Daniel two species and six subspecies (Grimont and

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            Daniel Elmer Salmon and Theobald
Smith first identified Salmonella
in1885 from a hog cholera infected pig. In1892, Klein identified fowl typhoid
from a adult bird. Later, in 1900 a French veterinarian bacteriologist Joseph Leon Marcel Lignieres proposed the
genus name Salmonella in the honor of
D. E Salmon. In 1892, Loeffler first isolated S Typhimurium. Jones used agglutination test to identify the
carriers of Salmonella Pullorum (Tessari et al.,

 Salmonella belongs
to the Enterobacteriaceae family, consisting of two species and six subspecies
(Grimont and Weil, 2007; Marlony et al., 2011). S enterica and
S bongori are the two species
belonging to the Salmonella genus (Tindall et al., 2005). According to the biochemical and genomic
modifications, S. enterica is subdivided into six subspecies enterica,
salamae, arizonae, diarizonae, houtenae, and indica (Brenner et al., 2000). Over 2500
serotypes, 80 serotypes are involved in human and animal infection (de-Freitas et al., 2010). Based
on the serovars, the genome size of Salmonella
is varying from 4460 to 4857 Kb (Andino and
Hanning, 2015). More than 95. 5 per cent Salmonella strains isolated from human and other warm blooded
animals are under enterica subspecices (Le minor, 1981).
World Health Organization (WHO) Collaborating Centre for Reference and Research
on Salmonella at the Pasteur Institute, Paris, France (WHO Collaborating
Centre) is the authority for
maintaining and defining the antigenic formulae of Salmonella serotypes
and Kauffmann-White scheme updates the new serotype annually (Popoff and Le mionr, 1997; Popoff et al., 2000). Kauffmann proposed the one serotype-one
species concept based on the serologic identification of O (somatic) and H (flagellar)
antigens for Salmonella genus
nomenclature (Kauffmann, 1966).Salmonella
is an important Gram negative facultative anaerobic, rod shaped predominantly
motile bacteria with peritrichous flagella, ( except S Gallinarum and S
Pullorum) capable of causing enteric illness in both humans and animals. Salmonella has a diameter of 0. 7 to 1. 5
µm and 2 to 5 µm length. Organism has an optimum growth at a temperature of 370C.
 They catabolise D- glucose and other carbohydrate
and are able to produce acid and gas. Salmonella
is oxidase, indole and Voges-Proskauer negative, catalase, methyl red and
Simmons citrate positive. The organism produce H2S and do not
hydrolyse urea (Holt et al., 1994; Lightfoot, 2004; Percival et al., 2004). In any growth media Salmonella will produce spherical smooth colonies (2-4 mm in
diameter) whereas in Hektoen enteric agar (H. E agar) colonies are like bluish
green with black centers. The disease caused by Salmonella is usually referred to as salmonellosis.
Some of the serovars of Salmonella
are host specific and some are non host specific. Salmonella Pullorum and Gallinarum are two avian specific serovars responsible
for pullorum disease and fowl typhoid in poultry, respectively (de Freitas Neto et al., 2010, Park et al.,
2014).             The most common non specific
serovar present in the poultry are Salmonella
Enteritidis and Typhimurium, they are most frequent cause of foodborne salmonellosis
in human (Foley et
al., 2011;Hendriksen et al., 2011).              In early 1900s there was a peak epidemic of Salmonellosis
due to Salmonella Pullorum and S
Gallinarum in U. S. National Poultry Improvement Plan (NPIP) was established to
combat these disease. Eradication of these avian specific serovar caused the
replacement of their ecological niche by zoonotically important Salmonella serovar (Foley et al., 2011).
           Birds carry the
organism in their gut without any obvious signs of infection, subclinically
infected birds spread the organism easily within the flock (Abulreesh, 2012). Digestive tract of birds, especially at caecum is the
principal site of Salmonella multiplication
(Beal et al., 2006), hence the possibility of environmental contamination
through feces is more (Kabir, 2010)            Chronic Salmonella infection or a recent intestinal colonization or convalescence
after acute infection is characterized by shedding of organism without clinical
sign (Galland et al., 2000). Infection in birds vary from enteritis to systemic
infection depending on the immune status, serovar infected,
overcrowding, age, infectious dose, competition of gut microflora for
intestinal colonization and genetic susceptibility of bird ( Bailey, 1988).              Horizontal
transmission via feed, water, soil, bedding, litter
material, faecal matter, rodents or contact with other poultry and vertical
transmission via egg are the major route of transmission in birds (Tessari et al.,
2012). Salmonella would have
been present in yolk from Salmonella
infected ovary and oviduct (ICMSF, 1980). Otherwise
pathogen may penetrate the egg through egg shell or membrane during cooling
process after laying (Williams et al., 1968). Egg shell contamination without internal
content contamination of egg during the egg laying period is suggestive of
horizontal transmission of disease through the contaminated feces (Pande et al., 2016).
             Usually infection occurs year- round
but the peak infection could be observed in summer and in early fall, but it
may vary with serovar and seasonal contamination. While higher growth rates of
bacteria are observed in warmer temperature (Bryan
and Doyle, 1995). There is a reduction of Salmonella occurrence in birds which are reared under free ranging
condition (Esteban et al., 2008 ).            Lipopolysaccharide associated with
outer membrane, and fimbriae are the two factors responsible for virulence in Salmonella. These structures are
participating in recognition and stimulation of immunity in host (Cogan and Humphrey, 2003).

            Economic loss in poultry industry is
substantiated through poor growth of birds, morality and poisoning of food to
human (EL Fakar and Rabie, 2009). Control of
Salmonella infection is a global
burden, since it causing a negative impact in global economy in terms of treatment,
prevention of illness and cost of surveillance investigation (Pui et al., 2011).Salmonella
an enteropathogen responsible for most of the foodborne infection. Humans
usually get infection by consumption of foods of animal origin such as meat,
milk and egg (Sanchez et al., 2002). CDC is
regularly monitoring of Salmonella
infection associated with poultry and poultry products (CDC, 2010; CDC, 2013).

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           In most of the countries S Enteritidis and S Typhimurium are the most commonly recovered Salmonella serovar in foodborne salmonellosis associated with
consumption of poultry meat and egg (Barrow et al., 2012).

et al. (2016) conducted a 10 years study from 2001 to 2011 and
reported that outbreak of food borne diseases related to S Typhimurium has increased through egg consumption.

           Egg and broilers are the important
sources of Salmonella (Namata et al.,
2009). WHO Salmonella
surveillance data suggested that global increase of salmonellosis is related to
consumption of Salmonella harbored
egg and poultry meat ( Rodrigue et al., 1990).

            Pabilonia et al. (2014) reported the environmental
contamination of Salmonella in a poultry
exhibit. Feed, cages, tables and floors in the exhibit were taken for screening.
They could detect 28 Salmonella isolates
from 55 environmental samples (50. 9 percent) and also identified 11 different
serotypes. These results indicated the possibility of zoonotic transmission of Salmonella to bird exhibits owners and
general public

            An epidemiological study was conducted
to compare prevalence of Salmonella
in a poultry farm, slaughterhouse and chicken meat
in the market. Prevalence of Salmonella
at poultry farm was 4 percent and in
slaughterhouse and chicken meat in the market were 9 percent and 57 percent,
respectively (Padungtod and Kaneene, 2006).

          Rearing and
processing area of duck are a good source of salmonellosis (Adzitey et al.,
2012). Mondal et al. ( 2008) isolated and identified Salmonella organism from diarrhoeic
and apparently healthy ducks and those isolates were highly resistant to

           Salmonella can enter at any point
of food chain. Contamination of poultry carcass can occur at any steps of
slaughtering process like scalding, defeathering, evisceration, cutting,
chilling in water (Northcutt et al., 2003). Dias et al. (2016) tracked and proved
the Salmonella contamination in
different steps of slaughtering and processing of chicken by using conventional
and molecular techniques.

           Salmonella are able to withstand a
wide range temperature for a long period of time, so they remain viable in
frozen foods (Balamurugan, 2010). Failure to
maintain proper temperature in meat storage area can favor the multiplication
of Salmonellae (Bryan and Doyle,1995). Catford et al. (2017) investigated foodborne outbreak by isolating Salmonella from breaded and frozen comminuted raw chicken products. The food sample had
0. 0018 to 3 MPN/g level of organism.With increase in world population, in
order to meet the demand of poultry meat and egg it has been necessary to
increase the production in large scale. Sometime this large scale production
and changes in the husbandry practices may result in, introduction or
prevalence of different serovar of Salmonella

           Salmonellosis is a socioeconomic
problem in many countries, because the disease has been associated with many
public health issues and loss in animal production (Hoelzer et al., 2011). Global and regional estimates of Salmonella disease burden revealed that Salmonella is a one of the foodborne
pathogens causing extra intestinal disease and resulting in deaths and
hospitalization (Kirk et al., 2015).

Salmonellosis is a most problematic zoonotic disease in the world,
because of its high endemicity (Antunes et al., 2003) and the ability to
cause significant morbidity and mortality (Cardoso et al., 2002).

           Sanchez et al. (2002) reported the
evolution of two pandemic serovar S ser Enteritidis and S ser Typhimurium DT104 in U. S,
that have caused high incidence of foodborne salmonellosis in human

         Global monitoring of Salmonella serovar distribution was conducted
during the period of 2001 to 2000, based on the data from 37 countries revealed
that, S Typhimurium was the most
prevalent serovar after S Enteritidis
(Hendriksen et
al., 2011).

        Incidence of food borne
infection by Salmonella in U. S was
estimated as one million (Scallan et al., 2011). This incidence in
U. S population account for roughly 19,336 hospitalizations, 17,000 quality
adjusted life years loss (QALYs) (Batz et al., 2011).

           Heymann, (2008)
reported that in industrialized countries one per cent of the clinically
presented salmonellosis cases were of foodborne origin.

          Zaidi et al. (2006) conducted a three
year Salmonella surveillance study on
human and retail meat samples (chicken, beef, pork), the study reported the
high prevalence of Salmonella, and the
strains found in retail meats were genetically identical to strains isolated
from human sample.

         Immunocompromised individuals especially
HIV patients (Lan et al., 2016), elderly and childrens are more susceptible to
Salmonella infection.

important public health issue related to Salmonella
is acquiring of antibiotic resistance. WHO monitored the rise of antibiotic
resistance in Salmonella due to
indiscriminate use of antibiotic for raising poultry.

resistance pattern of Salmonella
enterica in different species of poultry drawn a serious attention. As a reservoir
of Salmonella they are related to
source of multidrug resistant Salmonella
to human (Mir et
al., 2015).

  From India very high percentage of ESBL
producing non-typhoidal Salmonellae had
been reported from patients admitted to the hospital (Menezes et al.,

 An investigation on the
prevalence of Salmonella in the city
of Southern India supported the world wide increase of S. Enteritidis in chickens (Suresh et al., 2011).    A Study conducted in
North India, investigated the dynamics of Salmonella
occurrence in poultry by identifying the Salmonella
from egg, feed, water, cloaca, and faeces. They could detect 3. 3
percent of Salmonella positive
isolates from the samples and Salmonella
Typhimurium was the predominant serovar present among this isolates ( Singh et al., 2013).

            Kaushik et al. ( 2014) reported the
contamination chicken meat (23. 7 per cent) collected from local markets of
Patna, India with multi drug resistant Salmonella

et al. (2016) isolated 11 different non-typhoidal Salmonella serovars from raw food,
animal and poultry samples of Kolkata. Among these isolates S Typhimurium was the most prevalent

          Condition of salmonellosis in Kerala is
not so different.  Rajagopal and mini, (2013) reported an outbreak of
Salmonellosis and the antibiotic resistance pattern in three different farms of
Kerala. Various other studies are also conducted to identify the public health
importance of Salmonella, especially
on poultry and its product (Anju et al., 2014). Lincy (2016), analyzed Salmonella from meat samples and surrounding environment of the
live poultry market (Surface swab, Hand wash, water) of Wayanad. The study
confirmed the occurrence of Salmonella
from these samples. 

Categories: Industry


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