Waste milk feeding to calves: Are there detrimental effects?
Is waste milk okay for calves or might it have detrimental effects on calves?
By Al Kertz, PhD, PAS, DIPL ACAN
Feeding waste milk to dairy calves has been in vogue for over 20 years (Kesler 1981). I have reviewed various studies in this area (Kertz 2002, 2006, 2011) which have addressed an economic evaluation (Jamaluddin et al.,1996), fed as a liquid instead of milk replacer (Godden et al., 2005), and an evaluation of pasteurization on Pennsylvania dairy farms (Elizondo-Salazar et al., 2020) although I did not cover this in my book (Kertz 2019) but in this article (Kertz 2023). Additionally, there is an on-farm sampling and analysis of pasteurized waste milk which shows its wide nutritional variation (Jorgensen et al., 2006). One nagging issue is whether antibiotic treatment of mastitic or other cows (Selim and Cullor 1997) has any detrimental effects on calves fed that milk source. That is what a comprehensive study in Brazil was designed to determine (Diniz Neto et al., 2024).
Sixty-three male Holstein × Gyr crossbred dairy calves were separated from their dams and within the first 6 hours of life were provided with colostrum equivalent to 10% of their body weight, with a Brix concentration of 25%. During the initial 3 days, calves were housed in individual suspended cages with hay bedding and fed with 6 L per day of transition milk from their dams. Water was provided ad libitum from the first day. Total serum protein concentrations were 6.63, 6.63, and 6.58 g/dL and initial body weight 82.3, 81.5, and 81.7 lb for calves in the bulk tank milk (BTM), waste milk (WM), and pasteurized waste milk (PWM) treatment groups, respectively.
“Calves were randomly assigned to 1 of 3 treatments as noted above. The WM was sourced from cows that had undergone antimicrobial treatments, including those treated for clinical mastitis, placental retention, metritis, or foot infections, across 3 experimental herds within the same research center. Each cow receiving antimicrobial treatment was individually identified and milked separately. Following milking, the milk from those cows was promptly transported to the calf experimental center for utilization. The WM was divided into 2 streams: one intended to be fed directly to animals in the WM treatment group, and the other to undergo pasteurization before being fed to the animals in the PWM treatment group.”
“Following the pasteurization process, a milk sample was assessed for pasteurization efficiency by investigating peroxidase and phosphatase enzymes, and it was only used after confirming the absence of phosphatase and the presence of peroxidase. Calves in the PWM treatment had their first meal immediately after pasteurization (milk temperature of 38°C). The remaining milk was refrigerated for 6 hours (4°C) until the second meal. Milk samples from all 3 treatments were collected immediately before meal feeding to assess somatic cell count (SCC) and total bacterial count (TBC). No significant bacterial differences were observed between preweaning milk fed in the first and second meal.”
“The study included 2 periods: period 1, comprising 18 animals (n = 6/treatment), assessed over 4 to 30 days; and period 2, consisting of 45 animals (n = 15/treatment), underwent evaluation for an extended duration of 4 to 60 days. During the experimental period, animals were housed in individual sand-bedded pens (1.25 × 1.75 m, tethered with 1.2 m long chains). The pens were separated by masonry plates to prevent cross-contamination between animals in different treatments, and each treatment had its dedicated utensils. In all experimental periods, calves received 6 L/day of milk, divided into 2 meals in calf milk feeders…..To maintain consistency in the liquid diet of the calves throughout the experimental periods, meal times were precisely defined and adhered to. A solid diet (calf starter—CS) was offered ad libitum from the fourth day of age. The diet consisted of ground corn, soybean meal, and mineral and vitamin supplements (Table 1).
Pasteurized waste milk had lower dry matter (DM), fat, and lactose than waste milk (WM) or bulk tank milk (BTM).
But protein (CP) was lower for BTM than either WM or PWM, and ash was lowest for BTM
Somatic cell counts (SCC) were lowest on BTM as expected, and intermediate but greater than BTM for PWM while less than WM
Total bacteria count (TBC) had the same pattern as SCC
In addition to calf performance data, digestibility and body component data were also collected (details in the paper).
Apparent total-tract digestibility was measured during 2 periods: from 25 to 29 days of age (n = 6/ treatment) and from 53 to 57 days of age (n = 15/treatment) for 4 consecutive days during each period.
The animals were randomly selected to be slaughtered at 30 ± 1 d (n = 6/treatment) and 60 ± 1 d (n = 15/treatment) for organ weighing and collection of samples for histological development evaluation.
The rumen and cecum were promptly isolated upon opening the abdominal cavity. After isolating the organs, a sample of the contents of the rumen and cecum were collected (50 mL).
Immediately after slaughter, samples were collected for histological comparison from various sections of the dorsal sac and ventral sac of the rumen, omasum, abomasum, and portions of the small intestine including the duodenum, jejunum, and ileum.
Fecal samples were assayed for antimicrobial susceptibility by direct collection from the rectal ampulla from 45 calves (15 per treatment) at 1, 30, and 60 days of age.
Total dry matter intake (DMI) and calf starter (CS) intake did not differ among treatments and within periods.
But milk intake was lowest (P < 0.01) for pasteurized waste milk (PWM) intake than for the other two treatments. However, the biological effect of this is minimal.
Calf starter intake was low across treatments and periods because this was a poor quality meal-form starter.
Because of low CS intake, average daily gains (ADG) were low across treatments and periods; and exhibited lower EE and GE digestibility values. The lower digestibility of EE and GE observed in the PWM treatment in period 2 (4–60 d) can be attributed to the effects of thermal processing on milk fat content and fatty acid composition. In PWM, fat content tends\ed to decrease due to the fat adherence to the container surface after processing (Pestana et al., 2015). Additionally, thermal processing may lead to oxidative losses of unsaturated lipids such as linoleic (C18:2 n-6) and arachidonic acid (C20:4 n-6), as well as certain SFA, such as butyric acid (C4:0), caproic acid (C6:0), and caprylic acid (C8:0; Fidler et al., 201; Pestana et al., 2015)
For other measurements:
Digestibilities among treatments and within periods were not different except for lower organic matter, ether extract, and digestible energy for the PWM treatment versus the other two treatments for the 60 day period.
Nitrogen balance differed only for the 60-day measurements in that it was greater for PWM versus BTM and had greater retention for both WM and PWM versus BTM,
Empty body weight components differed only in larger liver for both waste milk treatment versus bulk tank milk; and for perirenal and omental fat being less for PMW versus the two other treatments.
Ruminal measurements differed only for the 60-day period in that pH was lowest for PWM versus WM and BTM; and acetic VFA was greater for PWM than BTM and WM intermediate. This seems contradictory.
There were no differences among gastrointestinal measurements.
Both WM and PWM had fecal-resistant E. coli suggesting some microbial resistance from either waste milk source.
Caveats:
A poor quality meal CS limited intake and daily gain of calves in this study.
Feeding waste milk seems like a good way to using something which otherwise would be discarded. But it is inconsistent in composition and amount available. And calves, like human babies, like consistency.
Quite a few years ago one animal scientist told me that feeding waste milk to calves was probably the most indefensible practice on a dairy in the eyes of the general public.
I once was early tor an appointment on a large well-operated dairy. While waiting in the conference room, I noted on the whiteboard a series of data which included SCC. They were all well below 100,000. When the manager came and I noted these low SCC. He said to the effect that: yes they were low and he wanted them to stay low because then he had more milk to sell, had less waste milk, and bought milk replacer instead!
The Bottom Line
Waste milk fed to calves should at least be pasteurized. But even that does not eliminate antibiotics in the milk which may then induce antibiotic resistant pathogens when fed to calves. This study found some negative effects for waste milk when fed to calves after being pasteurized, And this study did not measure effects beyond 2 months of age.
References
Diniz Neto, H.C., S. G. Coelho, J. P. Campolina, S. F. Vieira, M. C. Lombardi, B. P. Pereira, B. S. F. Albuquerque, S. F. Costa,4 A. S. Guimarães,, M. A. V. P. Brito, C. S. Silva, F. S. Machado, T. R. Tomich, and M. M. Campos. 2024. Effects of bulk tank milk, waste milk, and pasteurized waste milk on the nutrient utilization, gastrointestinal tract development, and antimicrobial resistance to Escherichia coli in preweaning dairy calves. J. Dairy Sci. 107:6852–6865.
Elizondo-Salazar, J.A., C. Jones and A. J. Heinrichs. 2010. Evaluation of calf milk pasteurization systems on 6 Pennsylvania dairy farms. J. Dairy Sci. 93:5509-5513.
Fidler, N., T.U. Sauerwald, H. Demmelmair, and B. Koletzke. 2001 Fat content and fatty acid composition of fresh, pasteurized, or sterilized human milk. Adv. Exp. Med. Biol. 501:485-495.
Godden, S.M., J.P. Fetrow, J.M. Feirtag, L.R. Green and S.J. Wells. 2005. Economic analysis of feeding pasteurized non-saleable milk versus conventional milk replacer to dairy calves. J. Am. Vet. Med. Assn. 226:1-8 (May 1).
Jamaluddin, A. A., T. E. Carpenter, D.W. Hird, and M.C. Thurmond. 1996
Economics of feeding pasteurized colostrum and pasteurized waste milk to dairy calves. J. Am. Vet. Med. Assoc. 209:751-756.
Jorgensen, M.A., P.C. Hoffman, and A. J. Nytes, 2006. Case study: a field survey of on-farm milk pasteurization efficacy. Prof. Anim, Sci. 22:472-476.
Kertz, A. F. 2002. Feeding calves waste/mastitic milk leads to serious questions. Feedstuffs, July 8, p. 10 and 13.
Kertz, A. F. 2006. Feeding waste milk common despite data. Feedstuffs, July 10, p. 12-13.
Kertz, A. F. 2011, Pasteurized waste milk study reported. Feedstuffs, March 14, p. 12.
Kertz. Alois F. Dairy Calf and Heifer Feeding and Management—Some Key Concepts and Practices. Outskirts Press, July 31, 2019, 166 pages. https://outskirtspress.com/dairycalfandheiferfeedingandmanagement
Kertz, A. F. 2023. PERSPECTIVE AND COMMENTARY: Dairy calf feeding and nutrition major variables and subsequent performance. Appl. Anim. Sci. 39:449-455.
Kesler, E. M. 1981. Feeding mastitic milk to calves: a review. J. Dairy Sci. 64:719-723.
Pestana, J. M., A. Gennari, B.W. Monteiro, D. N. Lehn, and C. F. V. Souza. 2015.
Effects of pasteurization and ultra-high temperature processes on proximate composition and fatty acid profile in bovine milk. Am. J. Food Technol. 10:265-272.
Selim, S.A. and J. S. Cullor. 1997. Number of viable bacteria and presumptive antibiotic residues in milk fed to calves on commercial dairies. J. Am. Vet. Med. Assoc. 211:1029-1035.
BONUS COVERAGEFeeding of bulk tank milk safe for dairy calves?
The feeding of waste milk to dairy calves has been in vogue for more than 20 years but the nagging issue is wither antibiotic treatment of mastitic or other cows has any detrimental effects on calves fed that milk source. Dr. Al Kertz joins us to review a comprehensive look at the subject.View our interview
