| dc.description.abstract | The objective of the pig industry is to produce a
large number of healthy piglets efficiently and
economically. Thus the sow is the productive unit of
industry. The reproductive processes of the sow
include estrous cycles, ova production, copulation,
pregnancy maintenance, parturition and lactation. At
the end of the gestation period, the sow should produce
a satisfactory number of morphologically and functionally
normal piglets and nurture them to weaning age with
minimum losses. Malfunction or failure of any or a
number of these reproductive processes would affect
the' reproductive performance of the sow.
Investigations on reproductive performance and
problems in swine have been made in different parts
of the world. Very little has been done on this
subject in Kenya. This work was done to gatfler data
on reproductive performance in female pigs in Kenya.
Particular reference was given to the ability of the
sow to produce ova (ovulatory rate), litter size,
prevalence of anatomical abnormalities of the reproductive
organs, prevalence of brucpllosis, leptospirosis and
other bacterial agents which exist as conensals in
the genital tract of pigs but may cause reproductive
problems.
Data for Litter size were collected from nine
piggeries around Nairobi. All or some of the 1,092
uterine specimens collected from the two bacon
factories in Kenya were studied for ovulatory rate,
prevalence of anatomical abnormalities; cystic
ovarian follicles, presence of bacterial agents and
embryonic mortality. In addition to these, attempts
were made to detect antibodies against ~la and
Leptospira using 500 blood samples. The serum
agglutination and Rose Bengal plate tests were used
in the case of Brucella and the microagglutination test
in the case of Leptospira.
*' The mean litter size was 10.4 ± 2.0 and mean
~
number weaned was 8.6 ± 2.5 piglets per litter. 17.1%
of the piglets born died during the preweaning
period but the causes of death were not easily
obtainable. The mean ovulatory rates were 11.4 ± 2.5~
anq 9.2 for gilts and sows respectively. Cystic
ovarian follicles were observed in 2.7% of the specimens.
A 25% embryonic loss was observed in the gravid
uterine specimens. About 65% of the fetuses were
in the anterior presentation. Malformations of the
reproductive organs were found in 27.9% of the animals.
Escherichia coli, Streptococci, Staphylococci and
corynebacteria were the bacteria isolated from the
reproductive tracts. Antibody titres against
Brucella and Leptospira were low. Two herds were
positive for brucellosis anq one for leptospirosis.
Results from the abattoir specimens and litter
size data from farms indicates that the ovulatory
* ± - Stau.tiard deviation (S.D.)
rate of gilts: embryonic mortality; litter size; piglet
mortality: and incidence of malformations of the
reproductive organs were similar to those recorded in
other countries. The incidence of cystic ovarian follicles
was very low compared to results from other countries.
It was concluded from this work that all these
factors had no adverse effect on the reproductive
performance of female pigs in Kenya.
Antibody titres against Brucella and Lept,ospira
were low. It was therefore concluded that infection with
these organisms may be rare in female pigs in Kenya.
Further research on other reproductive parameters
such as age at first service, weaning-to-service
interval, returns to service and number of litters
per sow per year is required to gauge overall
reproductive performance of female pigs in Kenya.
Continuous research is necessary in order to detect
reproductive failures when they occur so that they can
be corrected. | en |
