVB, Ames, IA). To attain a CVB license and label for prevention or treatment of FPT of Ig, the IgG in U.S. CR products must come from bovine colostrum collected from grade A dairies, must be processed by heat treatment or ionizing radiation using accepted protocols, and must undergo regular purity, potency, and efficacy testing.^11,12 Purity requirements allow a specified total bacteria count. However, coliforms, Salmonella spp., and fungi may not be present. Potency tests require a minimum IgG content for FPT products as determined by a validated radial immunodiffusion (RID) kit or assay. Efficacy testing for FPT products requires that, in 90% of animals, the increase in IgG concentration (pretreatment vs. 24-hour posttreatment) must be at least equal to concentration of the IgG Species Standard approved by the USDA’s Animal and Plant Health Inspection Service (APHIS) (e.g., ≥10 mg/mL serum IgG for neonatal calves) (USDA: 9CFR 113.450; 9CFR 113.499).¹¹ Samples of product from every serial release (batch) are submitted to a central CFIA or USDA laboratory for testing. Also, the overseeing regulatory body completes annual site inspections to review processes and records. As such, licensed products can guarantee safety, potency, efficacy, and traceability. Table 21-1 (Section A) lists CVB-licensed products currently available in Canada and the United States.

Although products that do not have a USDA Veterinary Biologics license are not legally able to claim to supply IgG or to purport to be used as either CS or CR for prevention of FPT, their use for this purpose is widespread in the United States. The Ig in nonlicensed products is technically not considered a feed but is being used in feeds. As such, these products fall under Association of American Feed Control Officials (AAFCO) guidelines (www.aafco.org). Under AAFCO guidelines, every state (i.e., local State Department of Agriculture) adopts and regulates its own animal feed per its applicable laws and regulations. Feed testing programs are in place and regulated in Canada. In the United States, there is a system to identify feed products, but there currently is no system to regulate them through the USDA, FDA, or the State Departments of Agriculture. Although all U.S. manufacturers of non-CVB licensed CR and CS products will conduct some kind of internal quality control testing, these programs are at the manufacturer’s discretion. External product testing or plant inspections by regulatory authorities (e.g., State Department of Agriculture) are not typically completed for non-CVB licensed products unless a problem or complaint is brought to their attention. Table 21-1 (Sections B and C) lists some of the many non-CVB licensed CR and CS products available in the United States.

Evaluating the Efficacy of Colostrum Replacement Products

Producers are strongly encouraged to select CR or CS products that have undergone independent evaluation of efficacy in controlled field studies. Evaluating efficacy should ideally consider passive transfer of adequate IgG, nutritional support, and calf health and performance. Passive transfer of IgG will be primarily determined by the dose of IgG (in grams) administered as well as the efficiency of absorption of IgG. Each product must be independently evaluated, since differences in manufacturing processes can have a significant impact on both apparent efficiency of absorption percentage (AEA %) and final dose of IgG in a package.^13,14 Head-to-head studies are necessary to make valid comparisons among products. Table 21-2 presents the results of field efficacy studies for commercially available CR and CS products that were mixed and fed according to label directions.

Apparent Efficiency of Absorption (AEA %) of Igg.

Grams are more important than percentages; under most circumstances, the total dose (g) of IgG fed will be the most important predictor of APT in calves fed CR products. That said, simply examining the mass of IgG provided by the CR is not an adequate predictor of product efficacy.¹⁹ There can be significant differences in AEA % among products resulting from, but not limited to, such factors as manufacturing methods and quantity, the type of other nutrients or additives, and the age (in hours) at which the calves were fed. The apparent efficiency of absorption (AEA %) is the percentage of IgG administered that is absorbed systemically.¹³ To calculate AEA %, one needs to know the serum IgG (mg/mL is equal to g/L), the grams of IgG originally fed (estimated from testing the maternal colostrum or indicated on the label of the CR or CS fed), and the weight of the calf (in kilograms) from which the plasma volume is estimated (e.g., plasma volume in liters = 9.1% of body weight in kg). The serum IgG (g/L) is multiplied by the plasma volume (L) to calculate the total grams of IgG in the blood. This is then divided by the total grams of IgG fed, and then multiplied by 100 to express efficiency as a percentage. For example, a 43-kg calf has an estimated 3.9 L of plasma (43 kg × 0.091). If the serum IgG concentration of the calf is 10 g/L (10 mg/mL), then the calf has 39 g of IgG in the blood (10 g/L × 3.9 L). If that calf was originally fed 100 g of IgG from maternal colostrum or a CR product, then the AEA would be 39% (39 g/100 g × 100%). Controlled field studies using commercially available CR or CS products, mixed and fed according to label directions, have reported widely varying AEA % values (see Table 21-2). The AEA % reported for CS products has ranged from 16% to 28%.^20,21 The AEA % reported for CR products has ranged from 14% to 51%.^18,22–29 By way of comparison, the AEA % of IgG reported for calves fed 3 to 4 L of fresh maternal colostrum within 6 hours of birth has ranged from 21% to 36%.^{18,20,21,27,29}

The debate continues over whether the IgG in colostrum- or serum-based CR or CS products is more efficiently absorbed. However, relatively few head-to-head field trials exist to investigate this question. In one early CS study in which calves were fed two doses of a colostrum-derived CS (50 g IgG), two doses of either 60 g or 90 g IgG of serum-derived CS, or 3.8 L of maternal colostrum, the AEA % reported for the colostrum-derived CS (16%) was inferior to that of the two serum-derived CS products (24% or 28%) and to maternal colostrum (22%) (see Table 21-2).²⁰ However, because all three CS products delivered an insufficient dose of IgG as compared with maternal colostrum, all three CS products failed to provide APT to calves. Thus far, only two head-to-head controlled field studies have compared the AEA % of commercially available serum- versus colostrum-derived CR products. In one study calves fed 150 g of a lacteal-derived CR had significantly improved AEA % and serum IgG concentrations (AEA = 38.2%; IgG = 14.7 mg/mL) as compared with calves fed 130 g of a serum-derived CR (AEA = 28.4%; IgG = 9.6 mg/mL) (see Table 21-2).²⁶ In this study the improved final serum IgG values for the colostrum-derived CR group were attributed both to increased dose fed (in grams) and improved AEA %. In another recent study, calves fed 150 g of a serum-derived CR had inferior AEA % (21.6%) compared with calves fed 100 g of a colostrum-derived CR (38.8%).³⁰

Only gold members can continue reading. Log In or Register to continue

Share this:

• Click to share on Twitter (Opens in new window)
• Click to share on Facebook (Opens in new window)

Related

Related posts:

1. Collapse and Sudden Death
2. Alterations in Urinary Function
3. Genetic Disorders
4. Biosecurity and Infection Control for Large Animal Practices

Stay updated, free articles. Join our Telegram channel

Join