|
|
||||||||


* Department of Animal and Nutritional Sciences, Ritzman Laboratory, University of New Hampshire, Durham 03824
ImmuCell Corporation, Portland, ME 04103
Blue Seal Feeds, Londonderry, NH 03053
Corresponding author:
P. S. Erickson; e-mail:
peter.erickson{at}unh.edu.
| ABSTRACT |
|---|
|
|
|---|
Key Words: calves health lactoferrin weaning
Abbreviation key: ADG = average daily gain, LF = lactoferrin
| INTRODUCTION |
|---|
|
|
|---|
Diarrhea is the most common ailment in young calves causing more than 52% of preweaning deaths (NAHMS, 1993). Diarrhea can be caused by a variety of bacteria or viruses, but the most common pathogens are enterotoxigenic Escherichia coli, rotavirus, coronavirus, Cryptosporidium, and Salmonellae (Tromp, 1990). Studies have shown that LF has activity against at least two of these pathogens, E. coli (Teraguchi et al., 1994) and rotavirus (Superti et al., 1997). These data suggest that LF may prevent infection by these organisms in the calf. Evidence has shown that LF has bacteriostatic activity in vivo. Orally administered bovine LF suppresses the proliferation of intestinal E. coli in milk-fed mice (Teraguchi et al., 1994). If similar activity is observed in the gastrointestinal tract of young calves, there is potential for using LF as a preventative supplement to reduce the occurrence of disease or as a treatment for neonatal diarrhea.
Because bovine colostrum and milk contain a low LF concentration, supplementing the diets of preweaned calves with LF could improve their health and overall performance. Results from a recent study conducted in our laboratory demonstrated that calves fed 1 and 10 g/d of LF during the preweaning period weighed more, had increased ADG, tended to consume more dry feed, and tended to have increased feed efficiency (gain/DMI; Joslin et al., 2002). Calves fed 1 g/d of LF had a greater preweaning ADG than calves fed 10 g/d LF.
The objective of the present study was to further examine the effects of supplemental LF on calf health, growth, feed intake, and feed efficiency.
| MATERIALS AND METHODS |
|---|
|
|
|---|
At birth, 40 Holstein calves (36 heifers and four bulls) were randomly assigned by blocks of four, to one of four treatments: 0 (control), 1, 2, or 3 g/d of LF. The iron saturation of the LF (Agri-Cell, Methuen, MA) was 13.2 mg/100 g. All calves received 2 L of good quality colostrum, tested by a colostrometer, within 3 h after birth, and another 2 L of good quality colostrum 8 to 12 h later. Calves were removed from their dam before the first colostrum feeding and placed in a naturally ventilated, enclosed calf room, in individual pens. Pens were bedded with kiln-dried sawdust. The calves remained in their pens for the duration of the study. On the day of birth, an initial BW was obtained before the second feeding of colostrum. On d 2, calves were fed a nonmedicated, all-milk protein milk replacer (Dairy Maid, Blue Seal Feeds, Londonderry, NH) in two feedings at 0700 and 1500 h. Beginning on d 2, every day each calf received 1.2% of its initial BW, in milk replacer powder. The milk replacer powder was divided into two equal portions, and each portion was reconstituted in 2 L of warm water immediately before feeding. Starting on d 3, and continuing until 14 d postweaning, calves had unlimited access to a nonmedicated starter (Calf Starter, Blue Seal Feeds) and fresh water. Starting on d 3, LF treatment was mixed with milk replacer and divided equally among the two feedings. Fresh starter and milk replacer were given to calves twice daily. Starter orts were collected and weighed daily. The starter consisted of steam-flaked corn, crimped oats, molasses, and pellets. Calves were weaned abruptly when they met the following four criteria: 1) minimum of 21 d old, 2) daily starter DMI was
1% of initial BW, for three consecutive days, 3) cumulative starter DMI was
9% of initial BW, and 4) weight gain was
12% of initial BW (Greenwood et al., 1997). Calves were removed from the study at 14 d postweaning.
Feed Intake and Feed Analysis
Feed intake was calculated on a daily basis. The DM of the orts was determined daily, and the DM of the starter and milk replacer powder was determined for each 22.7-kg bag. The DM of the milk replacer powder, starter, and orts was determined by drying samples in a forced-air convection oven (VWR Scientific Products Corp., Boston, MA) at 60°C for 24 h. Samples of starter and milk replacer powder were saved from each bag of feed and stored at -20°C. When the study was completed, samples were composited by shipment (20 bags/shipment of starter, and 10 bags/shipment of milk replacer) for nutrient analysis. Composited starter samples were dried in the forced-air convection oven at 60°C for 6 h and ground through a 1-mm screen using a Wiley mill (Thomas Scientific, Swedesboro, NJ). Milk replacer and starter were analyzed for CP (AOAC, 1979), fat, or fatty acid content (AOAC, 1995), and Ca, P, Mg, and Fe (AOAC, 1990). Starter was also analyzed for NDF (Goering and Van Soest, 1970). Water was tested for iron levels by atomic absorption (Clesceri et al., 1989). Milk replacer was reconstituted to 12.2% DM for determination of LF levels using ELISA (Bethyl Laboratories, Inc., Montgomery, TX).
Measurements
Calves were weighed and measured for heart girth once per week. Calves born on Friday through Monday were weighed and measured every Monday, and calves born on Tuesday through Thursday were weighed and measured every Thursday. Calves were also weighed at birth, weaning, and 14 d postweaning. Evaluation of fecal consistency was performed by three independent scorers every Monday, Wednesday, and Friday. Two of the three scorers were blind to treatment. Feces were scored on a scale of 1 to 4, with 1 = firm and 4 = watery diarrhea. Sick days were recorded as any day that a calf received medication. Medication was given to calves that had a fecal score greater than or equal to 3 (antibiotic and electrolyte treatment), or calves that had a rectal temperature greater than 39°C.
Statistical Analysis
A randomized, complete block design was used, and calves were randomly assigned to treatments in blocks of four. Analysis of variance was conducted using the MIXED procedure of SAS (SAS release 8.2, 2001). The mixed effects model used was:
![]() |
where
| Yijk | = | is the dependent variable,
|
| µ | = | is the overall mean,
|
| bi | = | is the random effect of block i (i = 1, ...10),
|
| Lj | = | is the fixed effect of the jth lactoferrin level (j = 0, ...3),
|
| K | = | is the regression coefficient of the covariate C,
|
| Cijk | = | is the value of the covariate variable for the kth calf, of the ith block, of the jth lactoferrin level (k = 1, ...4), and
|
| eijk | = | is the random error associated with the calf k, in block i, that received lactoferrin level j.
|
Initial BW was used as a covariate for all measures. Significance was determined at a probability value
0.05. Data were tested for linear, quadratic, and cubic responses to level of LF supplementation. The data from one calf, on the 2-g treatment, were removed from the statistical analysis, due to abnormal eating habits and severe illness.
| RESULTS |
|---|
|
|
|---|
|
|
|
|
|
Preweaning feed efficiency (gain/DMI) increased linearly with increasing LF supplementation, whereas postweaning feed efficiency decreased linearly (Table 3
). Similar to ADG, wk-5 feed efficiency tended (P = 0.07) to respond quadratically, with the 0-g and 3-g treatments having higher feed efficiency than the 1-g and 2-g treatments. Overall, average daily heart girth gain increased linearly (P = 0.02) with LF level (0.25, 0.24, 0.29, 0.31 cm/d; SE = 0.02) for treatments 0, 1, 2, and 3 g/d.
| DISCUSSION |
|---|
|
|
|---|
Diarrhea is a major problem in young calves, especially during the preweaning period. In the present study, preweaning fecal scores were the lowest for the calves fed 1 g/d LF and the highest for the control calves. Preweaning and total number of days medicated followed a similar response pattern. It has been demonstrated that LF has bacteriostatic and bactericidal properties that are effective against pathogenic bacteria such as E. coli (Dionysius et al., 1993; Teraguchi et al., 1994). More specifically, calves treated with a preparation containing LF and the lactoperoxidase system were able to survive a lethal intestinal infection of enterotoxigenic E. coli (Still et al., 1990). With E. coli being the principle pathogen responsible for neonatal calf diarrhea, supplemental LF may have reduced the establishment of E. coli in the gut of the calf, leading to reduced bouts of diarrhea. Similarly, LF has been shown to be effective against the diarrhea-causing pathogen, rotavirus (Superti et al., 1997). If calves in this study were exposed to rotavirus, then LF may have played a role in reducing the occurrence of infection by this virus.
From the results of this study, it appears that of the doses given, 1 g/d LF was the optimal dose for reducing disease. This finding is consistent with previous results from our laboratory, where calves fed 1 g/d of LF had lower numbers of days medicated than calves fed 0 or 10 g/d of LF (Joslin et al. 2002). However, in the previous study, this result was not significant, probably due to a small sample size. The results of these two studies make it apparent that the higher doses of LF are not as effective at reducing disease. Supplementing the milk replacer with 1 g/d of LF brought the total concentration of LF in the milk replacer to a concentration similar to that found in average bovine whole milk (250 mg/ml). The intestinal system of the newborn calf may be best adapted to utilizing this low level of LF to optimize health. Adding LF to milk replacer may be a way to make it more similar to milk, which may benefit the health of calves. It is clear from the results of this study that 1 g/d of supplemental LF improves health during the preweaning period. It should be noted here that the calves in this study were well-managed and generally healthy. The fact that LF improved the health of calves in a high-quality environment suggests that where conditions are less desirable, LF may be even more effective at improving health.
While LF supplementation resulted in health responses, it also resulted in growth and feed efficiency responses. During the preweaning period, when the calves were receiving treatments, ADG and gain/DMI increased linearly as the level of supplemental LF increased. Intake of DM was not affected by LF supplementation. These results are similar to those of our previous study except that they found that calves fed the 1-g treatment had higher ADG and gain/DMI than calves fed the 10-g treatment (Joslin et al., 2002). This suggests that the linear effect of LF supplementation on ADG and gain/DMI does not continue up to 10 g/d.
It cannot be determined from this study whether the growth and feed efficiency responses to LF supplementation are indirect effects of improved health or direct effects on increased nutrient absorption. Lactoferrin is known to act as a growth factor by stimulating mucosal growth of the small intestine in vivo. Zhang et al. (2001) observed that the small intestine weight of rat pups consuming milk containing 12 mg/ml of human LF increased 27%, and intestinal length increased by 6.5% compared with rat pups consuming milk containing no human LF. In the present study, it is possible that the supplemental LF was acting as a growth factor in the small intestine of the calf. A more developed intestinal mucosa will have greater absorptive ability, allowing the calf to absorb more nutrients. Therefore, calves that received supplemental LF may have been able to absorb more nutrients from their feed and may have been more efficient at converting feed into BW gain.
During the postweaning period, after calves had stopped receiving supplemental LF, gain/DMI decreased linearly with increased feeding of LF during the preweaning period (Table 3
). Our previous study did not show this postweaning effect. In spite of the decreased feed efficiency, postweaning ADG was not different among treatments. More research is needed to determine how LF is affecting feed efficiency, both preweaning and postweaning.
Over the entire experimental period, average daily heart girth gain increased linearly with increased LF supplementation. Increased hearth girth gains were probably due to increased skeletal growth. Perhaps the increased feed efficiency during the preweaning period allowed the LF-supplemented calves to grow more than the control calves.
It seems that supplemental LF improves the growth rates and health of preweaned calves. More research should be performed to further understand the mode of action of LF and its improvement in growth rates of calves. Due to the reduced occurrences of diarrhea, providing young calves with supplemental LF could be economically beneficial to the dairy producer, because of reduced costs for medication and labor. The reduced occurrence of diarrhea, seen in the preweaned calf, supplemented with 1 g/d of LF, is supported by the differences seen in wk 2 for fecal scores and wk 2 and 3 for number of days medicated. Based on these results, it may be beneficial for dairy producers to feed 1 g/d of LF to calves for the first 21 d of life.
Using LF as a preventative supplement or as a treatment for diarrhea could reduce the use of traditional antibiotics. Due to the ever-increasing prevalence of antibiotic-resistant strains of bacteria, LF may play an important role in future medicine. Several recent studies have shown that LF is effective against antibiotic resistant bacteria and that it is able to reduce the resistance of some bacteria to antibiotics (Aguila et al., 2001; Leitch and Willcox, 2001). Lactoferrin could be used as a replacement for traditional antibiotics, or it could be used adjunctively with antibiotics to treat antibiotic-resistant bacteria.
| CONCLUSIONS |
|---|
|
|
|---|
| ACKNOWLEDGEMENTS |
|---|
|
|
|---|
| FOOTNOTES |
|---|
2 Support for this project was through the New Hampshire Agricultural Experiment Station H-395, and gifts from ImmuCell Corporation, Portland, ME, and Blue Seal Feeds, Londonderry, NH. ![]()
Received for publication July 11, 2002. Accepted for publication September 30, 2002.
| REFERENCES |
|---|
|
|
|---|
This article has been cited by other articles:
![]() |
E. A. English, B. A. Hopkins, J. S. Stroud, S. Davidson, G. Smith, C. Brownie, and L. W. Whitlow Lactoferrin Supplementation to Holstein Calves During the Preweaning and Postweaning Phases J Dairy Sci, November 1, 2007; 90(11): 5276 - 5281. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. I. Kehoe, B. M. Jayarao, and A. J. Heinrichs A Survey of Bovine Colostrum Composition and Colostrum Management Practices on Pennsylvania Dairy Farms J Dairy Sci, September 1, 2007; 90(9): 4108 - 4116. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. E. Cowles, R. A. White, N. L. Whitehouse, and P. S. Erickson Growth Characteristics of Calves Fed an Intensified Milk Replacer Regimen with Additional Lactoferrin J Dairy Sci, December 1, 2006; 89(12): 4835 - 4845. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Rufibach, N. Stefanoni, V. Rey-Roethlisberger, P. Schneiter, M. G. Doherr, L. Tappy, and J. W. Blum Protein synthesis in jejunum and liver of neonatal calves fed vitamin A and lactoferrin. J Dairy Sci, August 1, 2006; 89(8): 3075 - 3086. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |