| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
* Department of Animal Science, University of Wyoming, Laramie 82071;
and
Department of Veterinary Science, University of Wyoming, Laramie;
and
Department of Animal and Range Sciences, Montana State University, Bozeman; and
and
Department of Animal and Range Sciences, New Mexico State University, Las Cruces
3 Correspondence:
P.O. Box 3684 (phone: 307-766-5374; fax: 307-766-2355; E-mail:
gm{at}uwyo.edu).
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
0.11). Days to conception did not differ (P = 0.40) among treatments. Although overall productivity of the primiparous cows and their calves was not altered by safflower-seed supplementation, differential effects were noted between supplements. Oleate supplementation increased percentage milk fat at d 60, and cow body condition score was lower than in linoleate-supplemented cows. Linoleate-supplemented cows had greater body condition scores by 90 d postpartum than either corn-soybean- or oleate-supplemented cows.
Key Words: Beef Cows • Fats • Reproduction • Safflower
|
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
Limited information is available regarding responses to lipid supplements derived from a common source with varying fatty acid composition. Therefore, the objective of the current study was to determine if fatty acid composition of supplements fed postpartum influences overall dam and calf performance when cows consumed medium-quality forage. A second goal was to determine if fatty acid content of the postpartum supplement affects serum metabolites, metabolic hormones, and milk production and composition.
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
). Cows were housed in one of six pens with six animals per pen and had ad libitum access to native grass hay (CP = 7.8%, ADF = 46.3%, NDF = 75.7%, total fatty acids = 1.1%, IVDMD = 55.3%) provided in large round bales. Water, trace mineral, and vitamin-fortified salt (NaCl = 12 to 14.4%, Ca = 12 to 14.4%, P 12.0%, Mg 0.06%, K 1.0%, Co 1450 ppm, Zn 5815 ppm, vitamin A 330,693 IU/kg, vitamin B3 33,069 IU/kg) were provided ad libitum. Supplements were individually fed once daily at 0630 for 90 d. Following the 90-d treatment period, all animals were placed in a common group and fed a common diet. Pre-experimental analysis determined that linoleate seeds contained 20.8% CP and 33.9% lipid. Oleate seeds had 16.2% CP and 35.1% lipid. Corn and soybean meal had CP values of 8.9 and 49.6%, respectively. Oilseeds and corn were dry-rolled before the mixing of supplements. Safflower-seed supplements were formulated to provide 5% total DM intake as lipid. Estimates for hay intake and cow performance were based on Alderton et al. (2000). By using estimated hay intake, supplements were formulated to be isonitrogenous and have equal amounts of TDN and meet NRC (1996) nutritional requirements for a 24-mo, 499-kg lactating cow (565 kg mature BW) producing 9.1 kg milk/day during peak lactation. Tabular values for TDN were utilized to formulate supplements (NRC, 1982).
|
A single blood sample was collected on d 0 to establish baseline concentrations of serum metabolites and metabolic hormones. From d 25 until d 90 postpartum cows were separated from feed at 0500 twice weekly (Monday and Friday), and blood samples were collected to determine concentrations of serum progesterone as an indicator of the onset of corpus luteum function. In addition, blood samples were collected over a 4-d period starting at d 30, d 60, and d 90 postpartum for determination of blood metabolites and metabolic hormones. To partially account for diurnal variation, four a.m. and four p.m. blood samples were collected during the collection period. Collection times in relation to feeding were 0, 3, 6, 9, 12, 15, 18, and 21 h with 0 representing immediately prior to supplementation. All blood samples were collected from the coccygeal vein via venipuncture using 10-mL untreated Vacutainer (Becton Dickinson Company, Franklin Lakes, NJ) tubes. Samples were allowed to coagulate overnight at 4°C, and serum was separated by centrifugation (700 x g), and stored at -20°C until analysis.
Beginning on d 25 postpartum and every 30 d thereafter, a mixture of Cr2O3 and flour was fed in pelleted form to provide 10 g/d Cr2O3 for 9 d (Alderton et al., 2000). Following an initial 5-d adaptation period, fecal grab samples were collected before blood sampling twice daily for 4 d. Fecal samples were dried at 55°C, ground using a Wiley Mill (2-mm screen), and composited on an equal DM weight basis.
Milk production was measured on d 30, d 60, and d 90 postpartum using a modified weigh-suckle-weigh technique (Alderton et al., 2000). Each cow was administered a 2-mL i.v. injection of oxytocin after calf removal at 0530 and then milked using a mechanical milking device with remaining milk hand-stripped. Cows were then fed supplement and allowed access to hay, water, and trace-mineralized salt. Six hours later cows were given a second 2-mL injection of oxytocin and milked as described above. Six-hour milk production was extrapolated to 24 h. A subsample (approximately 50 mL) was commercially analyzed (Minnesota DHIA; Zumbrota Laboratory, Zumbrota, MN) for milk fat, protein, total solids, solids nonfat, and somatic cells.
A subsample of each supplement was collected daily and composited over a 2-wk period for analysis. Hay samples were collected by obtaining a core sample from each bale fed. Hay and supplement samples were ground (Wiley Mill, 2-mm screen) for analysis.
Laboratory Analysis
Hay and supplement samples were analyzed in accordance with AOAC (1990) for DM, ash, and CP. Neutral and acid detergent fiber were determined using procedures described by Goering and Van Soest (1970) except that Whatman 541-hardened ashless filter papers (Whatman, Hillsboro, OR) were used instead of fritted disks. Hay and supplement samples were analyzed for in vitro OM disappearance (Judkins et al., 1990). Fecal samples were analyzed for DM, ash (AOAC, 1990), and Cr (Hill and Anderson, 1958) using atomic absorption spectroscopy. Fecal Cr values were used to estimate forage intake as described by Alderton et al. (2000).
Serum samples collected twice weekly were analyzed for progesterone (Eggleston et al., 1990). Inter- and intraassay CV for progesterone were 17.5 and 18.8%, respectively. Onset of the first postpartum estrus was considered to occur 4 d before a rise in concentrations of serum progesterone > 1 ng/mL. Heifers were observed for estrous behavior twice daily beginning at d 50 postpartum, and cows were bred by artificial insemination 12 h following estrus. Heifers were placed with a bull for approximately 60 d following completion of the supplementation period. Day of conception was deduced by subtracting 285 d from the calving date.
Serum samples collected at d 0, d 30, d 60, and d 90 postpartum were analyzed by RIA for insulin (Diagnostic Products Corporation, Los Angeles, CA), IGF-I (Funston, et al., 1995), and GH (Hoefler and Hallford, 1987). Serum glucose (Sigma 16; Sigma Chemicals, St. Louis, MO) and NEFA (NEFA-C; Wako Chemicals, Dallas, TX) were analyzed by commercially available kits. Intra- and interassay CV were 8.5 and 10.9%, 9 and 13%, and 13 and 20% for insulin, IGF-I, and GH, respectively. Samples for glucose and NEFA were analyzed in a single assay with intraassay CV of 7.3 and 9.9%, respectively. Serum samples obtained at d 0 and those collected immediately before feeding of the supplements on d 30, 60, and 90 were analyzed for IGF-binding proteins using ligand blot procedures (Funston et al. 1995; Funston et al., 1996).
Statistical Analysis
Two calves died during the treatment period due to causes unrelated to experimental treatment. One calf from the linoleate-supplemented group died early in the experimental treatment period, and another calf was successfully grafted onto the cow. Calf data from this cow were removed for analysis. A calf from the oleate-supplemented group died near the end of the experiment. That calf had been gaining weight comparable with its contemporaries; therefore, its data were not removed from the data set. However, due to the influence of suckling on postpartum anestrous, conception data for this cow were removed from the data set.
Initial cow BW and body condition score, and calf birth weights were analyzed as one-way ANOVAs using GLM procedures of SAS (SAS Inst. Inc., Cary, NC). Since these initial traits did not differ among groups, the need for covariant analysis was precluded. Cow postpartum interval, days to conception, and adjusted weaning weights were analyzed by one-way ANOVA using GLM procedures of SAS (Ver. 8.0; SAS Inst. Inc.). Rate of conception and cows cycling within the 90-d treatment period were analyzed using Chi Square procedures of SAS (SAS Inst. Inc.).
Data for intake, body condition score, cow and calf weight, and weight change over the 90-d supplementation period, milk production and composition, were analyzed using GLM procedures of SAS (SAS Inst. Inc.) with treatment, day, and treatment x day interactions tested as main effects. Animal-within treatment was used as the error term for treatment effects. Differences among means were separated using Fisher’s protected LSD (Steele and Torrie, 1980). Type III sums of squares were used, and least square means and associated standard errors are reported.
Concentrations of serum metabolites and metabolic hormones were first analyzed as a split-split plot to determine any treatment x time, time x day or treatment x time x day effects using GLM procedures of SAS (SAS Inst. Inc.). Treatment x time effects were tested using animal-within treatment x time as the error term, whereas other interactions were tested with residual error. No treatment x time, time x day, or time x treatment x day effects were noted for any of the serum metabolites or metabolic hormones; therefore, average values for the 24-h collection period at d 30, d 60 and d 90 were analyzed using GLM procedures of SAS (SAS Inst. Inc.) with treatment as the main effect, and day and treatment x day interactions tested as subplot effects. Animal-within treatment was used as the error term for treatment effects. Differences among means were separated using Fisher’s protected LSD (Steele and Torrie, 1980). Type III sums of squares were used, and least square means and associated standard errors are reported.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
). Total OM (P = 0.65) and forage (P = 0.66) intake did not differ among supplemental treatments at any sampling period. Estimated forage intake at d 30, d 60, and d 90 averaged 10.2, 10.2, and 10.1 (± 0.4) kg, respectively.
|
0.38) or treatment x day interactions (P 0.34) detected for percentage milk protein, milk solids nonfat, total solids, or somatic cell count. A treatment x day interaction, however, was detected (P = 0.04) for milk fat percentage. Percentage milk fat was similar (P 0.12) for all treatment groups at d 30; however, at d 60 corn-soybean and oleate-supplemented cows had greater (P 
0.05) percentage milk fat than linoleate-supplemented cows [3.53, 3.72 vs. 3.27 (± 0.09), respectively]. At d 90 cows fed the corn-soybean (P = 0.005) and oleate supplement (P = 0.05) had greater percentage milk fat than linoleate supplemented cows [3.88, 3.76 vs 3.51 (± 0.09), respectively].
Cows had similar body condition scores (P = 0.38; 5.5 ± 0.02) and BW (P = 0.87; 487.9 ± 10.5) before initiation of supplemental diets. Treatment did not affect cow BW (P = 0.62; Figure 1), BW change (P = 0.33) or cow BW change over time (P = 0.29). By the end of the 90-d feeding period, average weight loss in oleate, linoleate, and corn-soybean supplemented cows was 32.6, 16.3, and 21.1 (± 6.0) kg, respectively. Weight change between each sampling period was, -43.2 kg from d 0 to d 30, -28.6 kg from d 30 to d 60, and -15.6 (± 6.5) kg from d 60 to 90. Although there were no significant effects of type of supplement on cow BW or BW change, there was an effect of treatment on cow body condition score (P = 0.02; Figure 1), and a tendency for an effect of treatment on body condition score over time (P = 0.06). Overall, cows consuming oleate supplement had a lower body condition score (4.9 ± 0.06) than those fed linoleate (P = 0.005; 5.1 ± 0.06) or corn-soybean (P = 0.06; 5.0 ± 0.06) supplements. Overall body condition of cows consuming corn-soybean supplement did not differ (P = 0.32) from linoleate-supplemented cows. However, at d 30 and d 60, corn-soybean supplemented cows had a higher (P 0.02) body condition score than oleate-supplemented cows. At d 60 linoleate-supplemented cows had a greater (P 0.0001) body condition score than oleate-supplemented cows; and at d 90, linoleate-supplemented cows had a greater (P 0.04) body condition score than either corn-soybean or oleate-supplemented cows.
|
Calf Performance
Birth weights were similar (P = 0.90) across treatment groups. Calf weight gains during the supplemental period were not influenced by supplement group (P = 0.27) and averaged 30.5, 29.9, and 32.6 (± 1.3) kg for each 30-d period postpartum. In addition, 205-d adjusted weaning weights did not differ (P = 0.48) and averaged 200.1, 199.3, and 207.9 (± 5.5) kg for corn-soybean, linoleate and oleate treatments, respectively.
Metabolic Hormones and Metabolites
Serum concentrations of insulin, IGF-I, and GH were similar (P 0.16) on d 0 and were not affected (P 0.18) by any treatment x time interactions. Therefore, values were averaged across the 24-h sampling periods at d 30, d 60, and d 90 to evaluate treatment effects. Supplement treatment did not influence serum concentrations of insulin (P = 0.18), IGF-I (P = 0.92), or GH (P = 0.19) nor were there any significant treatment x day interactions (P 0.24). Concentrations of insulin and IGF-I, however, increased (P 0.001) from d 30 to d 90 postpartum (Figure 2). Conversely, concentrations of GH decreased (P = 0.006) over the postpartum period (Figure 2). Serum concentrations of glucose and NEFA were not influenced by any time x treatment interaction (P 0.60). Concentrations of glucose (66.7 ± 1.0 mg/dL) and NEFA (0.328 ± 0.02 mEq/mL) were not affected (P 0.38) by supplement treatment. Supplement treatment also did not influence (P 0.11) relative concentrations of any IGF binding proteins nor were there any treatment x day interactions (P 0.10). However, IGF binding protein-2 decreased (P 0.001) over the postpartum period. In contrast, IGF binding proteins-3 and -4 increased (P 0.03) with time postpartum (Table 3).
|
|
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
Eastridge et al. (1988) noted a decrease in milk production, but not percentage milk fat, when dairy cows were fed a diet containing 8% added soybean oil. When blended fats with mixed fatty acid content made up a smaller proportion of the total diet, however, milk production was not affected (Drackley et al. 1998) or increased slightly (Canale et al., 1990). In the present study, extrapolated 24-h milk production was not affected by supplemental treatments; however, there was a treatment x day interaction for percentage milk fat. Percentage milk fat was greater at d 60 and d 90 in corn-soybean and oleate-supplemented cows than in linoleate-supplemented cows. Bernard and Calhoun (1997) noted a decrease in percentage milk fat and milk fat production in dairy cows fed supplements containing raw soybeans and extruded cottonseeds compared with cows fed a whole cottonseed supplement. Because of the enhanced availability of oil in extruded cottonseeds and the elevated linoleate content in soybeans, the formation of trans-fatty acids from polyunsaturated fatty acids (e.g., linoleic acid) oils may suppress milk fat production in dairy cows (Selner and Schultz, 1980) and reduce percentage milk fat in linoleate-supplemented cows.
Cows fed oleate supplement lost the most body condition throughout the supplemental feeding period, whereas linoleate-supplemented cows finished the feeding trial with greater body condition scores than either oleate- or corn-soybean-supplemented cows. Such differences also appear to be associated with trends for changes in BW. The greater loss in body condition score by oleate-supplemented cows may be due in part to the increase in milk fat production during peak lactation. Cows supplemented with calcium soaps of fatty acids had more pronounced losses in body condition early in lactation compared with cows fed a control diet; however, recovery of body condition was slower and less pronounced in control cows (Sklan et al., 1989, 1991). Since differences in serum concentrations of NEFA were not noted, it is unlikely that safflower seed supplementation differentially affected lipolysis (Chilliard, 1993). Alternatively, the decrease in milk fat production noted in linoleate-supplemented cows at d 60 and d 90 could have allowed more nutrients to be used for body reserves.
Other studies have reported positive effects of feeding different fats on reproductive performance. Cows fed soybean oil had increased numbers of medium-sized ovarian follicles during a synchronized estrus within 3 wk of supplementation (Thomas et al., 1997). High-linoleic or -oleic safflower seeds fed prepartum increased overall pregnancy rates in primiparous cows (Lammoglia et al., 1997), and calcium soaps of fatty acids fed to cows in poor body condition increased the number of cows bred during the first half of the breeding season (Espinoza et al., 1995). The lack of a beneficial effect of oilseed supplementation on reproductive performance in the present study may be due to the moderate body condition of the cows. Ryan et al. (1994) noted that follicular development in fat-supplemented cows with body condition score of 3 and 4 lagged behind that of cows in better condition. However, by d 15, postpartum cows in body condition score 4 had numbers of medium and large follicles similar to cows in body condition score 6. Although differences in cow body condition score were noted in the present study, their magnitude was probably not sufficient to elicit overall differences in reproductive performance. The directional change in body condition score prior to rebreeding, however, may be of more importance. Houghton et al. (1990) showed that cows in moderate body condition and increasing at the time of insemination had better conception rates than did cows in moderate body condition and losing condition at the time of insemination.
Espinoza et al. (1995) noted increased calf weight gains when dams were supplemented pre- and postpartum with calcium soaps of fatty acids. In that study, cows decreased in body condition score from 4.1 at d 35 postpartum to 2.5 at 50 d postpartum. In the present study, cows changed from a body condition score of approximately 5.5 at parturition to 4.7 by 90 d postpartum. Hence, potential beneficial effects of feeding supplemental fat on calf performance may be more pronounced in dams in poor body condition. Although Melton et al. (1967) and Rutledge et al. (1971) concluded that milk quantity influenced calf growth to a greater extent than milk quality, Christian et al. (1965) emphasized the importance of butterfat to calf gain especially when other sources of variation (i.e., availability of creep feed, quantity of milk) were kept constant. Even though percentage milk fat differed among linoleate and oleate cows in the present study, differences in weaning weights were not detected perhaps because of the availability of forage and the potential for cross-suckling in this confined study.
Consistent effects of fat supplementation on concentrations of insulin and glucose were not apparent in the current study perhaps due to the ability of dietary fatty acids to decrease de novo fatty acid synthesis in mammary and adipose tissue and to stimulate hepatic gluconeogenesis (Chilliard, 1993). Likewise, fat supplementation does not appear to consistently influence the secretion of GH (Chilliard, 1993; present study). Infusion of soybean oil emulsion decreased circulating concentrations of GH in ovariectomized ewes (Estienne et al., 1989). Supplementation, however, with soybean oil, fish oil, or animal tallow increased GH in cows (Thomas et al., 1997).
Circulating (Roberts et al., 1997), ovarian (Thomas et al., 1997; De Fries et al., 1998), and pituitary (Roberts et al., 2001) concentrations of IGF-I have been implicated as mediators of the effects of nutrition on reproduction (Snyder et al., 1999). Furthermore, specific IGF binding proteins present in the circulation or specific tissues can inhibit or potentiate effects of IGF-I. The decline in levels of IGF binding protein-2 noted over time postpartum in the current study is consistent with observations that elevated levels of this binding protein are inversely related to the secretion of LH (Snyder et al., 1999; Kiyma et al., 2001) and duration of postpartum anestrous (Roberts et al., 2001).
Since cows in the current study were in moderate body condition and the postpartum interval was not influenced by supplementation, the lack of significant effects on metabolic hormones is not surprising. The reinitiation of fertile estrous cycles following parturition is of low priority when there are competing demands for a limited supply of nutrients (Short et al., 1990). Based on the observation that linoleate and oleate supplements differentially influenced changes in body condition score and percentage milk fat, we speculate that appropriate fat supplementation may provide a method to selectively influence nutrient partitioning.
|
Implications |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
|
Footnotes |
|---|
2 Current address: RR2 Box 135A, Beloit, KS 67420.
Received for publication December 21, 2001. Accepted for publication March 8, 2002.
|
Literature Cited |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionImplicationsLiterature Cited |
|---|
This article has been cited by other articles:
|
|
 |
|
  N. M. Long, G. M. Hill, J. F. Baker, W. M. Graves, D. H. Keisler, and B. G. Mullinix Jr. Case Study: Reproductive Performance of Beef Cows Fed Whole Soybeans Before the Breeding Interval Professional Animal Scientist, December 1, 2008; 24(6): 639 - 647. [Abstract] [PDF]
|
|
|
|
 |
|
 J. P. Banta, D. L. Lalman, C. R. Krehbiel, and R. P. Wettemann Whole soybean supplementation and cow age class: Effects on intake, digestion, performance, and reproduction of beef cows J Anim Sci, August 1, 2008; 86(8): 1868 - 1878. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. W. Hess, G. E. Moss, and D. C. Rule A decade of developments in the area of fat supplementation research with beef cattle and sheep J Anim Sci, April 1, 2008; 86(14_suppl): E188 - E204. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Lake, T. R. Weston, E. J. Scholljegerdes, C. M. Murrieta, B. M. Alexander, D. C. Rule, G. E. Moss, and B. W. Hess Effects of postpartum dietary fat and body condition score at parturition on plasma, adipose tissue, and milk fatty acid composition of lactating beef cows J Anim Sci, March 1, 2007; 85(3): 717 - 730. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Lake, E. J. Scholljegerdes, T. R. Weston, D. C. Rule, and B. W. Hess Postpartum supplemental fat, but not maternal body condition score at parturition, affects plasma and adipose tissue fatty acid profiles of suckling beef calves J Anim Sci, July 1, 2006; 84(7): 1811 - 1819. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Lake, E. J. Scholljegerdes, W. T. Small, E. L. Belden, S. I. Paisley, D. C. Rule, and B. W. Hess Immune response and serum immunoglobulin G concentrations in beef calves suckling cows of differing body condition score at parturition and supplemented with high-linoleate or high-oleate safflower seeds J Anim Sci, April 1, 2006; 84(4): 997 - 1003. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Lake, E. J. Scholljegerdes, D. M. Hallford, G. E. Moss, D. C. Rule, and B. W. Hess Effects of body condition score at parturition and postpartum supplemental fat on metabolite and hormone concentrations of beef cows and their suckling calves J Anim Sci, April 1, 2006; 84(4): 1038 - 1047. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Lake, E. J. Scholljegerdes, V. Nayigihugu, C. M. Murrieta, R. L. Atkinson, D. C. Rule, T. J. Robinson, and B. W. Hess Effects of body condition score at parturition and postpartum supplemental fat on adipose tissue lipogenic activity of lactating beef cows J Anim Sci, February 1, 2006; 84(2): 397 - 404. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. L. Lake, E. J. Scholljegerdes, R. L. Atkinson, V. Nayigihugu, S. I. Paisley, D. C. Rule, G. E. Moss, T. J. Robinson, and B. W. Hess Body condition score at parturition and postpartum supplemental fat effects on cow and calf performance J Anim Sci, December 1, 2005; 83(12): 2908 - 2917. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. L. Martin, R. J. Rasby, D. R. Brink, R. U. Lindquist, D. H. Keisler, and S. D. Kachman Effects of supplementation of whole corn germ on reproductive performance, calf performance, and leptin concentration in primiparous and mature beef cows J Anim Sci, November 1, 2005; 83(11): 2663 - 2670. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. W. Hess, S. L. Lake, E. J. Scholljegerdes, T. R. Weston, V. Nayigihugu, J. D. C. Molle, and G. E. Moss Nutritional controls of beef cow reproduction J Anim Sci, June 1, 2005; 83(13_suppl): E90 - 106. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. J. Scholljegerdes, B. W. Hess, G. E. Moss, D. L. Hixon, and D. C. Rule Influence of supplemental cracked high-linoleate or high-oleate safflower seeds on site and extent of digestion in beef cattle J Anim Sci, December 1, 2004; 82(12): 3577 - 3588. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. N. Funston Fat supplementation and reproduction in beef females J Anim Sci, January 1, 2004; 82(13_suppl): E154 - 161. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
