jUN 14 1955


Animal Husbandry Mimeograph January, 1954
Series No. 6- 7-4

UNIVERSITY OF FLORIDA
AGRICULTURAL EXPERIMENT STATION
WILLARD M. FIFIEID, Director
GAINESVILLE, FLORIDA


THE INFLUENCE OF SUBCUTANEOUS IMPLANTATION OF BACITRACIN
AND AUREOMYCIN PELLETS ON THE GROWTH AND
SURVIVAL OF SUCKLING PIGS

By

H. D. WALLACE, JOHN MCKIGNEY and LARRY GILLESPIE


Numerous experiments have demonstrated that antibiotics stimulate

the growth of growing-fattening swine. During the past year much in-

terest has been centered on the possibility of decreasing suckling pig

losses and increasing weaning weights by the subcutaneous administra-

tion of antibiotic pellets at birth. This study was undertaken to

determine the effect of bacitracin and aureomycin pellet implants on

the growth and survival of suckling pigs reared under practical farm

conditions.


Experimental Procedure


Selected pigs from 28 litters were divided at birth into con-

trol and experimental groups. An equal number of pigs from each litter

were implanted and held as controls. The pigs were carefully allotted

according to birth weights. The experiments included pigs from purebred

Duroc, Hampshire and Spotted Poland China sows and gilts which farrowed

in the fall of 1952 and spring of 1953. All litters were raised on

good pasture and had access to a complete creep mixture free of anti-

biotic.









All implantations were made on the first or second day of life

and the pellets were inserted under the skin at the base of the ear

with a small trocar device. The bacitracin pellets contained 1000

units of antibiotic and the aureomycin HCL pellets contained 20 mg.


Results and Discussion


Results of the study are summarized in Table I. The data were

treated statistically by the use of Student's "t' formula.

In the bacitracin experiment the percent survival to weaning

favored slightly the control group. However, survival was very high

in both groups and no real difference was apparent. Average birth

weights were almost identical for the treated and untreated pigs and

at the end of four weeks they remained practically the same. Again

at 56 days the weaning weights for the two groups of pigs were very

similar.

The aureomycin experiment gave much the same results. Survival

to weaning of implanted and control groups was identical, and again

was very high. Four week weights and weaning weights favored the im-

planted pigs by a small margin, but the differences were not statis-

tically significant. At four weeks the implanted pigs averaged 0.4

lb. heavier and at weaning 0.6 lb. heavier.

The results of these experiments appear to be in agreement with

the majority of the tests conducted, which indicate that under con-

ditions commonly prevailing in Experiment Station swine herds that

subcutaneously implanted antibiotic pellets are of little or no bene-

fit to suckling pigs. Neither have they been found to be detrimental

in any way.




























Initial nu
pigs

Final numl
pigs

Percent su
weaning

Average bi
pounds

4 weeks we
pounds

Weaning we
days) po


TABLE I

The Effect of Bacitracin and Aureomycin Implants
on the Growth and Survival of
Suckling Pigs


Experiment I Expe
(Bacitracin) (Aur

Control Treated Control

imber of 69 69 46


er of 65 64 h3


irvival to 94.2 92.8 93.5


.rth weight, 3.07 3.06 2.94


iight, 14.4 14.6 13.7


tight, (56 32.6 32.9 30.1
>unds


riment II
eomycin)

Treated

46


h3


93.5


2.87


l.1


30.7









Summary


Two hundred and thirty pigs from 28 litters were used in two

separate experiments to study the influence of bacitracin and aureo-

mycin-HCL pellet implants on growth and survival of nursing pigs. In

these tests there was no significant effect of either antibiotic on

4 week weights, 56 day weights, or survival from birth to weaning.

































MW/ar
Animal Husbandry
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