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J. Dairy Sci. 2008. 91:3716-3722. doi:10.3168/jds.2008-1094
© 2008 American Dairy Science Association ®
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Crossbreds of Jersey x Holstein Compared with Pure Holsteins for Body Weight, Body Condition Score, Dry Matter Intake, and Feed Efficiency During the First One Hundred Fifty Days of First Lactation

B. J. Heins1, L. B. Hansen, A. J. Seykora, A. R. Hazel, D. G. Johnson and J. G. Linn

Department of Animal Science, University of Minnesota, St. Paul 55108

1 Corresponding author: hein0106{at}umn.edu


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS
 ACKNOWLEDGEMENTS
 REFERENCES
 
Jersey x Holstein crossbred (JxH) cows (n = 24) were compared with pure Holstein cows (n = 17) for body weight, body condition score, dry matter intake (DMI), and feed efficiency during the first 150 d of first lactation. Cows were housed in the University of Minnesota dairy facility at the St. Paul campus and calved from September 2004 to January 2005. The JxH cows were mated by artificial insemination with Montbeliarde bulls, and Holstein cows were mated by artificial insemination with Holstein bulls. Cows were weighed and body condition was scored every other week. Cows were individually fed a TMR twice daily, and feed refusals were measured once daily. The DMI of cows was measured daily and averaged across 7-d periods. Milk production and milk composition were from monthly Dairy Herd Improvement records. Best Prediction was used to calculate actual production (milk, fat, protein) for each cow from the 4th to 150th day of first lactation. The JxH cows had significantly less body weight (467 vs. 500 kg) and significantly higher body condition scores (2.90 vs. 2.76) than pure Holstein cows. The JxH cows had significantly less milk production (4,388 vs. 4,644 kg) during the 4th to 150th day of lactation than did pure Holstein cows. However, fat plus protein production during the first 150 d of lactation was not significantly different for JxH (302 kg) and Holstein (309 kg) cows. The JxH and pure Holstein cows did not differ significantly for daily DMI (22.0 vs. 22.7 kg, respectively), and the JxH (4.7%) and pure Holstein (4.5%) cows consumed similar DMI based on percentage of body weight. Consequently, feed efficiency for the 4th to 150th day of lactation did not differ for JxH and pure Holstein cows.

Key Words: crossbreeding • feed efficiency • body condition score • body weight


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS
 ACKNOWLEDGEMENTS
 REFERENCES
 
Crossbreeding of dairy cattle is a topic of growing interest because of dairy producers’ concerns regarding heifer and cow fertility, cow health, and calf survival (Funk, 2006). In a survey by Weigel and Barlass (2003), dairy producers indicated crossbreeding improved the fertility, survival, and profitability of dairy cows.

Recent research has documented the effects of cross-breeding in dairy cattle (Heins et al., 2006a,b,c; Auldist et al., 2007; Dechow et al., 2007; Heins et al., 2008). However, these studies have predominantly focused on production, fertility, and the productive life of cross-bred versus pure Holstein cows. Numerous studies have compared pure Jersey and pure Holstein cows for BW and feed intake (Dickinson et al., 1969; Blake et al., 1986; Rastani et al., 2001); however, very little research has compared crossbred and pure Holstein cows for BW, BCS, feed intake, and feed efficiency (FE).

Touchberry and Batra (1976) reported that Guernsey x Holstein crossbred cows had lower BW than did pure Holstein cows. McDowell and McDaniel (1968) reported that Brown Swiss x Holstein and Ayrshire x Brown Swiss crossbred cows tended to have higher BCS than pure Holstein cows. In Australia, Jersey x Holstein crossbred (JxH) cows had 40 kg less BW than did pure Holstein cows; however, crossbred cows had higher BCS than did pure Holstein cows (Auldist et al., 2007).

McDowell and McDaniel (1968) reported that Ayrshire x Holstein and Brown Swiss x Holstein crossbred cows were generally superior to pure Holstein cows for 3 alternative measures of FE (therms of energy produced/therms of energy consumed, FCM/therms of net energy consumed, and protein production/feed protein intake). In a study at Agriculture Canada, Wang et al. (1992) found that Ayrshire x Holstein crossbred cows had similar FE to pure Holstein cows. In a Swiss study, JxH cows had significantly less net energy intake than pure Holstein cows; however, JxH cows were more feed efficient than pure Holstein cows (Schwager-Suter et al., 2001).

A recent study of a Wisconsin commercial dairy compared the DMI and FE for a pen of JxH and pure Jersey cows and for a pen of pure Holstein cows (Anderson et al., 2007). Mean BW was 93 kg less for the combined JxH and pure Jersey cows than for the pure Holstein cows; however, BCS were similar for the 2 groups. The JxH and pure Jersey cows consumed 2.2 kg less DMI, but they also had lower production of ECM than did the pure Holstein cows. In addition, González-Verdugo et al. (2005) reported that both JxH and pure Holstein cows on pasture consumed similar amounts of DMI.

The objectives of this study were to determine differences between JxH cows and pure Holstein cows during the first 150 d of first lactation for BW, BCS, DMI, and FE in a confinement dairy facility at the University of Minnesota.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS AND DISCUSSION
 CONCLUSIONS
 ACKNOWLEDGEMENTS
 REFERENCES
 
Experimental Design
The dairy facility on the St. Paul campus of the University of Minnesota has 90 tie stalls, and the West Central Research and Outreach Center, Morris, has 150 cows in a low-input grazing environment. These 2 locations shared a study to compare crossbred and pure Holstein cattle. Crossbreeding began in December 2000 with the mating of 50% of the pure Holstein cows and heifers at both locations to Jersey AI bulls and the other 50% to Holstein AI bulls. Heifers and cows at both locations were paired by age and sire, and one member of each pair was randomly assigned to 1 of the 2 breeding groups. Jersey bulls were randomly mated to Holstein heifers and cows, but inbreeding coefficients were not allowed to surpass 6.25% for matings of Holstein heifers and cows with Holstein bulls.

Jersey and Holstein service sires were selected based on high Net Merit within breed, and 3 sires were selected per year from each breed. Both locations breed cattle seasonally; cows at St. Paul calve in the fall, and cows at Morris calve mostly in the spring, with some calving in the fall. All virgin heifers are reared and bred at Morris, which is a low-input environment. The mating design was used for 2 years, and all resulting JxH heifers and cows were mated to Montbeliarde AI bulls, and their pure Holstein contemporaries were mated to Holstein AI bulls.

Data
A subset of cows from the study by Heins et al. (2008) were used for the analysis of BW, BCS, DMI, and FE; however, only cows that calved for the first time at St. Paul were studied. Cows at Morris are not housed in a tie-stall barn; therefore, collection of daily feed intake was not feasible. At St. Paul, 26 JxH and 19 pure Holstein cows calved for the first time from October 2004 to January 2005. Two JxH cows died from calving injury, and 2 pure Holstein cows were culled at 28 and 46 d postpartum because of gangrene mastitis and were removed from the study. Therefore, 24 JxH and 17 pure Holstein cows that calved for the first time at 24.4 (±1.0) mo and 25.1 (±2.1) mo of age, respectively, remained for comparison. Calving difficulty was not significantly different for the 2 breed groups. For both breed groups, 6 AI bulls had daughters represented in the study.

All cows were fed the same TMR, and the ration contained 62.8% DM. The TMR consisted of 14.8% chopped alfalfa hay, 35.0% corn silage, 26.5% protein mix, 15.5% ground corn, 5.2% roasted soybeans, and 3.0% molasses. The protein mix composition was 34.3% soybean meal, 26.7% soybean hulls, 22.9% distillers dried grains with solubles, 12.3% vitamins and minerals, and 3.8% blood meal. The TMR was fed twice daily with a Calan Data Ranger (American Calan, North-wood, NH), and feed refusals were collected once daily. Feed intake and refusals were collected on cows from 4 to 150 d postpartum.

BW and BCS
The BW and BCS were recorded during the evening milking every other week during the first 150 d post-partum. With data spanning 150 d, each cow had BW and BCS recorded 10 times at 14-d intervals (1 to 15 d, 16 to 30 d, 31 to 45 d, etc.). The BW was recorded on individual cows by using a digital scale as cows exited the milking parlor, and the BCS was measured by the same person throughout the study on a 1 to 5 scale, with 1 = excessively thin and 5 = excessively fat, in increments of 0.25 (Wildman et al., 1982).

Independent variables for statistical analysis of BW and BCS were the fixed effects of age at calving, breed group, and 14-d period nested within breed group. The MIXED procedure of SAS (SAS Institute, 2004) was used, with cow nested within breed as a random variable with repeated measures. The autoregressive covariance [AR(1)] structure was used because it resulted in the lowest Akaike’s information criterion (Littell et al., 1998).

Production
Actual milk (kg), fat (kg), and protein (kg) production from twice daily milking during the first 150 d of first lactation was calculated with Best Prediction (BP), which was implemented by the Animal Improvement Programs Laboratory in February 1999 for national genetic evaluation in the United States (VanRaden, 1997). Test-day observations from DHI were used to estimate production for the 4th to 150th day of lactation to be consistent with DMI, which was not recorded for the first 3 d of lactation. The BP adjusted for age at calving and predicted individual daily production from observed test-day production (Cole and VanRaden, 2007).

Standard edits were applied to test-day observations for production and were similar to those used by the USDA for routine genetic evaluation, and are described in Heins et al. (2006c). Each test day had an observation for milk, fat, and protein production. Estimated daily production of milk, fat, and protein for each cow was summed for DIM from the 4th to 150th day of lactation, which resulted in 147-d production records for all cows. In addition, ECM for each cow was calculated (Tyrrell and Reid, 1965), with ECM (kg) = [0.327 x (milk kg)] + [12.96 x (fat kg)] + [7.2 x (protein kg)].

Age at calving and breed group were fixed effects for statistical analysis of milk, fat, protein, fat plus protein, and ECM from the 4th to 150th day postpartum of first lactation. The GLM procedure of SAS (SAS Institute, 2004) was used to obtain solutions and conduct the ANOVA.

DMI and FE
Daily DMI was collected for cows from the 4th to 150th day postpartum. The DMI were averaged for weeks (7-d periods). With data spanning 147 d, each cow had feed intakes recorded for 21 periods (4 to 10 d, 11 to 17 d, 18 to 24 d, etc.).

Fixed effects for the statistical analysis of DMI were age at calving, breed group, and 7-d period nested within breed group, and the MIXED procedure of SAS (SAS Institute, 2004) was used, with cow nested within breed as a random variable with repeated measures. Once again, the autoregressive covariance [AR(1)] structure was used because it resulted in the lowest Akaike’s information criterion (Littell et al., 1998).

Two measures of feed efficiency were used to compare JxH and pure Holstein cows. The FEFP was the ratio of 147-d fat plus protein production (kg) divided by 147-d DMI (kg), and the FEEN was the ratio of 147-d ECM (kg) divided by 147-d DMI (kg). Total DMI was the sum for daily DMI from the 4th to 150th day post-partum for each cow. Age at calving and breed group were fixed effects for statistical analysis of total DMI, FEFP, and FEEN from the 4th to 150th day postpartum of first lactation. The GLM procedure of SAS (SAS Institute, 2004) was used to obtain solutions and conduct the ANOVA.


   RESULTS AND DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
CONCLUSIONS
 ACKNOWLEDGEMENTS
 REFERENCES
 
BW and BCS
Age at calving and 14-d period nested within breed group significantly (P < 0.01) explained variation in BW. The solution for linear regression of age at calving (16.9 ± 3.8) indicated that older cows at calving had greater BW. Least squares means, standard errors of means, and standard deviations for BW for each 14-d period and across the 150 d are given in Table 1Go. Across the 150 d, the JxH cows had 33 kg less BW (P < 0.01) than the pure Holstein cows (467 vs. 500 kg).


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  		Table 1. Least squares means, standard errors of means, and standard deviations for BW (kg) of cows during the first 150 d of first lactation for breed groups
 
Within each 14-d period, JxH cows had significantly less (P < 0.05) BW than pure Holstein cows (Table 1Go). The difference in BW of JxH cows compared with pure Holstein cows ranged from 30 kg for the 4th period to 38 kg for the 7th period. The BW change was similar for JxH versus pure Holstein cows from the beginning to the end of the study (+16.8 vs. +19.7 kg, respectively). The BW decreased slightly at the beginning of lactation for cows and then increased steadily for both JxH and pure Holstein cows through the 10th period.

Results for BW are consistent with the results of Auldist et al. (2007), who reported that JxH cows had 40 kg less BW than did pure Holstein cows. Touchberry and Batra (1976) reported that Guernsey x Holstein crossbred cows had less BW than did pure Holstein cows; moreover, they found that both Guernsey x Holstein crossbred cows and pure Holstein cows decreased in BW early in lactation, but had a steady increase in BW through the first 150 d of lactation.

For BCS, only 14-d period nested within breed significantly (P < 0.01) explained variation. Table 2Go shows least squares means, standard errors of means, and standard deviations for BCS across the 150 d and for each 14-d period. The BCS were relatively low at calving because the first-lactation cows in this study were grown on pasture without energy supplementation for the summer before fall calving. For the mean of the 14-d periods, JxH cows had significantly (P < 0.01) greater BCS than did pure Holstein cows (2.90 vs. 2.76, respectively). Furthermore, JxH cows had significantly (P < 0.05) greater BCS than did pure Holstein cows at periods 1, 2, 3, 4, and 6, with a tendency (P < 0.10) for JxH cows to have higher BCS than pure Holstein cows for periods 5, 7, 8, and 10. The breed groups did not differ for BCS for period 9.


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  		Table 2. Least squares means, standard errors of means, and standard deviations for BCS of cows during the first 150 d of first lactation for breed groups
 
Both JxH and pure Holstein cows decreased in BCS at the beginning of lactation (Table 2Go), which suggests cows were mobilizing body fat to meet the demands of production (Britt et al. 2003). Furthermore, the BCS of JxH cows plateaued earlier than the BCS of pure Holstein cows.

Washburn et al. (2002) reported that pure Jersey cows had greater BCS than did pure Holstein cows (2.96 vs. 2.70); however, Rastani et al. (2001) found no significant differences between pure Jersey and Holstein cows for BCS. In agreement with the present study, Auldist et al. (2007) and Heins et al. (2008) reported that JxH cows had greater BCS than did pure Holstein cows.

Production
Table 3Go gives least squares means, standard errors of means, and standard deviations of JxH and pure Holstein cows for 147-d milk, fat, and protein production, fat plus protein production, FCM, and ECM. Age at calving significantly (P < 0.05) influenced all traits. The JxH cows tended to have significantly (P < 0.10) less 147-d milk volume (4,388 vs. 4,644 kg) than pure Holstein cows. However, JxH cows were not significantly different (P > 0.10) from pure Holstein cows for 147-d fat (170 vs. 172 kg), 147-d protein (132 vs. 137 kg), and 147-d fat plus protein (302 vs. 309 kg) production. Furthermore, JxH cows were similar (P > 0.32) to pure Holstein cows for 147-d ECM (4,590 vs. 4,732 kg). Auldist et al. (2007) found that JxH cows had significantly less milk volume than pure Holstein cows, but breed groups did not differ for fat or protein production. Heins et al. (2008) reported that JxH cows had significantly less 305-d milk (7,147 vs. 7,705 kg), 305-d protein (223 vs. 238 kg), and 305-d fat plus protein (497 vs. 515 kg) production than pure Holstein cows in first lactation; however, breed groups were not significantly different for 305-d fat (274 vs. 277 kg) production.


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  		Table 3. Least squares means, standard errors of means, and standard deviations for milk, fat, and protein production, and ECM of cows from the 4th to 150th day postpartum of first lactation for breed groups
 
DMI and FE
Both age at calving (P < 0.05) and 7-d period nested within breed group (P < 0.01) significantly explained variation in weekly DMI. The solution for linear regression of age at calving (0.48 ± 0.24) for the mean of weekly DMI indicated that older cows at calving had greater DMI. Least squares means, standard errors of means, and standard deviations of weekly DMI for the 4th to 150th day postpartum by breed group are given in Table 4Go. The JxH cows did not differ (P > 0.10) from the pure Holstein cows for DMI during any period postpartum. The DMI rapidly increased for both breed groups from the 1st to 15th period postpartum. For the 15th period, DMI appeared to plateau at 25 to 26 kg/d (Table 4Go). The JxH cows (22.0 kg) did not differ (P > 0.30) from the pure Holstein cows (22.7 kg) for mean weekly DMI, and the JxH and pure Holstein cows consumed similar DMI as a percentage of BW (4.7 vs. 4.5%, respectively). Anderson et al. (2007) had somewhat lower DMI as a percentage of BW, at 4.3 versus 4.0% for JxH and pure Jersey cows and pure Holstein cows, respectively.


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  		Table 4. Least squares means, standard errors of means, and standard deviations for DMI (kg) of cows from the 4th to 150th day postpartum of first lactation for breed groups1
 
Results for the DMI of pure Holstein cows in this study are similar to those reported by Rastani et al. (2001) and Britt et al. (2003), who found that pure Holsteins consumed 22 to 23 kg of DMI daily in early lactation. Lee et al. (1989) reported some heterosis for total digestible nutrients consumed for crossbred Ayrshire and Holstein cows compared with pure Holstein cows.

Table 5Go shows least squares means, standard errors of means, and standard deviations of JxH and pure Holstein cows for total DMI (as opposed to weekly DMI), FEFP, and FEEN from the 4th to 150th day postpartum. Age at calving tended (P < 0.10) to affect only total DMI. The JxH cows (3,233 kg) were not significantly (P > 0.42) different from the pure Holstein cows (3,326 kg) for total DMI from the 4th to 150th day postpartum of first lactation. Furthermore, JxH and pure Holstein cows did not differ (P > 0.88) for FEFP (0.094 vs. 0.093) or FEEN (1.43 vs. 1.43). Therefore, JxH cows produced similar amounts of fat plus protein (kg) and ECM per kilogram of DMI consumed compared with pure Holstein cows. The measures of FE used in this study do not partition energy into the alternative components for production, body maintenance, growth, or restoration of body reserves. The potential for the JxH cows to devote less energy to body maintenance and growth, but more energy to restoration of body reserves, could perhaps account for the enhanced fertility and health of crossbreds in many studies. The results are in agreement with those of Wang et al. (1992), who reported that crossbred cows had FE (milk production/total digestible nutrients) similar to that of pure Holstein cows; however, Schwager-Suter et al. (2001) found that JxH cows had more FE (energy content of milk/net energy intake) than did pure Holstein cows.


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  		Table 5. Least squares means, standard errors of means, and standard deviations for total DMI and 2 measures of feed efficiency from the 4th to 150th day postpartum of first lactation for breed groups
 

   CONCLUSIONS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS
ACKNOWLEDGEMENTS
 REFERENCES
 
Many dairy producers have turned to crossbreeding to reduce calving difficulty and stillbirths of cows and to improve the health, fertility, and productive life of cows. However, dairy producers should consider BW, BCS, DMI, and FE when selecting among alternative dairy breeds for a crossbreeding system.

In this study, JxH cows had 33 kg less BW and greater BCS than did pure Holstein cows during the first 150 d of first lactation. Furthermore, the JxH cows in this study were not different from pure Holstein cows for any measure of production, except for fluid volume and for DMI from the 4th to 150th day postpartum for first lactation. Therefore, JxH cows also had similar FE compared with pure Holstein cows during roughly the first half of lactation.

Some might expect JxH cows to consume less DMI than pure Holstein cows because of their similar production but smaller BW; however, this study suggests the DMI of JxH cows was similar to that of pure Holsteins. Apparently, JxH cows used DMI beyond their needs for production and body maintenance to achieve greater BCS.

The data for this study were recorded in a single herd with a small sample size; therefore, additional research with greater numbers of cows in varied environments is needed to fully compare crossbred vs. pure Holstein cows for BW, BCS, DMI, and FE. In addition, this study investigated only the first 150 d of first lactation, and additional research is needed comparing multiple 305-d lactations of crossbred versus pure Holstein cows for BW, BCS, DMI, and FE. Assessment of total economic merit of JxH versus pure Holstein cows must include BW, BCS, DMI, production, and FE, as well as many other factors such as calving difficulty, stillbirth, fertility, health, survival, and salvage value of cows.


   ACKNOWLEDGEMENTS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS
 ACKNOWLEDGEMENTS
REFERENCES
 
The authors express appreciation to John Cole at USDA-Animal Improvement Programs Laboratory (Beltsville, MD) for the use of the Best Prediction program. The authors also express gratitude to Bill Hansen and coworkers at the St. Paul dairy facility for their assistance in data collection and the care of animals. Funds for this research were provided by the American Jersey Cattle Club Research Foundation (Reynoldsburg, OH).

Received for publication February 12, 2008. Accepted for publication May 21, 2008.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS AND DISCUSSION
 CONCLUSIONS
 ACKNOWLEDGEMENTS
 REFERENCES
 


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