IMPROVING GROWTH AND LACTATION OF RUMINANTS

Abstract: Disclosed is a method for increasing the growth rate of ruminants which comprises administering orally to the ruminant an effect amount of carnitine. Also disclosed is a feed formulation for ruminants which comprises carnitine.

Description: IMPROVING GROWTH AND LACTATION OF RUMINANTS FIELD OF THE INVENTION The present invention is in the general field of nutrition for ruminant animals, such as cattle and sheep. In a particular aspect, it relates to a method of feeding or infusing ruminant animals with a formulation which enhances the growth of the animals and/or improves the content of the milk produced by lactating animals, as evidenced, for example, by an increase in the solid-not-fat (SNF) component of the milk. Ruminant animal diets or infusions of this invention include an amount of a camitine, such as L- carnitine or a L-carnitine salt. The amount present in the diet or infusion is such that the growth of the animal is increased and/or the content of particular desirable components of the milk produced by lactating animals is improved over those animals not fed this diet or receiving the infusion. BACKGROUND OF THE INVENTION Recent studies on the function of camitine in metabolism in lactating ruminants have found that camitine stimulates the ketogenesis of palmitate in ovine hepatocytes (Faulkner et al. Comp Biochem Physiol [BJ 9S(2-3):283-6, 1991) and increased hepatic oxidation in bovine liver (Drackley et al. J Dairy Sci 74(9):3014-24, 1991). The presence of propionate blocked both of these effects. Both of these studies were done on a cellular level, and involved the addition of camitine and propionate in vitro. Camitine has been used as a feed additive for starter pigs (Blum et al. , U.S. Patent No. 5,192,804), for finishing pigs in combination with lysine (Blum et al. , U.S. Patent No. 5,124,357), for poultry (Blum et al. , U.S. Patent Application 08/049,258), for catfish (Blum et al. , U.S. Patent No. 5,030,657) and for domesticated dogs and cats (Keene et al., U.S. Patent No. 4,883,672). JP 0126420 teaches the addition of camitine for animals and humansas a growth stimulator. However, none of these feed are formulated for the use of ruminant animals, nor is there any suggestion that ruminants would display an increase in growth rate or an improvement in the content of milk or the components of the milk or the digestability of the feed of lactating ruminants with the feeding of ca itine. Additionally, none of these report the infusion of camitine directly into the stomach of the animal. Tables 1 and 2 summarize a number of patents related to methods, generally feed additives, which increase growth rate and/or increase in lactation of rumi¬ nants. However, none of these methods involve the use of camitine. TABLE 1 INCREASE GROWTH RATE Patent No. Date Inventor Additive Purpose 5,202,136 04/13/93 Evans et al. saturated fat (at weight gain rate least 10C) 4,760,909 07/26/88 Nissen et al. ketoisocaproate increase weight gain or wool 4,353,902 10/12/82 Hedde et al. histamine H2 increase growth receptor agonist 4,258,031 03/24/81 Fletcher et ronnel/monersin increase growth al. 4,211,775 07/08/80 Ioset ronnel increase growth 4,186,212 01/29/80 Howell HMW/aliphatic increase alcohols metabolic energy 4,087,554 05/02/78 Haydock et iodonium salts increase growth al. rate/feed effciency 3,953,606 04/27/76 Demkovich uroidotetralin increase growth et al. rate 3,210,194 10/05/65 Burroughs 2- promote mercaptoimidazole/c growth/increase arotine feed utilization 2,951,759 09/06/60 DeZeiw et glucocorticoid growth stimulus al. TABLE 2 INCREASE LACTATION Patent No. Date Inventor Additive Purpose 5,141,922 01/29/80 Krivi val 126 BGH enhance lactation 5,041,452 08/20/91 White diamides increase feed util. /lactation 4,978,682 12/18/90 White diethanolamine increase feed triacetic acid util ./lactation 4,966,917 10/30/90 White tetramide increase feed util ./lactation 4,895,951 08/20/91 White heterocyclic increase feed diamides util ./lactation 4,883,820 11/28/89 White tetramide increase feed util. /lactation 4,882,355 12/18/90 White diethanolamine increase feed triacetic acid util. /lactation triamides 4,801,618 11/28/89 White diamino tetramides increase feed util ./lactation 4,800,213 12/18/90 White diethanolamine increase feed triacetic triamides util. /lactation 4,783,524 11/08/88 Kotts et al. bovine IGF-II increase (peptides) growth/lactation 4,704,276 11/03/87 Kantor antibiotic LL- increase growth E19020 rate/feed util. /lactation 4,534,969 08/13/85 Phillips antibiotic increase lactation teichomycin 4,430,328 02/07/84 Scheifinger glycopeptide increase lactation antibiotics 4,336,250 06/22/82 Scheifinger virginiamyan/elfa increase milk mycin production All of the patented methods involve the addition of compounds other than camitine, many of which are expensive and may have other unwanted effects on the animal. Therefore, there remains a need in the art for a method of increasing growth rate of ruminants and/or altering milk content of lactating ruminants or increasing digestability of the feed which is inexpensive and does not affect other aspects of the mminants' health. Accordingly, one aspect of the present invention is a diet for mminants which comprises an effective amount of camitine, where the desired effect is an increase growth rate and/or a desirable alteration in the content of milk produced by lactating ruminants. A further aspect of the present invention is a method of increasing growth rate of mminants which involves feeding the mminants a standard diet which has been supplemented with an effective amount of camitine. This method can also be achieved by infusion of the camitine directly into the absomassum of the animal. A still further aspect of the present invention is a method of altering the content of milk produced by lactating mminants which involves feeding the ruminants a standard diet which has been supplemented with an effective amount of camitine. As above, this method can also be achieved by infusion of the camitine directly into the absomassum of the animal. SUMMARY OF THE INVENTION It has now been discovered that by feeding camitine to mminants, or infusing camitine into the abomasum, there is an increase in growth rate of the animal. Further, if the ruminant is lactating, there is a desirable alteration in the content of the milk produced. This is achieved by feeding mminants a diet which comprises an effective amount of camitine. Alternatively, the camitine can be infiised directly into the abomasum of the animal. Specifically, it has been discovered that camitine supplementation increases average daily gain, indicating an increase in growth rate. In lactating ruminants, camitine supplementation has been found to increase SNF content, which is potentially important with more markets moving to pricing milk on the basis of SNF or protein. This treatment has also been shown to change in nitrogen retention and utilization which is important for improving production efficiency, and also will become increasingly important from the standpoint of decreasing nitrogen excretion into the environment. Finally, an improvement in digestibilities of fatty acids, fiber, energy, and crude protein by dairy cows with camitine supplementation offers potential for increasing productive efficiency. DETAILED DESCRIPTION OF THE INVENTION All patent applications, patents, and literature references cited in this specification are hereby incorporated by reference in their entirety. The present invention relates to a diet or infusion for mminants which comprises camitine. The camitine is present in concentrations which make the diet or infusion suitable for use in the method of the present invention. The present method increases growth rate, as indicated by an increase in ADG and desirably alters the content of lactating mminants treated by this method, as indicated by increased SNF content of the milk produced. Camitine has also been shown to increase mtrogen retention and improve digestabilities of particular components of the cow diet. Because of the increase in SNF, it would be expected that camitine will increase milk volume and/or percentage of fat or protein in the milk. Suitable mminants to be fed the diet of the present invention include but is not limited to beef cattle, dairy cattle, and sheep. Animals of all ages benefit from this treatment method. For example, young animals, which have undeveloped rumen, are expected to respond to a combination of camitine and a "milk replacer" diet in a very similar fashion to older animals which have the camitine infused into the abomasum. The feeding of this diet should occur from birth to 5 months of age. The camitine can be any isomer of camitine, preferably L-carnitine, and can be synthetic, microbial produced, or naturally occurring. Also suitable for formulation of the diet or infusion of the present invention are salts of camitine, such as acetyl camitine. The camitine is present in an effective amount, where the desired effect is an increase in growth rate or a desirable alteration in the content of the milk produced. Given the detailed guidance of the present specification, it is believed within the level of one of ordinary skill to test a range of camitine concentrations using a trial feed in order to optimize the concentration for the particular species and breed being fed or infused. Table 3 lists average feed intake for various sizes and types of ruminants, to be combined with the camitine. The average daily feed intake figures are from "Clinical and Diagnostic Veterinary Toxicology, 2nd ed. , William B. Buck et al. Kendall/Hunt Publishing Co. Dubuque, Iowa. Generally, the effective camitine concentration is between about 125 mg per head per day to about 20 grams per head per day. The preferred amount is dependent on the particular animal being treated and the size of the animal. For specific recurrent nutritional requirements, reference is made to such publications as the 1985 NRC Publication on Sheep, the 1984 Publication on Beef and the 1978 NRC Publication on Dairy Cattle (such references being incorporated by reference herein) and such similar publications as are well known in the art. In feeding or infusing dairy cattle, a preferred amount is approximately 5 grams per head per day. In feeding or infusing beef cattle, a preferred amount is approximately 2 grams per head per day. TABLE 3 Bodv Weight % Feed Intake lbs. kg - Body Weight Beef Cattle 300 136 2.3 450 204 2.5 650 295 2.4 1000 454 2.1 Lactating Cattle 770 350 1.4 1760 500 1.2 Non-Lactating Dairv Cattle 770 350 1.8 1960 800 1.2 59 27 4.5 99 45 3.9 The animal feeds most generally used in conjunction with the method of this invention are composed of various grain mixtures and/or roughage feeds such as hay, cottonseed hulls, rice hulls, silage or other high fiber feedstuff s used in various combinations commonly fed to meat, milk and/or wool-producing mminants. Generally, the feed should contain from 40 to 60 percent by weight of high concentrate diet, the balance of which may be roughage. A fifty-fifty mixture is preferred. Such diets are known to shift the mminal volatile fatty acid (NFA) profile in the direction of more propionate production and less acetate production. This may give increased utilization of enregy and therefore more milk volume. The feed schedule and feed rates can also be any standard schedule and rate used in the art, including feed restrictive programs. Increase in growth rate can be determined by an increase in daily average growth (ADG), increase in backfat or ribfat, increase in feed conversion, or any other art accepted way of measuring growth rate. Milk content of crude protein and protein components, solid-not-fat, fat and fat components can be measured using standard methods well known in the art. The following examples are representative of the present invention but is not to be considered limiting to the scope of the invention. Research was conducted to determine effects of camitine supplementation of stocker heifer and steer diets consisting of good quality hay fed with a com-soybean mal supplement on pasture. Ruminally cannulated steers were fed the diets to determine NFA, and mminal fluid and plasma camitine concentrations over 24-h intervals. Finally, a trial on dairy cows was conducted to determine the effect of camitine of milk production and content, as well as the nutrition effects on the cows themselves. Example 1: Heifer Trial Experimental Procedure: Forty-two (42) beef heifers, approximately 9 months of age (473.4 lb average initial weight) were assigned by breed and weight to six groups of seven heifers. Two groups of heifers were then randomly assigned to each of three L-carnitine treatments: A=No L-carnitine; B=0.6 g L-carnitine/hd daily; C = 1.2 g L-carnitine/hd daily (Table 4). The L-carnitine premixes (Treatments B and C) were added at 1.0% (20 lb/ton) of final diet composed of 75 % ground com and 25 % soybean meal (Table 5). The final diets were fed at 2.5 kg (5.5 lb)/heifer daily in feed troughs in pastures for 42 d. Tifton 85 hay in 55-60 lb square bales was fed free-choice in hay racks. Hay refusals were weighed back periodically to accurately determine hay intake. TABLE 4 EXPERIMENTAL PADDOCKS AND DESIGN OF HEIFER AND STEER TRIALS L-Carnitine, g/hd daily Item 0 0.6 1.2 Heifer trial No. pastures (0.81 ha) 2 2 2 No. heifers 14 14 14 Initial wt. lb. 472 475 474 Steer trial No. pastures (0.81 ha) 2 2 2 No. steers 14 14 14 Initial wt. lb. 508 510 510 TABLE 5 PREMIX AND FINAL DIET COMPOSITION Premix formulation Item Premix A a Premix B Premix C Ground corn, kg(lb) 0 35.409 (78.077) 34.537 (76.154) L-Carnitine, kg(lb) 0 .872 (1.923) 1.744 (3.846) g/lb 0 10.9 21.8 Total 80.0 80.0 L-Carnitine g/hd/day b Final treatment supplement: (A) 0 (b)0.6 (C) 1.2 Com 1500 1480 1480 Soybean meal 500 500 500 Premix (A, B, or C), lb 0 20 20 No premix A was formulated - 0 camitine. b Treatment supplements containing premix A, B, or C fed at 5.5 lb (2.5 kg) per heifer (38.5 lb/day for each pen of 7 heifers) to deliver 0, .6 or 1.2 g carnitine/hd daily. Hay fed free- choice. All heifers were weighed on two consecutive days at the initiation and termination of the trial, and the mean of these respective weights were used as initial and final weights. Heifers were weighed at 21-d intervals, providing two weight periods. On d 21, heifers were rotated on replicate pastures within treatments to remove any pasture effects. On d 1 of the trial, all heifers were injected with Vitamins A and D, injected with Discovery 4L5 ® (IBR, PI3, pneumonia, leptospirosis vaccine) and injected with Tramisol ® . A free-choice trace mineral and vitamin supplement (Nitaminde ® ) was available at all times with free access to water. The two-acre (.81 ha) pastures used in the trial (Table 4) were composed of dormant bermudagrass stubble during the November to January time frame for the experiments. Therefore, the majority, if not all, of the nutrients for the cattle in each trial were supplied by supplemental grain and hay. The heifers had been weaned in early September, therefore they had ample time to recover from weaning stresses and to adapt to grain/hay diets which were provided from weaning time until trials were initiated. All heifers were bom and weaned on University of Georgia Research Farms, therefore they had received similar preweaning and postweaning management. All cattle were apparently healthy when the trial was initiated. The hay utilized as the basic roughage in the heifer trial was from the same hay cutting of well-fertilized Tifton 85 bermudagrass forage. The hay averaged 13.91 % cmde protein and 90.16% dry material (DM), and had a fresh hay odor and bright green color. Hay DM consumption averaged 56.5% of total dry matter intake (DMI) in the Heifer Trial (Table 6). TABLE 6 PERFORMANCE OF WEANED HEIFERS FED L-CARNITINE AND HAY DIETS Item Control 0.6g L- 1.2g L- SE X f Carnitine X Carnitine X R. R 2 R. R 2 R. R 2 No. 7 7 7 7 7 7 In. wt. lb 473 471 472 476 473 475 472 475 474 12. 2 Day 21 wt 483 474 479 507 496 501 489 495 492 12. 3 Gain (42-d), lb a 50 40 45 57 56 56 55 55 55 3.5 ADG lb Day 21 b 0.48 0.19 0.34 1.40 1.07 1.27 0.82 0.94 0.88 0.1 Day 42 c 1.19 0.96 1.07 1.36 1.34 1.35 1.30 1.31 1.30 4 0.0 8 Feed intake, lb Supplement 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 5.5 Suppl. DM C 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 Hay, as-fed 7.6 7.0 7.3 7.0 7.5 7.2 7.4 6.9 7.1 Hay DMI d 6.8 6.3 6.6 6.3 6.7 6.5 6.7 6.2 6.4 Total DMI 11.8 11.3 11.6 11.3 11.7 11.5 11.7 11.2 11.4 DMI 42d 496 475 487 475 491 483 491 470 479 Feed/gain (DM) e 9.9 11.9 10.9 8.3 8.8 8.6 8.9 8.5 8.7 0.6 Treatment means differ (P < 0.06). b Treatment mean differ (P< 0.01). c Supplements fed at 5.5 lb/hd (38.5 lb/pen daily); Est. DM=90.0%. d Hay samples (6 samples from 5 bales; 3 sites/bale) had 90.16% DM and 12.91 % CP. e Treatment means differ (P< 0.12). f Treatment mean In the Heifer Trial (Table 6), the average daily gain (ADG) was variable between replicators and treatments, however 21-d ADG was higher (P < 0.01) for L- carnitine supplemented treatments (26% and 21 % higher for 0.6 and 1.2 g treatments) compared with controls. The 42-d ADG and 42-d gain/heifer were higher (P < 0.06) for L-carnitine supplemented heifers compared with controls. The 42-d ADG was very similar for each replication within each L-carnitine treatment, and 42-d ADG was not improved by feeding 1.2 9/hd daily compared with 0.6 g/hd daily. Although hay was provided free-choice, there were only slight differences in consumption between treatments. Hay was checked for consumption daily, and fresh hay was supplied in amounts estimated to be consumed in 24 h each day. Hay DMI tended to be lower (P > 0.10) for increasing level of L-carnitine supplementation. With increased gain on L- carnitine treatments and similar DMI intake for all treatments, feed conversion efficiency was improved (P < 0.12) by 26.7% and 25.3%, respectively, for 0.6 g and 1.2 g L- carnitine treatments compared with controls. Example 2: Steer Trial A 42-d stocker steer trial was conducted using the same diets, experimental design and treatment assignment procedures, L-carnitine treatments, hay and grain supplements and pastures as described above. The steers were 10 months of age when the trial began and averaged 509.3 lb initially. All of the preliminary injections and treatments described above were administered to the steers on d 1 of the trial. Initial and final weights were means of two consecutive daily full weights. On d 42 of the steer trial, backfat of each steer was determined by using a Renco ® electronic backfat meter. As above, the steers have been weaned in early September. All steers were born and weaned on University of Georgia Research Farm. All were apparently healthy when the trial was initiated. The same cutting of hay was used as above. Hay DM consumption averaged 65.2% of the total DMI in the Steer Trial. In this trial (Table 7), the control steers actually gained slightly more than L-carnitine treatment steers at both d 21 and for the entire 42-d trial. There were no significant differences (P < 0.10) for any treatments in this experiment. The replication 2 steers in each of the L-carnitine treatments tended to have lower gains than replication 1 steers and control steers. Reasons for those differences in performance are not currently known. TABLE 7 The hay intake was higher for steers than for heifers (Tables 6 and 7), primarily because of colder weather later in the season during the Steer trial, and because the BW was greater initially for the steers. Differences in hay consumption (Table 7) among treatments were minimal. Food/gain ratios were lowest for controls, and 15.1 % and 13.1 % higher (P < 0.20), respectively, for 0.6 g and 1.2 g L-carnitine treatments compared with controls. Individual steer backfat depth at the initiation of the trial (d 1) and at d 42 (Table 7) were measured. Treatment means indicated that all steers increased backfat depth during the 42-d trial. Steers fed 0.6 g of L-carnitine apparently had the highest increase in level of backfat, followed by control steers, with the high-level L-carnitine steers (1.2 g/hd daily) posting the smallest amount of change. Variation was quite high for backfat measurements, consequently there were no treatment differences (P > 0.20). It should be noted that one replication of the 1.2 g L-carnitine treatment had a 2.3 mm increase in backfat compared with a 0.1 mm decline in backfat for the other replication. The highest numerical changes in backfat depth were measured for steers on the two L- carnitine treatments. Example 3: Ruminal Cannulated Steer Trial Three mature ruminally cannulated steers (avg. BW 1100 lb) were fed 14.5 lb of the same hay and 11.0 lb of the same L-carnitine treatment supplements described above (control, 0.6 g, or 1.2 g of L-carnitine/hd daily). The average metabolic size of the three ruminally cannulated steers was approximately two times the average of the steers and heifers used in the trials described above, therefore we assumed mmen volume would be approximately twice as large for these steers as for the stocker heifers and steers. Consequently, daily grain/protein supplement and hay were doubled, and held constant, for these steers, resulting in L-carnitine intake of 0, 1.2 or 2.4 g/steer daily. The steers were fed appropriate L-carnitine treatments in a 3 x 3 latin square experiment, allowing each of the three steers to be on each of the L-carnitine diets. Steers were randomly assigned to treatments initially, and followed a statistically designed format for treatment rotation. Each steer was fed the appropriate diet for 10 d in each of three periods, with sample collection over a 24-h period beginning on the morning of the last day of each period. All steers were treated for internal parasite prevention (Tramisol ® ), a respiratory infection prevention (Discovery 4L5 ® ), and injected with vitamins A and D two days before the experiment began. On d 10 of each period, samples were collected beginning at 0700 h, and steers were then immediately fed daily grain/L-carnitine supplements and hay Jugular blood and mminal fluid samples were obtained at 0 h before feeding and at 1, 2, 3, 4, 6, 8, 12, 16, 20 and 24 postfeeding. Ruminal fluid was strained through 6 layers of cheesecloth and pH was immediately determined. Blood samples were processed yielding plasma for plasma urea nitrogen, plasma cholesterol, plasma triglyceride and plasma camitine analyses. Ruminal fluid samples were treated with perchloric acid (1.5 ml/dl of whole ruminal fluid) to stop microbial activity, and then centrifuged (10,000 RPM) to remove larger particles before freezing. Ruminal fluid samples were subjected to analyses to determine VFA and camitine concentrations. Appropriate statistical analyses were performed on data from each of the three trials in cooperation with our staff statistical consultant in the Department of Computer and Statistical Services, CPES, Tifton. Ruminally cannulated steers were fed L-carnitine at 0, 1.2 or 2.4 g/hd daily utilized the same hay source with grain L-carnitine protein supplement and hay intake was adjusted to provide the same proportions of hay and grain as consumed in Examples 1 and 2. This procedure was designed to account for differences in mminal size and BW of ruminally cannulated steers compared with younger weaned steers and heifers utilized above. This trial was designed to provide information on mminal degradation rates for L-carnitine, effects of L-carnitine supplementation on mminal VFA production which affects energy metabolism in mminants, and to observe changes in plasma camitine levels over time when relatively high levels of dietary L-carnitine were ingested. Plasma urea nitrogen (PUN), plasma cholesterol and plasma triglyceride concentrations averaged over 11 sampling times within 24 h are shown in Table 8 for three dietary treatments with supplemental L-carnitine. There were no differences (P > 0.20) for dietary L-carnitine treatments for PUN, cholesterol or triglycerides, however, PUN concentrations were different (P < 0.01) over time. Cholesterol and triglyceride concentrations were not affected (P > 0.10) by sampling time. Figure 1 shows a gradual increase in PUN concentrations after feeding for all three dietary treatments, followed by a gradual decline after 12 h with 24 h concentrations returning to those observed a 0 h, before feeding. These results suggest that L-carnitine supplementation at high levels on a relatively high roughage diet has very little, if any effect on nitrogen uptake from the rumen. TABLE 8 PLASMA UREA NITROGEN. PLASMA CHOLESTEROL AND PLASMA TRIGLYCERIDE VALUES FOR STEERS FED THREE L-CARNITINE LEVELS OVER TIME Item Added dietary L-carnitine (g/d) 0 1.2 g 2.4 g SE No. observations 3 33 33 33 PUN, mg/dl 19.6 19.2 19.6 0.6 Plasma cholesterol, mg/dl 96.5 99.2 102.0 1.0 Plasma triglyceride mg/dl 22.1 22.1 22.8 0.6 a Mean of data collected at 11 times during a 24 h period in a 3 x 3 latin square using 3 ruminally cannulated steers. Table 9 shows ruminal fluid VFA in molar percentages averaged over 6 sampling times in a 24 h period. Key sampling times of 0, 2, 4, 8, 16 and 24 h were done. Previous research with L-carnitine supplementation had shown no treatment effects when L-carnitine was fed to feedlot cattle on high concentrate diets. The VFA means (Table 8) were remarkably similar (P > 0.10) for each individual VFA assayed. Ruminal fluid pH means were unaffected (P > 0.10) by L-carnitine supplementation, however pH was affected (P < 0.06) by sampling time, with slight decreases occurring at 1 h and 6 h postfeeding. Ruminal fluid pH ranged from 6.3 to 6.6 throughout the study, well within acceptable ranges for the kind of diet being fed. TABLE 9 RUMINAL FLUID VOLATILE FATTY ACIDS (VFA) AND PH MEASURED OVER TIME IN STEERS FED THREE LEVELS OF L-CARNITINE Item Added dietary L-carnitine (g/d) 0 1.2 2.4 SE No. observations 3 18 18 18 VFA, mol/100 mol Acetic 67.0 67.2 67.5 .32 Propionic 17.2 17.5 17.0 .8 Isobutyric 1.6 1.5 1.6 .1 Butyric 11.0 10.7 10.8 .5 Isovaleric 2.1 2.0 2.0 .03 Valeric 1.1 1.1 1.1 .01 Acetate/propionate 3.9 3.9 4.0 .2 Total VFA, μM/liter 93.1 92.6 94.4 1.2 Ruminal fluid pH b 6.41 6.41 6.38 .04 a Means based upon six samples over 24 h intervals at 3 periods in a 3 x 3 latin square experiment using 3 ruminally cannulated steers. b Means for pH based upon 33 samples per steer over 11 sampling times in three 24 h periods in the 3 x 3 latin square experiment using three ruminally cannulated steers. The changes in VFA concentrations with time are shown in Figures 2, 3 and 4. There were no treatment effects for acetate and propionate over a 24 h period (Table 9), but acetate and propionate concentrations were affected (P < 0.05) by time of sampling. In Figure 2, ruminal acetate tended to decrease between 2 h and 16 h postfeeding, with a sharp increase between 16 b and 24 h. Corresponding increases in propionate concentrations were observed when acetate concentrations declined, and propionate declined slightly after 16 h when acetate increased. These trends in acetate and propionate concentrations may be explained by digestion of grain portion of the diet during the interval from 2 h to 16 hr, which probably contributed to the classic shifts in acetate and propionate concentrations. Although not statistically significant, propionate concentrations were lower on the L-carnitine treatments from 4 h to 16 h postfeeding compared with the controls. The acetate: propionate ratios were affected (P < 0.05) by time, but the means over the 24 h period were not affected by treatment (Table 9). In Figure 3, isobutyrate was unaffected by time or treatment (data at bottom of Figure 3). Butyrate concentrations (Figure 3, Top), were affected (P < 0.01) by time, but not by treatment (P > 0.10). Butyrate concentrations for all treatments tended to increase after feeding at 0 h, and remained slightly elevated until 16 h postfeeding, when all treatments declined to approximately the same concentrations at 24 h as the initial concentrations at 0 h. Significance of these changes is unknown, especially since plasma triglycerides were unaffected by time or treatment. Figure 4 and Table 9 show concentrations of branched chain VFA isovalerate and valerate, which are often considered minor YFA for nutrition of mminants. Isovalerate concentration fluctuated with time, resulting in a time effect (P < 0.05), and a trend (P > 0.10) for depressed isovalerate concentrations compared with controls throughout the 24 h period. Valerate concentrations increased (P < 0.01) over time (Figure 4) from 0 h to 4 h, and gradually declined from 4 h to 16 h, and then remained stable through 24 h, returning to levels observed at 0 h. The statistical analyses indicated treatment differences (P < 0.01) for valerate. Example 4: Dairy Cows Trial Experimental Procedure: This trial was a replicated 3 x 3 latin square design using 6 multiparous Holstein cows that averaged 51 days into lactation at the start of the experiment. Therefore, there were 6 observations per treatment for all variables. Periods were 21 days long, with the first 14 days for adaptation and the last 7 for data collection. Treatments were 1) control (no camitine), 2) L-carnitine dosed into the mmen, and 3) L- carnitine infused continuously into the abomasum. Measurements of digestibilities and balances of energy and nitrogen were made by total collection of feces and urine. Cows were fed a total mixed diet The ingredients of this diet are summarized Table 10 and chemical composition is summarized in Table 11. L-Carnitine was administered at a mean of 5.96 g/d, which is the equivalent to 227 ppm in diet dry matter, based on actual dry matter intakes. TABLE 10 INGREDIENT COMPOSITION OF TOTAL MIXED DIET Ingredient % of DM Alfalfa haylage 30.00 Com silage 20.00 Soyhulls, pelleted 4.00 Soybean meal 14.00 Com, ground shelled 25.90 Energy Booster 3.00 Sodium bicarbonate 0.75 Magnesium oxide 0.15 Dicalcium phosphate 1.00 Limestone 0.85 Sodium chloride 0.20 DI Dairy Min/Vit 0.15 TABLE 11 CHEMICAL COMPOSITION OF TOTAL MIXED DIET ^McaϊTkg The experimental design was balanced with respect to carry-over effects, and all variables were tested statistically for presence of significant carry-over affects. If carry-over effects were detected, direct-effect means were calculated, which in effect are means "adjusted" to remove the carry-over affects. Statistical contrasts used were 1) control vs. L-carnitine treatments, and 2) ruminally delivered L-carnitine vs. abomasally infused L-carnitine. As seen in Table 12, feed intake and milk production were not affected significantly by L-carnitine. However, the content of solids - not-fat (SNF) in milk was increased by either ruminal or abomasal L-carnitine (see, line 6). Because milk protein fractions were not altered significantly by L-carnitine (Table 13), the increase in SNF may be attributable to increased lactose content (which was not measured directly). Abomasally infused L-carnitine tended to decrease milk fat content and decreased milk fat yield. The fatty acid composition of milk fat was not altered appreciably by L-carnitine (Tables 14 and 15). TABLE 12 EFFECT OF ADMINISTRATION OF L-CARNITINE INTO THE RUMAN OR ABOMASUM ON DMI. MILK YIELD AND MILK COMPOSITION Treatments Contrast (P) Item Control Ruman Abonasu SEM Control vs. Ruman vs. L-Carnitine Abomasu m DMI, kg/d 1 26.3 26.3 26.0 0.59 0.89 0.79 Milk, kg/d 41.6 42.2 41.0 0.68 0.99 0.26 3.5% FCM, kg/d 42.2 43.1 40.8 0.41 0.64 0.01 CP, % 2 3.09 3.08 3.08 0.02 0.57 0.84 CP, kg/d 1.29 1.30 1.27 0.02 0.96 0.35 SNF, % 7.94 8.16 8.09 0.05 0.02 0.34 SNF, kg/d 3.31 3.45 3.32 0.07 0.41 0.25 Fat, % 3.59 3.64 3.47 0.06 0.52 0.51 Fat, kg/d 1.49 1.63 1.42 0.01 0.41 0.002 'Carryover effect />= 0.095 Direct effect means 26.0 25.2 27.3 0.76 0.08 Carryover effect p= 0.042 Direct effect means 3.05 3.05 3.14 0.19 0.04 TABLE 13 EFFECT OF ADMINISTRATION OF L-CARNITINE INTO THE RUMEN OR ABOMASUM ON N COMPONENTS OF MILK Item Treatments SEM Contrast (P) Control Rumen Abomasum Control Rumen vs. vs. Camitine Abomasu m Total N %' 0.485 0.482 0.483 0.003 0.57 0.84 g/d 201.8 203.8 198.7 3.6 0.89 0.35 True N % 2 0.451 0.450 0.450 0.003 0.63 0.89 g/d 188.0 190.0 185.0 3.3 0.92 0.33 % of total N 93.16 93.21 93.20 .08 0.67 0.95 Casein N % 0.353 0.353 0.349 0.002 0.33 0.15 g/d 147.2 1491 143.4 2.1 0.73 0.10 % of total N 72.98 73.34 72.23 0.42 0.72 0.11 as % of true N 78.34 78.71 77.51 0.46 0.69 0.12 Whey N % 0.099 0.096 0.101 0.002 0.80 0.21 g/d 40.8 40.9 41.7 1.4 0.79 0.69 % of total N 20.18 19.86 20.96 0.43 0.67 0.12 as % of true N 21.66 21.30 22.49 0.46 0.69 0.12 NPN % 0.0332 0.0327 0.0329 0.0004 0.37 0.66 g/d 13.9 13.9 13.6 0.30 0.66 0.65 % of total N 5.84 5.80 6.80 0.08 0.67 0.95 'Carryover p= .04l effect .479 .475 .490 0.19 0.04 Direct effect means Caπyover p= .019 effect .446 .445 .460 0.13 0.02 Direct effect means TABLE 14 COMPOSITION OF MILK FAT FROM COWS ADMINSTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Item Treatments SEM Contrast (P) Control Rumen Abomasum Control Rumen vs. vs. Abomasum Camitine 4:0 2.0 1.8 2.0 0.1 0.89 0.26 6:0 2.2 2.0 2.1 0.04 0.02 0.02 8:0 1.3 1.1 1.2 0.04 0.16 0.38 10:0 3.0 2.9 3.0 0.1 0.65 0.75 12:0 3.6 3.6 3.6 0.2 0.89 0.98 14:0 10.6 10.6 10.6 0.3 0.96 0.98 14:1 1.2 1.2 1.2 0.02 0.36 0.85 15:0 1.2 1.2 1.2 0.1 0.51 0.80 16:0 28.4 28.6 29.1 0.2 0.10 0.12 16:1 1.6 1.7 1.6 0.04 0.03 0.19 17:0 0.7 0.7 0.7 0.01 0.43 0.68 18:0 8.5 8.0 8.3 0.3 0.28 0.41 18: 1 20.6 21.2 20.0 0.6 0.96 0.26 18:2 2.8 2.8 2.7 0.1 0.57 0.24 18:3 0.5 0.7 0.5 0.2 0.56 0.38 Glycerol 12.1 12.1 12.1 0.03 0.29 0.36 TABLE 15 PRODUCTION OF FATTY ACIDS AND GYCEROL IN MILK FAT OF COWS ADMINSTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Fatty Acids Treatments SEM Contrast (P) Control Rumen Abomasum Control Rumen vs. vs. Abomasum Camitine (g/d) 4:0 29.4 28.7 28.7 1.3 0.67 0.98 6:0 32.9 29.9 30.2 0.6 0.006 0.76 8:0 18.6 17.3 17.0 0.6 0.09 0.71 10:0 44.8 44.3 42.5 1.8 0.53 0.51 12:0 53.8 54.5 51.6 2.5 0.92 0.44 14:0 157.0 161.0 151.7 4.3 0.91 0.17 14: 1 17.5 17.4 16.5 0.4 0.37 0.19 15:0 17.5 18.6 18.1 1.0 0.51 0.72 16:0 421.9 437.1 415.5 5.8 0.65 0.04 16:1 22.0 25.5 22.6 0.7 0.06 0.03 17:0 10.0 10.5 9.7 0.2 0.73 0.04 18:0 129.2 123.5 117.6 4.0 0.13 0.33 18: 1 308.9 326.4 285.1 11.8 0.83 0.05 18:2 41.0 42.6 38.4 0.5 0.40 0.0006 18:3 7.9 11.2 7.8 2.2 0.58 0.31 Glycerol 181.1 184.9 172.4 1.4 0.20 0.0007 TABLE 16 APPARENT NUTRIENT DIGESTIBILITIES FOR COWS ADMINISTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Item Treatments SEM Contrast (P) Control Rumen Abomasum Control Rumen vs. vs. Abomasum Camitine (%) Dry Matter 63.4 65.6 64.5 0.8 0.13 0.34 Crude protein 63.4 66.6 64.5 1.1 0.18 0.26 Ether extract 74.4 78.7 79.3 1.0 0.008 0.70 NDF 34.0 38.4 34.6 1.8 0.29 0.19 NDF 44.0 46.9 44.1 1.2 0.36 0.15 Hemicellulose 56.0 57.2 55.5 1.0 0.83 0.29 Cellulose 48.5 50.6 48.6 0.9 0.38 0.19 Ash 46.5 51.4 46.4 2.9 0.52 0.26 Energy 61.9 64.1 63.3 0.5 0.03 0.33 Organic matter 65.2 67.1 66.3 0.6 0.08 0.41 Soluble residue 66.6 68.1 68.3 0.9 0.26 0.89 TABLE 17 APPARENT DIGESTIBILITIES OF FATTY ACIDS FOR COWS ADMINISTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Treatments SEM Contrast (P) Fatty Acids Control Rumen Abomasum Control vs. Rumen vs. L-carnitine Abomasum 12:0 89.1 89.1 89.9 0.8 0.53 0.35 14:0 49.0 51.8 49.3 1.05 0.28 0.14 16:0 56.4 58.9 58.7 0.7 0.04 0.82 10:0 5.0 9.1 13.3 3.5 0.27 0.42 18:1 83.3 84.4 84.4 0.3 0.05 0.91 18:2 91.4 92.0 92.8 0.4 0.09 0.20 18:3 96.8 97.1 0.1 0.09 0.66 Total 18 58.1 60.3 61.6 1.2 0.10 0.49 Total 16 57.2 59.7 59.4 0.7 0.04 0.77 Total 68.9 61.3 61.3 0.8 0.05 0.98 L-Carnitine supplementation tended to increase total tract disgestabilities of dry matter and organic matter and significantly increase energy digestibility (Tables 16 and 17). This was largely attributable to the significantly increased digestibility of total fatty acids (also reflected in increased ether extract digestibility). Ruminal L- carnitine tended to increase digestibilities of neutral detergent fiber (NDF) and cellulose. Ruminal L-carnitine also tended to increase total volatile fatty acid (VFA) concentration in the mmen, suggesting an enhancement of rumen fermentation (Table 18). L-Carnitine, especially into the mmen, tended to increase proportion of propionate and decrease proportion of acetate in ruminal contents. TABLE 18 RUMINAL FERMENTATION CHARACTERISTICS FOR COWS ADMINISTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Item Treatments SEM Contrast (P) Control Rumen Abomasu Control Rumen m vs. L- vs. carnitine Abomasu m pH 5.75 5.68 5.71 0.05 0.42 0.70 NH 3 , mg/dl 10.2 9.2 9.2 0.7 0.20 0.94 Total VFA, mM 120.2 125.5 120.2 1.9 0.29 0.09 VFA, mol/100 mol Acetate 50.5 57.2 57.4 0.5 0.08 0.61 Propionate 29.7 30.4 29.8 0.4 0.05 0.35 Butyrate 10.0 9.7 10.0 0.3 0.84 0.48 Isovalerate 1.1 1.0 1.0 0.4 0.02 0.74 Valerate 1.7 1.6 1.7 0.05 0.30 0.57 Acetate: propionate 2.06 1.90 1.96 0.05 0.08 0.43 L-Carnitine tended to decrease concentration of nonesterified fatty acids (NEFA) and increase ca itine concentration of glucose in blood plasma. Abomasal L- carnitine tended to decrease cholesterol in plasma (Table 19). TABLE 19 CONCENTRATIONS OF METABOLITES IN PLASMA OF COWS ADMINISTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Item Treatment SEM Contrast (P) Control Rum Abomasu Control vs. Rumen vs. en m L-carnitine abomasum NEFA, μEq/ml 181.5 167.3 163.9 8.6 0.18 0.79 Cholesterol, mg/dl 224.4 224.6 210.0 4.7 0.27 0.07 Glucose, mg/dl 81.0 82.4 82.5 0.8 0.17 0.87 Urea N, mg/dl 14.8 13.4 13.7 0.6 0.16 0.73 Ruminal L-carnitine resulted in improvements in nitrogen retention and productive nitrogen, arising mostly from slightly improved nitrogen digestibility (Table 20). L-Carnitine resulted in increases in digestible and metabolizable energy from the diet, but this did not increase milk energy secretion, indicating that additional energy was directed was directed to body storage (Tables 21 and 22). TABLE 20 NITROGEN UTILIZATION FOR COWS ADMINISTERED WITH L-CARNITINE IN THE RUMEN OR ABOMASUM Item Treatments SEM Contrast (P) Control Rumen Abomasum Control Rumen vs. L- vs. carnitine Abomasu m N Intake, g/d 782 784 771 15 0.85 0.35 N excreted, g/d Feces' 285 260 274 9 0.14 0.32 Urine 228 228 227 10 0.99 0.93 Milk N, g/d 202 204 199 4 0.96 0.35 N absorbed, g/d 496 524 498 15 0.45 0.25 N retained, g/d 67 92 72 6 0.07 0.05 Productive N, g/d 268 296 271 8 0.17 0.06 N, % of Intake Feces 36.6 33.5 35.5 1.1 0.18 0.25 Urine 29.3 29.0 29.5 0.9 0.98 0.75 Milk 2 25.9 26.3 25.7 0.3 0.76 0.15 Retained 8.2 11.2 9.3 0.7 0.06 0.11 Productive 34.2 37.5 35.0 0.9 0.09 0.09 N, % of absorbed Urine 46.5 43.7 45.7 1.1 0.23 0.23 Milk 40.8 39.7 40.1 0.8 0.40 0.71 Retained 12.7 16.6 14.1 1.2 0.11 0.18 Productive 53.6 56.3 54.3 1.1 0.23 0.23 'Carryover effect ^= .08 Direct effect means 263.7 247.4 307.9 0.49 0.85 Carryover effect p = Λ0 Direct effect means 25.8 27.1 24.8 0.72 0.82 TABLE 21 ENERGY UTILIZATION OF COWS ADMINISTERED WITH L-CARNITINE INTO THE RUMEN OF ABOMASUM Item Treatments SEM Contrast (P) Control Rumen Abomasum Control Rumen vs. L- vs. carnitin Abomas e um (Mcal/d) Intake energy 119.0 119.2 118.0 2.7 0.91 0.78 Fecal energy 45.4 42.7 43.3 0.9 0.08 0.65 Digestible energy 73.6 76.5 74.7 2.1 0.46 0.57 Urinary energy 4.2 4.4 4.7 0.2 0.19 0.41 Gaseous energy 5.6 5.8 5.6 0.2 0.76 0.56 Metabolizable 63.8 66.3 64.4 1.8 0.51 0.48 energy Maintenance energy' 15.7 15.6 15.5 0.1 0.21 0.32 Metabolizable 48.1 50.7 48.9 1.7 0.47 0.49 energy above maintenance Milk energy 29.1 28.8 28.3 0.3 0.18 0.33 Body weight 2 577 574 570 3 0.22 0.32 'Carryover effect p= 0.01 Direct effect means 15.8 15.5 15.4 0.002 0.11 Carryover effect p= 0.01 Direct effect means 584 571 566 0.002 0.12 TABLE 22 ENERGY PARTITIONING IN COWS ADMINISTERED WITH L-CARNITINE INTO THE RUMEN OR ABOMASUM Item Treatments SEM Contrast (P) Control Rumen Abomasu Control Rumen m vs. L- vs. carnitine Abomas um (% of gross energy intake) Fecal energy 38.1 35.9 36.7 0.6 0.03 0.33 Urinary energy 3.5 3.7 4.0 0.2 0.13 0.17 Gaseous energy 1 4.7 4.9 4.8 0.1 0.33 0.31 Metabolizable energy 53.6 55.6 54.5 0.4 0.03 0.14 (ME) Metabolizable energy 40.4 42.3 41.3 0.6 0.11 0.29 above maintenace Milk energy 24.7 24.5 24.0 6 0.64 0.60 Crude efficiency 2 - 3 % 64.2 58.5 58.4 2.0 0.32 0.99 'Calculated from regression equation of Moe and Tyrrell (1979). 2 Milk energy /ME above maintenance Carryover effect p= 0.0497 Direct effect means 62.0 62.2 53.9 0.15 0.03

Claims: We claim: 1. A method for increasing the growth rate of mminants which comprises administering orally to the ruminant an effective amount of camitine. 2. The method of claim 1 wherein the camitine is combined with feed or water and said combination is fed to said ruminant. 3. The method of claim 1 wherein the ruminant is beef cattle, dairy cattle, swine or a ram. 4. The method of claim 1 wherein the camitine is L-carnitine or a salt thereof. 5. The method of claim 1 wherein the effective amount of ca itine is from about 125 mg per head per day to about 20 grams per head per day . 6. The method of claim 1 wherein said mminants are dairy cattle and the effective amount of ca itine is about 5 grams per head per day. 7. The method of claim 1 wherein said mminants are beef cattle and the effective amount of camitine is about 2 grams per head per day. 8. A method to facilitate the partitioning of milk components in a lactating ruminant which comprises administering orally to the ruminant an effective amount of camitine. 9. The method of claim 8 wherein the camitine is combined with feed or water and said combination is fed to said ruminant. 10. The method of claim 8 wherein the ruminant is dairy cattle or a goat. 11. The method of claim 8 wherein the camitine is L-carnitine. 12. The method of claim 8 wherein the effective amount of camitine is from about 125 mg per head per day to about 20 grams per head per day . 13. The method of claim 12 wherein said ruminants are dairy cattle and the effective amount of camitine is about 5 grams per head per day. 14. The method of claim 12 wherein said ruminants are beef cattle and the effective amount of camitine is about 2 grams per head per day. 15. A feed formulation for mminants comprising between 125 mg and 20 grams of camitine per head per day. 16. The formulation of claim 15 which is high in forage or roughage. 17. The formulation of claim 15 wherein the camitine is L-carnitine or a salt thereof.

Inventors: BLUM STEVEN ALLEN, HILL GARY MARTIN, NEWTON GEORGE LARRY, BLUM, STEVEN, ALLEN, HILL, GARY, MARTIN, NEWTON, GEORGE, LARRY
Applicants: BLUM STEVEN ALLEN, HILL GARY MARTIN, LONZA AG, NEWTON GEORGE LARRY, UNIV GEORGIA, BLUM, STEVEN, ALLEN, HILL, GARY, MARTIN, LONZA INC., NEWTON, GEORGE, LARRY, UNIVERSITY OF GEORGIA RESEARCH FOUNDATION
Application year: 1995
Main classification: A23K1
IPC codes: A23K1, A61K31