Animal Molecular Breeding 2016, Vol.6, No.1, 1
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attributable to anomalous fetuses in farm animals
forms 30% of losses (Samuel et al., 2013)
Olsen and Miller, 1958; Bancrroft and Gamble, 2007
suggested that bovine congenital fetal anasarca could
arise from chromosomal aneuploidy characterized by
late gestation abortions (Coates et al., 1988; Tickle,
2003). As a component of hydrops fetalis (Machado
et al
., 2002), and a heritable condition common in
Ayrshire and Swedish lowland breeds of cattle but has
been reported in Humans (Karen and Melisa, 2011).
6 Discussions
Conjoined twinning; Based on body region of
connection are classified as craniopagus, cephalopagus,
thoracopagus, omphalopagus, pyopagus, ischiopagus
and rachipagus (Duhamel, 1966) had been reported to
be an outcome of fission-fusion theory with a higher
probability of fission failure (Spiers et al., 2014;
Lanteri et al., 2012).
About 2% of human infants are born with a readily
observable anatomical abnormality (Bowers, 2011)
including missing limbs and occurs as disruptions to
genetic instructions (Devanathan et al., 1990; Samuel
et al., 2015). Co-option (recruitment) of existing genes
and pathways for new functions is a fundamental
mechanism for creating new phenotypes (Binanti and
Riccaboni, 2011), Duplication and divergence at gene
level may allow these to assume divergent functions
(Szczerbal et al, 2006). Stability defects in the
expressivity of genes (Szczerbal et al, 2006)
responsible for the development of limbs could be
incriminated in the pathogenesis of this type of
phocomelia observed (Smolec et al., 2011; Olopade et
al., 2011). Findings on the present cases are consistent
with previous reports in ewes, buffaloes and Does
(Milton et al., 1989, Devanathan et al., 1990 and Laiju
et al., 2012).
Some birth defects are produced by mutant genes or
chromosomes, while others by toxic, viral,
environmental or a combination of these factors that
impede development (Kaufman, 2004; Devanathan et
al., 1990). Neural crest cells are precursors of pigment
cells (Saperstein, 2002) which seem deficient in the
areas around the skin covering the undeveloped limb
suggests the likelihood of commencement of such
impairments at gastrulation and organization stage in
the embryo (Bowers, 2011).
Exogenous disruptors including chemicals, viruses,
radiations hyperthermia and toxic plants may act as
substrate in allometric growth impairments of body
parts in in-born developmental errors (Newth, 1978;
Conlon and Raff, 1999). Phocomelia has prior been
reported to be associated with ingestion of
pthalidomides in the first trimester of gestation
(Gilbert, 2006). Phytoteratogens, in a similar manner
by placental crossing causes deleterious effects
through embryonic demise and could be species
specific (Knight and Walter, 2012) but milder in late
embryonic life. Veratrum californicum (Jervine,
cyclospermine, swainsonine and anagyrine an alkaloid
of quinolizidine) inhibit cholesterol synthesis and as
well incapacitates Sonic hedgehog functionality
leading to cyclopia and arthrogryposis in lambs and
goats (Binns et al., 1972; Hiraga and Dennis, 1993).
Inorganic crop fetilizers applied to forages fed to
pregnant animals may be incriminated. Observed
developmental errors demonstrated by phenotypic
incompetence occasioned by anatomic deformities of
tissues/organs may compromise viability (Dyce et al.,
2002). Two separate reports, Czarnecki (1976)
globossus amorphous fetus in cattle, Nottidge et
al.,(2007)
cranio-thoracopagus
(Monocephalus
thoracopagus tetrabrachius) in dogs, inherited
abnormalities has been attributed to environmental
factors such as extreme temperatures, consumption of
toxic substances such as herbicides at onset of
planting/breeding seasons and long period of drought.
Precautionary mechanisms to serve as preventive
measures in the etiology of such mutilating conditions
should be directed towards genetic engineering and
safe farm practice with prompt report of occurrences
for investigation of probable etiology, migrations of
herdsmen with breeding stocks should be
discouraged/provided transit route camps with
adequate feed supplies. Furthermore, in abnormal
weather events with sustained daily mean temperature
departures of 1.9-2.9˚C (NIMET, 2010) for over two
months and prolonged dry period supplemental
feeding of pregnant does may discourage the use of
alternative diets through which unwholesome plants
are browsed. Feeding of stored feed rations often
moldy should be discouraged in breeding seasons
despite preponderance of low grade dietary
alternatives (Terje et el., 1996) in inter-tropical
discontinuities and resultant fluctuations dry spell
