NL8400848A - METHOD FOR IMPROVING MILK PRODUCTION IN MILK-GIVING Ruminants. - Google Patents

Description

s - * VO 6141

A method for improving milk production in lactating ruminants.

The invention relates to a method for increasing milk production in lactating ruminants such as dairy cattle, goats and sheep.

More particularly, the invention relates to a method for increasing milk production in lactating ruminants by feeding it orally about 0.04 mg to 0.33 mg and preferably 0.08 mg to 0.25 during the lactation period mg avoparcine or a salt or complex thereof per kg body weight of the animal per day. The antibiotic avoparcine is also sometimes referred to as the anti-biotic Av290 and is generally prepared by a fermentation process.

Avoparcine (AV29Q) essentially consists of two water-soluble glycopeptides, hereinafter referred to as the α and β components of avoparcine. These components are discussed in the following publications: W.J. McGahren, et al., "Structure of Avoparcin Components", 15 Journal of the American Chemical Society, 102, 1671 (1980) and "Avoparcin", Journal of the American Chemical Society, 101, 2237 (1979).

The structure of avoparcin (AV29Q) is shown in Figure 1. The component has the configuration shown in Figure 1, wherein R 'and R each represent hydrogen, and the β component is equal to it with the exception that R' is hydrogen and R represents chlorine.

In accordance with the present invention, avoparcine is administered orally to lactating ruminants in or together with their feed in the form of a feed premix or concentrate. It can also be presented in the form of a top dressing for the fodder or administered in a slow-release bolus designed to continuously provide the animal with the desired amount of antibiotic during the lactation period.

The antibiotic can be used in its substantially pure crystalline form or can be used as a pharmaceutically acceptable salt such as the hydrochloride salt of the antibiotic or as an antibiotic complex such as the alkylated sulfate, syn tan or tru tan complex of avoparcin. In the design of the present invention, it has also been found that the antibiotic avoparcin is effective for increasing milk production in lactating ruminants when the antibiotic is administered orally in any of the above forms but associated with the dried solids from the entire crop of fermentation mass in which it was produced.

Administration of about 0.04 mg to 0.33 mg avoparcine per kg animal body weight per day (ie 0.04-0.33 mg / kg body weight per day) amounts to about 24-200 mg / kg each per day for lactating dairy cattle and about 2.4 mg to 25 mg per kg each per day for lactating goats or sheep.

When the antibiotic is administered in the form of a salt or complex, the amount of salt or complex used should, of course, be adjusted to obtain the aforementioned dosage level of avoparcine.

Although avoparcine is an important commercially available antibiotic, used in the feed of meat-processing animals to increase its growth rate, it has been found that when this antibiotic is administered to lactating dairy cattle in the recommended dosage levels for growth promotion in beef cattle, milk production and / or milk quality is measurably reduced.

Therefore, the concept - that all glycopeptides including actoplanin, avoparcin A-35512, vancomycin, ristocelne A-477, K-288, and .AM-374 are essentially equivalent as the milk production enhancers for lactating dairy cattle, as suggested in the. British Patent Application No. 2,096,895A, published October 27, 1982, is incorrect and / or misleading, at least as far as avoparcine is included in the glycopeptides indicated.

As will be demonstrated hereinafter, administration of avoparcine to lactating dairy cattle, at dosage levels of about 50 mg and 150 mg each per day, leads to. increased milk production and / or milk quality; administration of avoparcine to lactating dairy cattle in an amount of 300 mg per body weight per day up to. 600 mg per body weight per day, on the other hand, leads to a decrease in the milk production and / or milk quality of the treated animals.

The present invention is further illustrated by the examples below.

8400848 #. * 3

Example X.

Evaluation of avoparcine for increasing milk production and / or the quality of milk from dairy cattle

The experimental design 5 used in this evaluation consisted of three periods. Period I was a 28 day pre-experimental period in which all cows in the dairy herd were noted and a choice of suitable cows was made for the trial. Period II consisted of 28 days in which the avoparcin treatments were performed, and period III was formed by a subsequent 28 day post-10 avoparcin treatment period. The entire experiment took place over a 3-month period.

A total of 28 Frisian dairy cows were selected from a lactating herd of more than 60 animals. Each cow had calved for a minimum of 6 and no less than 22 weeks and at that time had 15 daily milk production in the range of 17 - 32 liters. Four weighed treatment groups were carefully formulated to each contain animals paired with respect to milk production and lactation stage. Each weighed group was then randomly assigned to one of four experimental treatments. Group Ά did not receive avoparcin 20 and acted as an untreated control group. Groups B, C and D received 50, 150 and 300 mg avoparcine each per day over a continuous 28-day period, respectively. Each of the cows included in the experiments received their portion of avoparcine in one meal when milking in the afternoon. Carefully weighed amounts of avoparcine O) 25 (ie 1g, 3g and 6g AVOTAN ^ 50, avoparcine, the 5% active ingredient premix for treatments B, C and D, respectively) were included in batches and 250g of a tasty concentrate on base of corn.

At the start of an investigation, the cows were standing on 30 grass. During the first week of period II, they were fully converted to the basic winter ration, which consisted of 35 kg of fresh silage estimated to provide maintenance only. u A weighed out dairy concentrate (180 g CP / kg) was given for all milk produced at an amount of 0.4 kg per liter during the experiment.

Milk yields were recorded, and milk samples were taken on four occasions during pre-experimental period I and daily during the first three days of feeding. taken avoparcine. Then milk yields and samples were determined every other day until the end of the entire experimental period. The milk yields and samples were maintained periodically for the following immediately after the end of feeding with avoparcine for 28 days. (period III).

The milk samples taken were collected and prepared for both morning (5.30 am) and evening (3.30 pm) milking. every day. Analysis of the composition on butterfat, protein and lactose were performed according to standard automated techniques.

During the course of the trial, five cows required antibiotic therapy for mastitis. Two cows were severely affected and were withdrawn from the study. As a result, final data refer to 7 cows for. each of groups A and D 15 and six cows for each of groups B and C.

Tables, A and B provide details regarding the average daily yields. and ... butterfat contents of the four treatment groups as determined during the trial. Table C contains details regarding one. self-evident consideration of those data where. average milk yields and butterfat contents per group of the cows during the pretreatment, during the 28 days of feeding with avoparcine, and. likewise .during..the 28 days. after. the end of the avoparcin treatment are presented. The groups showed a strong agreement during the pretreatment phase; however, after the treatment with avoparcine, it was clear that the untreated controls, group A, and the group that. Group D received 300 mg of avoparcine per day - a significantly larger decrease in milk production and some decrease in butterfat content. showed. groups B and C. The decrease in milk production .in. in particular, continued in these 30 groups XA and D during the 28 days after the end of the treatment. During the period in which ... with. avoparcin was fed (II), both groups B and C showed a slower decrease in yield per day than the untreated control group. When the total decrease in yield was investigated (by averaging the milk production during both the avoparcin feeding period (II) and the 28 days after the end of this period III) and (comparing these averages with the average milk yields obtained in period 8400848 tz 5 (I)), could it be observed that the decrease in total milk yields obtained with group B 50 mg per piece per day? and group C was 150 mg each per day, was only about a quarter to half of the decrease obtained with the untreated controls, groups A and D, treated with avo-parcine at 300 mg per piece by day. In fact, the greatest decreases in both milk production and butterfat content were observed in the group receiving 300 mg each per day.

Table C gives mean values per group of milk production and butterfat immediately prior to treatment, during the last two weeks of avoparcine treatment, and during the last two weeks of the period at the end of treatment with avoparcine followed.

The data of Tables A and C are also shown graphically, in Figure 2.

TABLE A

Milk production during the 28-day pre-treatment period I.

The average milk yield (liters / day) of untreated cows, classified in group A of untreated controls, 20 group B of 50 mg per day avoparcine, group C of 150 mg per day avoparcine, or group D of 300 mg each avoparcine per day.

Group A_ B _C_ D_ untreated 50 m »/ d 150 m» / a 300 mg / d milk-on-milk-on-milk-on-milk yield 25 yield yield yield yield day liters / day liters / day liters / day liters / day -28 26, 1 26.3. 24.3 24.5 '- 9 22.9 23.0 22.7 23.0 - 1 22.0 23.1 22.6 23.0 30 21.7 23.0 22.4 22.1 average milk yield (liters / day) 23.18 23., 85 23.13 23.15 '8400348 6 * * TABLE A (Continued)

Milk production in period II during 28 days of treatment

The average milk yield (liters / day) of untreated group A cows and cows that received 50 mg each avo-5 parein per day group B, 150 mg each per day received avoparcine group C or 300 mg each avoparcine received group D, in a 28 day treatment period.

Group A 13 C D_ untreated 50 mg / d 150 mg / d 300 mg / d 10 milk yield milk yield milk yield milk yield 'day liters / day liters / day liters / day liters / day 1 21.8 23.8 22.1 22.2 2 21.8 23.9 23.1 21.6 3 21.9 24.9 21.9 22.3 15 5 21.3 25.3 22.7 20.1 7 23.1 25.7 24.8 22.7 9 22.7 '26, 3 24.5 .21.5 11 22.6 26.6 24.4 23.7 13 22.6 25.8 24.3 23.1 20 15 21.2 25 .0 22.1 21.0 17 20.7 25.2 20.3 21.3 19 19.5 25.2 22.4 20.3 21 20.0 24.4 23.5 20.1 23 19, 0 22.5 22.4 18.9 25 25 19.4 22.4 21.2 18.7 28 19.5 22.7 21.4 18.7 average milk yield (liters / day) 21.14 24.85 22.74 21.08 8400848

£ V

7 TABLE A (Continued)

Milk production in period III for 28 days after treatment

The average milk yield (liters / day) of untreated group A cows and cows treated in period II of this evaluation with 50 g each avoparcine group B per day, 150 mg each avoparcine group C per day, or 300 mg each per day avoparcine group D.

Group A B_ C D_ untreated 50 mg / d '150 mg / d 300 mg / d 10 milk yield milk yield milk yield.milk yield day liters / day liters / day liters / day liters / ___ day + 2 18.9 22.3 20.7 19.4 15 + 4 18.8 22.3 20.2 19.1 + 7 19.3 22.9 21.3 19.1 + 9 18.3 21.9 20.3 18.5 +11 18, 9. 20.4 19.7 17.4 +14 19.5 21.0 20.4 17.6 20 +16 19.4 20.1 20.3 17.3 +18 18.5 20.1 18.6 17 , 1 +20 18.3 20.4 18.8 16.3 +22 18.5 19.9 20.4 15.5 +25 18.0 20.1 19.8 15.6 25 +28 18.2 20.0 19.9 15.7 average milk yield liters / day) 18.72 20.95. 20.03 17.38 Groups B and C were reduced to nes cows in period III.

TABLE B

The percentage butterfat content of milk samples in period I from cows during the 28 day pretreatment

The mean butterfat percentage of milk samples from 35 untreated cows, classified in group A of the untreated controls, group B of 50 mg per day avoparcine, group C of 150 mg per day avoparcine, and group D of 300 mg per piece per day avo- 0 4 9 3 3 4 8- 8 i

f V

pareine.

Group A £ C D

untreated 50 mg / d 150 mg / d 300 mg / d day% butterfat% butterfat% butterfat% butterfat 5 -28 4.01 3.84 3.82 4.11 - 9 3.89 3.78 3.71 3, 97 - 1 3.71 3.72 3.80 3.82 0 3.82 3.80 3.80 3.71 average 10 percent butterfat 3.86 3.79 3.78 3.90 TABLE B (Continued) - Percentage of butterfat from milk samples in period II of cows during 28 days of treatment 15 The average butterfat percentage of milk samples from cows that either received no treatment group A or 50 mg each per day 5 avoparcine received group B, 150 mg per day avoparcine received group C and 300 mg each per day avoparcin received group D in 28 days of treatment.

20 Group AB _C I) untreated 50 mg / d 150 mg / d 300 mg / d day% butterfat% butterfat% butterfat% butter _____ ___________ _ _ fat 1 3.79 3.78 3.78 3.87 2 3, 75 3.65 3.21 3.70 25- 3 3.71 3.83 3.54 3.21 5 3.54 3.80 3.37 3-57

7 3.30 3.84 3.40 3r4O

9 3.27 3.97 3.58 3.42 11 3.37 3.84 3.63 3.85 30 13 3.25 3.79 3.44 3.25 15 3.47 3.72 3.80 3.53 17 3.40 3.54. 3.59 3.50 19 3.45 3.60 3.30 3.38 21 3.57 3.71 3.41 3.35 35 23 3.58 3.47 .3.58 3.38 8 n 0 9 4 8 9 TABLE · B (Continued) ««

Group A B_ C _D

untreated 50 mg / d 150 mg / d 300 mg / d day% butterfat% butterfat% butterfat% butterfat 25 4.05 3.70 3.78 3.66 5 28 4.06 3.76 3.67 3.66 average percentage of butterfat 3.57 3.73 3.54 3.51 TABLE B (Continued) 10 Percentage of butterfat from milk samples in period III of cows during the 28 day post-treatment

The average butterfat percentage of milk samples of. untreated cows from group A and cows treated for a period XI of this evaluation were treated with 50 mg per day avoparcine group B, 150 mg per day per avoparcine group C, and 300 mg per day avoparcine group D .

s

Group AB c £ untreated 50 mg / d 150 mg / d '300 mg / d day% butterfat% butterfat% butterfat% butterfat 20 + 2 3.94 3.50 3.86 3.91 + 4 3.52 3.80 3.64 3.75 + 7 3.57 3.72 3.55 3.61 +9 3.71 .3.74 3.66 3.76 +11 3.71 3.80 3.86 3.72 25 +14 3.84 3.81 3.86 3.73 +16 3.91 3.77 3.79 3.71 +18 3.93 3.87 3.74. 3.70 +20 3.84 3.43 3.52 3.65 +22 3.75 4.00 3.63 4.03 30 +25 3.99 3.96 3.78 3.82 +28 3 .82 3.98 3.84 3.77 average percentage of butterfat 3.79 3.78 3.72 3.76 8400348

TABLE · C

* * 10

The mean milk yield and percentage butterfat content of milk samples for periods I, XI, III, for untreated group A cows and cows treated with 50 mg each avoparcine group B, 150 mg each etuk; per day avoparcine group C, 5 and 300 mg each per day avoparcine group'D.

Period Group Average milk Average yield (liters / day) percentage of butter _ _ fat pre-treatment) A 23.18 3.86 10 I) B 23.85 3.79) C 23.13 3.78) D 23 , 3.90 treatment) A 21.14 3.57 II) B 24.85 3.73 15. ) C 22.74 3.54) D 21.08 3.51 aftertreatment) A 18.72 3.79 III) B 20.95 3.78) C 20.03 3.72 20) D 17.38 3, 76 8400848

II

-ί ® φ SS1 I Ό P ® ο »i — i> -y

O '<D C

e '2 I g

• ho a R

Η Ή 5 ft ai 6 c 5 «σ ®," Ϊ ft ·

ö O »-U AS -M

ns m f. vomin cN Φ o ^ 1/1 t! r <G O 'O' N Ol i 'O' Φ> ft o fi cn (D | rt £ | Tt * 0 M ^ ^ * ·> (DO ηο ^ -ιτη ft Φ ΟΟΟΌ

^ (1) -iJ

© Η Φ Λ Ö3 S 0 1— (η ε ft st 2- ° Ή H (0 0® * d ,, «CJ4-P 1-¾ Ü) <H <-4 · Η, ® 2- G Ό nC Φ Ή Ο Λ as ο e -> -H S4 m φ Sf ft Φ 01 4J O '

- »03 C

O 'G Ti,.

ft Ο Η I ΰ o s ® I i ‘2.

> X O X O ft H

S-) 1-f C ft Ή 2 .., ΦΦβ®Η -ft ® + sgi ΗΦΗ ^ ν OO '- φ Q | HS' cm O 00 η Λ axis H _ - C Λ ® H (Ö QO 'n N _, + J -Η ^ as axis OJJ Ό * · «· -— Ό C co r- · vö o

> c ft 03 + \ O 'CM f O'> -j ® G m m rZ

out> »· η nn · η © u Φ η η η n Φ + OCHM 13¾¾ * J ΌΦΗΦ 5 ® o -4 Η -HU -U -¾ ftTj ►qmw £ Λ ® Ή SJJ ^ JC © ft © ft © © ®

ΗΦΦ C3 Ο Ό w C5> A

σ> Ό «+> 0 Φ 1-i <> u u ®

Eh ® ft +1 m.

OO '* ne +> • 5 - g • P iH IIO'> © © Ü Ο Λ ft Λ Ό Η -Η Ό Φ c © n \ ο ό η “ΐ + J„ _ _ G® ε © © _i ® —Ι - <ο g ® ® 2 φλ -cum * -> · «* Λ ® ^ ^ ® Φ φ® tnmmrn _ © - ~ ^ 43 J3> 0-U4J CM CM CM CM <0 O '' H (Π Ρ1 Λ π η Η 03 Ή - * Η Λ θ '· Φ θ' ft. © Ü, 3 C03OC- '53¾ ®> Ό ω S © ο Μ ft U Η © Τ * η Λ £ Η Η

ftO * ®A® ® ® J

Ο C U Ο Ό C5 ft ft 44 Ή ιΗ τ— {0) Φ ε 2

C

® shaft. - - *

Ό X

r-t Φ Φ Λ ίο -η ® -.

Ό Ο C

-Η Ο Ή Ε> θ 'Ο θ' O '- * C SH ιβ 9 Η' hS, V- ΟΟΟΟ 0 0-00 φ ο ο ϋ ιηιπ-ο m tno Ό © Ό> D fin f * n Ό C Φ -Μ GO <8 03 <β -Η Λ 4-1 \> U Φ Φ θ '® «ε ε O' ft

C

• Η G

44 Ή • η

-Η G

ft Φ Φ ft ft Μ Ο 0 <ffl ϋ Ο row ffl Ο Λ φ Μ Μ> θ 'Ο 8 4 "0 8 4 8 12

Example II

Evaluation of the effects of 600 mg per piece avoparcine on the milk product in lactating Frisian dairy cows

Ten Frisian dairy cows were selected from a herd of more than 60 pieces in such a way that each cow had calved for 18 to 23 weeks and at that time had a daily milk production in the range of 13 to 18 liters. The basic diet consisted of 35 kg of fresh chew food calculated to provide maintenance only. A weighed dairy concentrate feed was given for all milk produced in an amount of 0.4 kg per liter of milk.

Each of the experimental cows received 600 mg of avoparcine in a meal per day for each of three consecutive days (one, two, and three). Weighed aliquots of 600 mg of avoparcine (i.e., 12 g of AVOTAN® avoparcine 50, the 5% active ingredient premix) were included in 15 batches of 500 g of a tasty corn-based concentrate. The 0.5 kg avoparcine-containing concentrate replaced 0.5 kg of the normal concentrate with each feeding.

Milk yields were recorded and milk samples taken during the -avoparcine feeding period (days one, two, and three) as well as -20 on days four, five, seven, and ten Xd, i.e. one, two, four, and ancillary days after avoparcin administration was discontinued). Average milk yields from 52 other cows in the herd were also taken as controls during the experimental period.

The milk samples were analyzed according to standard methods for butterfat, protein, lactose and the total solids content.

Only one cow on one occasion refused any of the avoparcine-containing concentrate offered to him. On all other occasions, the material contained in the 0.5 kg concentrate was well consumed. Undesirable effects were never observed in the cows participating in the experiment.

The average milk yield of the ten cows given avoparcine decreased significantly from 15.1 kg per day on day one (ie, two days before feeding avoparcine) to 12.7 kg per day on day-ten of the experiment . This can be compared to the average milk yield of 52 control cows which remained fairly constant at about 16.5 kg per day (see Table D).

8400848 i 13 Φ u a a © o> ra c Ό ©

Cn ra Φ © η- vo Ό Μ O * ~

Ct M CM VO

φ · φ -ι-t · "'f O' O '^ ί 0 -q> ©

Ot · Ό

Ο * 0 CD CN

: 0 - ~

© XX fi OI VO

-Η Ή <

Si © 0 -c

-H CO

KJ U

> nj O '"M1 Q.« · * ·

χ Ο ιΛ ΟΙ VO

rq> * - <—v © ra

τι -C

-Η Φ Λ Φ _ 0 »C \

(B »VO

c ® rr cm ^ -Η -Η Ή Ό Ö tQ **

Si 18 Φ ft Ό: °% 1 S ^ ** m m - * · ** j O '© -'i vo E Ό * - · - * - Η - * Η * O i-l ffl Ο Φ

VO M

«Rf Φ

O> 0 O 'CD

Pi -1 CM - ^ Ό c m ^ -rl - * Η - <c Φ c ft Φ φ Ή 0 ©

, ¾ 0 O 'VO

J4 'ίη »* ·

C X * 9 VO

© fi i-l —i Ή Φ

-PS

fi CM

<8 in _ _> or- CO * · - λ i8. tn vo O '> -if! 18

Ό X

«O 'Φ c _ ft Φ -ri O' - ·. i. ; -. 0¾. .

Si - <»*, - Ό 'λ t tn vo X Οι -Ί-Ι" -I. - - o X ft m φ O' S ft - i— * q q O 'O' φ φ Φ <8 q 18

Si Ό SO® Ό _

ij ft ft · Η C

a φ Si n φ n © 0> 0 φ φ Ο φι-1 x Ό ft ft A ft 2 <-l ft X _ 0 Φ. s φ O 'φ O'

S © ϋ £ A

O 'ft ft Φ φ φ Ο ft ft © A ft Si X 0 ft Ό M 18 W Si © c o> a o> x Ό q re q o c q ό ©> ©> © o -¾ U 18 Si Ü

SC O 'Λ A

© © t8 ft O ft CM

U O 'D O —4 o vn 8400848 y 14 Φ Φ O -Η • π Ό Η

Η C

S φ w -Η Φ 111 ΟΙ Ο φ ο cn m νο

CO

φ CN Π * 5i-t h «n h c O 0)

.o -H

-p

- O O O ι-t -dP

φ: C O τη Ρ »P- - <rt CT> (0 'P · * *» P * tè> η n Tf ή * ·

-O i “lO

C w φ p Φ

0 O) -P

ρ 4j c φ and p * σι m o <d 01 c (Ti cn ό Ό -u C o lo ·. »·. *, cn Φ g cu tn TT * -4 c Ή M * o

-T-4 U

0 0) + J E + 01 Φ C m m -4 co Φ + j (0 m tn r * o tn

oi> n · - · - * O

nj m m -¾1 oi -P

> C «- * 2 Φ its O) 44 f4 1—1 (Ö H (Ö 4-1" * 44 H -H in P «-n * 4-1

0 c -sr CN 10 O H

44 CO m ^

φ rt ri N * H

P? · »P -« - * Φ 01 44 H O 'üï · * - (0 0) 44

44 '\ -P 44 O

Ci cn σι <n <n> <3 0) Φ tn m Ό it P 1 0 a · n * »»> ai Ei P>, C ΓΟ O "W CN 44 Φ i-4 Φ Ή o fit K Oi Λ Φ C Φ _ 01 tö p .0 oi 4 «;„ <e 44 s ^ οι hm> osc tn tn λο p *

10 O Φ i-i. * »« .. *. C

Η · Η ö> O

44 til * "l 1" +

O Ό * H

ai -Η φ

θ 'Λ 0) 4J

(β -Η Ό ft 44 ip c o C C Φ fl IS ti 10

ΦΛ Οι o tn tn P m -P

ü H *** "» * O

p c o m tn i cm O

φ φ> »-t Ό ft ft 4? * o <0

• P Λ C

S C Φ Φ

• η φ * H in co »rn X

ΦΌΡ —tincN O i-t φ c na | - - λ · - .44 4.: φ m m C -tM. m *.

QI N c yes O 'i-1 TO. . _ * 3> - β 4J τί τ! φ C -X φ · <ρ 0) 1-4 1) 4 νρ Ο C Φ 44 44 Ο Ρ Ιφ C Ο 44 01

φ -Η ft Φ 44 01 C

Οι Ρ Ο Ε 01 „φ 44 φ -4 Φ> φ 44 φ Ρ Φ 44 φ> Ο C Φ 44 01 θ 'Ρ (0 Ή Ο) 01 (Ö φ Φ Λ Ο X (0> θ' 44 Ρ φ >

0 Φ to C C

Λ Η ft 44 C 5 Φ (Ö 0 φ <0 IÖ Φ «Ο 44> Λ ίβ θ 'Η Ο ίΰ 44 Η ·

φ 44 C Φ ΦΗ 1ÖII

Ό θ '<0> 0) (C <0 • Ο * S> P4J0 (Ö 44 · • Hi- Φ 4 4J J Ο Ό

ECO Oi-PSOO

SO «SO-H <0-P * ο c ίο q yes φ f4 x x c 8400848 .......

fi ^ 15

An examination of the composition data in Table E shows no changes in the protein and lactose content of the milk over the experimental period. However, the butterfat content shows a marked decrease, which is very evident on days five, seven and ten.

The observed decrease in total solids content (12.13% on day -1 decreasing to 11.7% on day 10) is therefore due to the reduced milk fat production and not any change in the protein or lactose production.

It is clear from the above data that the oral administration of 600 mg each per day of avoparcin to lactating cows had a pronounced and observable effect on milk production (15% reduction) and butterfat content (approximately 10% reduction). a related effect on the total solids content of the milk, (the reduction of the total solids from 15 12.1% to 11.7% would in fact be sufficient to obtain a fine of 0.3 p / 1, based on the Scottish Milk Marketing Board Compositional Quality Payments Scheme, 1981).

8400348

Claims (5)

A method of increasing milk production in lactating ruminants, wherein about 0.04 mg of hot is administered orally about 0.33 mg of avoparcine per kg of animal body weight per day. _5 2-. The method of claim 1, wherein the avoparcine is administered orally to the ruminants in an amount of about 0.08 mg to 0.25 mg avoparcine per kg animal body weight per day. The method of claim 1, wherein the ruminants 10 are selected from the group consisting of dairy cattle, sheep and goats. 4. A method for increasing the milk production in dairy-producing dairy cattle, wherein said cattle is administered orally about 25 mg to 200 mg avoparcine per piece per day. 5. A method for increasing the milk production in lactating dairy cattle, wherein said dairy cattle is orally administered avoparcine in an amount of 50 mg to 150 mg avoparcine per day. 6. A method for increasing milk production in lactating sheep and goats, wherein about 2.5 mg of 20 to 25 mg of avoparcine are administered orally per day. 8400848