Association of body weight, scrotal circumference, heart girth and penile development with spermatogenesis in the Nubian bucks

This study was designed to monitor the morphological development of the reproductive tract of the Nubian bucks in relation to puberty. Thirty-two Nubian male kids were used in this study. Their ages ranged between 1 day and 24 weeks. The study was undertaken to correlate the body weight (BW), heart girth circumference (HG), scrotal circumference (SC), testicular descent into the scrotum and penile separation from prepuce (PS) with age at puberty. Penile separation started slightly at 12 weeks of age and continued with advancing age till it was completely achieved between 22 and 24 weeks of age. Strong correlation has been established between the levels of the reproductive hormones and the morphological maturation of the reproductive tract. The first surge in the levels of these hormones (occurred between weeks 10 and 12) coincided with the increase in the diameters of the seminiferous tubules, the epididymis, ductus deferens and the penis. The first appearance of secondary spermatocytes and initiation of penile separation occurred during this period. The second surge was associated with the first appearance of spermatids, spermatozoa and completion of penile separation, which occurred between 20 and 24 weeks. 
 
 Key words:  Nubian bucks, spermatogenesis, body measurements.


INTRODUCTION
Sudan is predominantly an agricultural country with the largest livestock population in the Arab World and ranks second to Ethiopia in Africa.Despite this large population, there is a critical shortage in milk supply and other dairy products.This is mainly due to the poor feeding, poor management and prevalence of diseases.Goats play an important economic role in the livelihood of many Sudanese families.*Corresponding author.E-mail: E-mail: sarashaa@yahoo.com.Tel: +249912433385.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License The local breeds of goats in Sudan embrace the Nubian, Desert, Nilotic dwarf and Taagari.Among these breeds the Nubian goat is recognized as the only specialized milk breed (Hassan and El Derani, 1990).
Goats are used as a representative of large animals for certain experimental purposes like studies on reproduction as the reproductive tracts of the male goat, ram and bull are essentially similar (Goyal, 1985).Among these three species, male goats receive preference because, unlike rams, and bulls, are inexpensive and easier to handle for surgical manoeuvres (Goyal et al., 1999).
The reproductive tract of the male goat consists of testes, epididymis, ductus deferens, penis and the accessory sex glands (seminal vesicles, prostate and bulbo-urethral (Cowper's) gland).The male reproductive tract has been investigated histologically, ultrastructurally and histochemically in several species including bull (Abdel-Raouf, 1960;Mohammed, 2005), camel (Ali et al., 1978;Tingari and Moniem, 1979;Tingari et al., 1984), rat (Pogach et al., 1993) and domestic fowl (Tingari 1972).The goat in general received little or no attention.In spite of the importance of the Nubian goat, there is no reference in the literature dealing with the characteristics pertaining to the morphological and physiological changes of the reproductive tract prior to the age of puberty.
Puberty is reached when sexual organs have become fully developed (Abdel-Raouf, 1960), the sexual instincts are prominent and reproduction is possible.The objective of this study is to examine the changes in the morphological parameters in the male reproductive tract of the Nubian bucks prior to the age of puberty.

MATERIALS AND METHODS
This research work was conducted in the period between May, 2001 andMay 2002.Samples were obtained from different parts of the male reproductive tract including the testis, epididymis, ductus deferens and penis of 32 Nubian male kids, from birth up to six months of age.Samples were taken at 15 days interval for investigation.The different groups were represented by at least two animals each.The animals were used initially for data collection including; body weight (BW), scrotal circumference (SC), Heart Girth (HG), testicular descent into the scrotum and penile separation from prepuce.

Statistical analysis
A computer package for statistical analysis was used (SPSS version,11).The data obtained were computed to find correlations between body weight (BW), scrotal circumference (SC), Heart Girth (HG) in association with penile separation and appearance of spermatozoa in the seminiference tubules.

Body weight (BW)
The result showed that body weight in Nubian male kids increased with age in a linear pattern starting with 2.3 kg at week one and ending with 13.5 kg at 24 weeks of age (Figure 1).

Heart girth circumference (HG)
Heart girth measurements increased with age in a linear pattern, reaching higher values at 22 weeks of age.HG showed a strong correlation (P< 0.1) with age (Figure 2).

Scrotal circumference (SC)
SC measurement increased with age in a linear pattern reaching the maximum at 22 weeks of age (Figure 3).There were strong correlations between SC and BW (P< 0.01) and between SC and HG (P< 0.01).

Correlation between the body weight (BW), heart girth circumference (HG), scrotal circumference (SC)
Very strong positive correlations were found between the BW, heart girth circumference (HG) and scrotal circumference (SC) (Tables 1 and 2).

Penile separation from the prepuce
The diameter of the penis was 6988 µm wide at week one.The skin was closely adherent to the underlying tissue in which Meissner's corpuscles were seen.An inner folded band encircled the corpus spongiosum penis and corpus cavernosum penis and consisted of about ten layers, mainly cuboidal cells in the center, covered on either side by columnar cells and overlying layer of connective tissue containing band of smooth muscle fibers and collagen fibers.Penile separation started slightly at 12 weeks of age and continued with age till it  was completely achieved between 22 and 24 weeks of age (Figures 4 and 5).

Puberty
Based on the first appearance of spermatozoa in the seminiferous tubules, puberty was reached in Nubain male kids at the age of 22 weeks.At this age penile separation was completed (Figure 4), body weight was11.5 kg, heart girth was 52.5 cm and scrotal circumference was 13.5 cm.

DISCUSSION
This study was conducted in different seasons and the results were not affected by seasonal changes, since the Nubian goat is a tropical breed and has no pattern of seasonal breeding, (Kurohmaru and Nishida, 1987;Ritar,      1991).With regard to data on measurements of scrotal circumference, heart-girth and body weight, good correlations were found between these parameters and age.These body measurements reached their maximum at the age of puberty (22 -24 weeks).Similar findings were also reported in man (Forest et al., 1976), monkeys (Mann et al., 1994;Lunn et al., 1997), ram (Dun, 1955), and sheep (Louw and Joubert, 1964).
The environment for the bucks used in this study was the same in relation to feeding, management and housing.Thus nutrition was not considered as a variable.However, some researchers focused on nutrition to be the most important factor that can affect body measurements in small domestic animals (Setchel et al., 1965;Martin et al., 1994;Thwaites, 1995a).
For the determination of age of puberty, evidence for commencement of spermatogenesis was considered in this study.Thus, puberty in Nubian bucks was reached at 22 weeks of age (Shaaeldin, 2006).Moreover, penile separation was also completed at the same age.Similar findings have been reported on measurement of scrotal circumference, heart girth, and body weight in other breeds of goat and sheep which were indicative of puberty to be at the age between 18 and 22 Weeks.The maximal levels of plasma protein (PRL), testosterone, LH, FSH was reached between 18-20 weeks (Shaaeldin, 2015), which give further support to pubertal characteristic of goat.
However, other breeds of goat and sheep reach puberty between 16 and 21 Weeks (Louw and Joubert, 1964) and 30 weeks (Nasir et al., 2013).Dyrmundsson (1973) noticed that there were great differences in age of puberty and body weight between ram lambs of various breeds of sheep.Large animals are said to reach puberty at the age between 23-26 weeks (Abdel Rahim, 1997).The present study confirms earlier observations that signs of puberty in the Nubian bucks appeared around 22-24 weeks of age.Maturity would be achieved a few weeks later reaching up to one year of age (Renaville et al., 1993;Adil and Nasir, 2015).

Conclusion
The results obtained revealed the age at puberty for the first time in male kids of Nubian goat depending on the first appearance of spermatozoa in the seminiference tubules.The associated body measurements could be used as simple guide for selection of breeding males at puberty.Nevertheless, age at sexual maturity still needs more time to accomplished, it will be a subject for future research.

INTRODUCTION
Ethiopia is believed to have the largest livestock population in Africa.This livestock sector has been contributing considerable portion to the economy of the country and is still promising to contribute to economic development of the country.The Ethiopian total cattle population is estimated to be about 56.71 million.Out of this, the female cattle constitute about 55.45 and 98.66% of the total cattle in the country are local breeds and the remaining are crossbreed and exotic breeds that accounted for about 1.19 and 0.14%, respectively CSA, 2015).The livestock sector plays a vital role as source of food, income, services and foreign exchange to the Ethiopian economy (Ayele et al., 2003).For several years, Ethiopia ranked first in cattle population in Africa.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License (However, the dairy industry is not as developed as that of east African countries; the national milk production remains the lowest in the world even by African standard (Kassa and Lema, 2005).Milk production in the country is mainly from indigenous cattle breeds, which are kept for multi purposes in the different agro ecology and production systems.The first attempt for the improvement of dairy cattle production in Ethiopia was founded in the late 1960s through the introduction of exotic dairy breeds and use of reproductive technologies (Ahmed et al., 2003).Cow regular breeding depends upon the normal function of the reproductive system.In order to breed regularly, the cow has to have functional ovaries, display estrous behavior, mate, conceive, sustain the embryo through gestation and resume estrus cyclicity and restore uterine function after calving.Each of these aspects of reproductive function can be affected by management, disease and the genetic make-up of the animal.When the function of the reproductive system is impaired, cows fail to produce a calf regularly (Shiferaw et al., 2005).
Reproductive problems have been implicated to cause considerable economic loss to the dairy industry due to slower uterine involution, reduced reproductive rate, prolonged inter-conception period and calving interval, high cost of medication, drop in milk production, reduced calf-crop and early depreciation of potentially useful cows (Bekana et al., 1997).In addition, several studies indicate that reproductive disorders are the most frequent culling reasons (Stevenson et al., 1998).The major problems that have direct impacts on reproductive performance of dairy cow were abortion, dystocia, retained fetal membrane, metritis, prolapse, anestrus and repeat breeding (Lobago et al., 2006).For the production constraints, reproductive health problem (RHP) plays major part but, in the present area there is no study reported thus.The present study was conducted with objective to assess the reproductive health problems and associated risk factors with the reproductive health problem in the area.

Study area
The study was conducted from November 2016 to March 2017 in and around Boloso Sore District, Southern Ethiopia.Boloso Sore is located in the Wolaita Zone of the Southern Nations, Nationalities, and Peoples' Region, 300 km southwest of the capital city of Ethiopia, Addis Ababa.The area has a latitude and longitude of 7°05′N 37°40′E / 7.083°N 37.667°E and an altitude of 1350-2380 m above sea level.

Study population
Based on the accessibility and dairy potentials in line with zonal dairy estrous synchronization program, four kebeles were purposively selected and using semi structured questionnaire randomly sampled smallholders were interviewed.The owners were interviewed by local language and data were collected on reproductive health problems, dairy reproductive performance and demographic situation of the smallholder in the area.

Study design and sampling procedures
A cross sectional study was conducted from November 2016 to March 2017 in and around Boloso Sore district.From the study, district through multistage sampling technique, four kebeles namely Dola, Xadisa, Hangada and Puxo were purposively selected based on their accessibility, and existing dairy potential in line with zonal dairy estrus synchronization program.Household's data list who own dairy cattle were captured from the kebeles administrative office, and individual owners for interview were taken by simple random sampling method using lottery system.

Sample size determination
In four kebeles, of the total households, 5080 dairy owners with herd size more than one dairy cows were considered and based on the formula, questionnaire survey sample size was calculated by using the formula given by Arsham (2002) which is: N= 0.25/SE 2 , Where N= sample size, SE (standard error=5%).The sample size required for the questionnaire survey as per the above formula is 100 for the site.However, to include different risk factors in consideration of kebeles area coverage and large household size, and to increase the precision of the result, the number was increased double across the four kebeles and so a total of 200 individuals were interviewed.

Data analysis
The data were entered and managed in Microsoft Excel.SPSS version 20 software was used for the data analysis.The differences in parameters such as, breed, calving interval, parity and other factors on reproductive problems were analyzed by using χ2 (Chisquare) test, and the level of significance was set at 95% confidence interval.

RESULTS
In this study, a total of 200 smallholder dairy owners 68.5% male and 31.5% female were interviewed from the selected four kebeles based on smallholder number proportion; 49, 53, 44 and 54 respondents householders were used from Hangad, Puxo, Xadisa and Dola respectively in this data analysis (Table 1).Fifty two percent of the farm owners responded that their cows were affected by either one or more reproductive health problems.The major reproductive disorders in the district were repeat breeding, dystocia, retained fetal membranes, abortions, uterine prolepses and still birth.
Respondent's belongs to adult age group which indicates the consistency of the data generated for average age of 31.12±5across the kebeles.Concerning the level of education, the highest percentage (54.5%) of the respondents were illiterate, followed by 37.5% which studied in elementary school, and 4.5% of the respondents had attended high school and 3.5% had college diploma education across the kebeles.Average family size in the area was about 4.81±1.75.With regards to the individual, and spouse occupation, 33.5% were actively involved in livestock rearing and the rest (66.5%) were involved in agricultural activities other than livestock keeping due to feed challenge and low initial investment capacity.
Average cattle herd size at individual household level was found; about 3.39±1.8head of cattle were recorded and the largest portion was local breed accounting for 80% followed by 20%; cross Holstein Friesian (HF) distribution was statistically significant across the kebeles.In this study, average lactation length, calving interval, and average age for heifers at first bull service was 9.2±2.7,15.21±5.72 and 38.1±6.6 in month's respectively and were statistically significant across the kebeles.An average lactation length of 9.2±2.7 shows that, cows had the second pregnancy which was statistically significant across the kebeles.Actually, there should be about 45-60 open days gap between the calving to the next heat sign unless it will lead to the postpartum complication; this significant record difference indicated the presence of prevalent postpartum complication in the area reported in this study.In the present study, two potential sources for breeding animals origins were identified and overall, 71% of the animals originated through birth and 29% were through market purchase process and the respondent consent across kebeles were not statistically significant, which indicted that reproductive health problems were enzootic and could be mainly management related.For the breeding practice, 62% respondent use conventional bull service followed by 30.5% which use artificial insemination and 7.5% use other alternative and the respondent consent were found to be statistically significant.This could have emanated from inconsistence AI service delivery system, poor heat detection and letting dairy cows free grating in the pasture through mixed herding.For the respondent consent overall, 87.5% respondent had no regular vaccination for the herd for any communicable livestock disease in the area and responded that no vaccination calendar was set by the service delivery system.
In the present study, the history of reproductive health problem at household herd level were 52% (n=104/200) and the respondent consent were statistically significant across the kebeles.Based on the respondent consent, animal with increased parity stage (2.6±1.6)showed history reproductive disorder and to the type of reproductive health problem identified repeated, breeder syndrome, dystocia, abortion, retained fetal membrane, uterine prolapsed, mixed type and still birth were 17, 16.5, 14.5, 5.5, 3.5, 1.5 and 1% respectively based on their importance.52% of the respondent knew no identified root cause on the occurrence of the reproductive health problem in the herd and the consent recorded statistically significant in the kebeles.Based on the consent, the herd level history abortion occurs during second half of gestation (5.78±1.72)and the responses were statistically significant for kebeles.From Tables 2 and 3, herd size, parity stages, dairy breed and breeding service type were used to assess the association with the occurrence of the reproductive problems.In the present study, with the increase of herd size, the respondent consent indicate there was association of history of reproductive health problem occurrence in the herd by 66.7, 42.3 and 36% for larger, small and medium herd size respectively which was not significant statistically.Respondent consent for the association of breed to the history of reproductive health problem occurrence were found higher in cross breed than local by 59.1 and 34.5% respectively and were statistically significant (Table 4).Similarly, with the increase in number of parity have a significant influence the occurrence of reproductive problems that, the effect increased progressively from primiparous to multiparious (37% and 75.4% respectively) since postpartum complication and owner attitude towards dairy management are inversely related that, the production system was purely traditional and with the increase in exotic blood level condition like postpartum complication were increase.

DISCUSSION
Based on the overall respondents consent, 52% (n=104/200) herd level history of reproductive health problems were recorded which was higher when compared with 39.5% found by Wagari and Shiferaw (2016), and 24.8% by Bitew and Prasad (2011), Wujira and Nibret (2016), Madot and Nibret (2015) and Abebaw et al. (2009) who reported 35.5, 29 and 33.59% in and around Horro Guduru Wollega, Bedelle zone, Wolaita sodo, Jimma and Gondar town respectively.The differences were due to difference in dairy management and agro ecological.In the present study, repeat breeder  syndromes, dystocia, abortion, RFM and uterine prolapse were found to be the major reproductive health problem identified in the area.The higher occurrence for repeated breeding syndrome (RBS) by 17% were factored by use of sub fertile bulls, management practices like insemination timing, faulty heat detection and inconsistence breeding services delivery system which agree with the repot in the country by Ararsa and Wubishet (2014); Adane et al. (2014); 10.3 and 13.08% respectively in and around Borena Oromia and Hossana town are also contributing factors and the portion of dystocia, may be due to parity of the dam as well as the breed of the sire (Arthur et al., 2001).Also, the present record for RBS was higher than the study report in the country, 3.87% by Dawit and Ahmed (2013); 2.9% by Bitew and Prasad (2011) and 1.3% by Abebaw et al. (2009); this high report was due to the synchronization program intervention by individual cow's physiological response difference to prostaglandin injection.In this study, an abortion history most commonly occurs during their second half of gestation which is 5.78±1.72 in month and was statistically significant across kebeles.The occurrence of abortion in this study was about 14.5%, which strongly agrees with the findings of Kifle and Moges (2016) who reported 19.7% in and around Gondar town and Adane et al. (2014) who reported 13.08% in and around Hosanna town.This study shows that abortion in dairy cattle was found to be more common in pluriparous cows at advanced pregnancy stage.The possible predisposing condition of abortion was identified as both mechanical and infectious cause but, need further investigations to identify the etiology.The record for retained fetal membrane (RFM) (5.5%) agrees with the report of Ayana and Gudeta (2015) in selected sites of central zone of Tigrai region, northern Ethiopia reporting an occurrence of 8.3 and 7.18% in Hossan town RHP=reproductive health problem; χ2 = chi square; significant P<0.05**; NS, non-significant; P >0.05.(Adane et al., 2014).The much incidence of RFM might be linked to the low incidence of abortion a known predisposing factor for RFM.Other factors such as year of calving, season of calving, parity of dam, calving difficulty and fetal presentation have all been shown to affect the incidence of RFM (Arthur et al., 2001).The higher occurrences of reproductive problems in crossbred cattle (59.1%) than local breed (34.5%) may be due to the fact that European breeds are less adapted to tropical conditions of high temperature and humidity, disease and low feed quality than zebu cattle Mukasa-Mugerwa (1989) making them more susceptible than indigenous zebu.Another reason may also be due to the fact that, cross breeds require more elaborated management, feeding and better health care than the indigenous zebu to get better reproductive performance and productivity in the tropics (Tekelye et al., 1991).Significantly higher occurrence of reproductive health problems observed in multiparous cows (75.4%) in this work is in agreement with those of previous findings by Micheal (2003) which is possibly due to the repeated exposure of the genital tract of pluriparus cows to environmental risk factors that can impart uterine infection.It can also be due to older cattle are not as such good in feed intake capacity and decrement in natural immunity as age increases.Even though the service type (AI or natural mating) of the study animals did not influence the occurrence of reproductive health problems in the present study, that is statistically nonsignificant, It was high in those which use artificial insemination (50%) than (34.5%).

Conclusions
The present study revealed a high occurrence of reproductive health problems, of which repeat breeder, dystocia, abortion and retained fetal membrane were found the most common problems of dairy cows identified in the area.Also, this study indicates that the association of history of reproductive problems showed significant difference with respect to breed and parity of dairy cattle thus; Holstein cross breed dairy with increased parity was recorded to have history of reproductive health problem than others in the management system.Further studies should be conducted at different cross breed level, and awareness should be creation to farm owners and attendants to improve dairy management with increased parity.Many small holders' farms are run as a sideline business and are often victimized with improper management thus; putative risk factors responsible for the occurrence of reproductive health problems were breed, service type and parity stage.Therefore, improving management like herd health care, heat detection and proper selection of bulls for breeding will minimize the problems and hence increase reproductive efficiency of dairy cows in the area.

INTRODUCTION
Poultry is a rapid growing sector throughout the world.It has been found that market share poultry meat is about 2 to 2.5 in 1971 that has been increase to 25% in 2010 (GOP, 2013).It is economical to stockholders due to large farming size, quick output, genetic improvement and improvement in feed stuff (Martinez, 2002;Morrison et al., 2004).Despite worldwide growth of poultry, it is influenced by various infectious pathogens including infectious bronchitis virus (IBV) (Sandhu et al., 2009).
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution License 4.0 International License  (Sediek, 2005).Drop in egg production, poor quality eggs, misshapen, broken and weak shelled eggs (Seidek, 2010) followed by reduction in egg production up to 50% (Biswas, 2004) and loss shell colour (Cook and Huggins, 1986).The infection is responsible for causing morphological and histopathological changes in oviduct which influence laying of eggs (Jane et al., 2012).Prevalence of infectious bronchitis virus has been increased that lead heavy morbidity and mortality.The prevalence of infectious virus in commercial poultry is about 82.43% (Hadipour et al., 2011).Outbreaks of IBV have been increased in last few decades in countries such as Tunisia, Egypt and Asia that caused heavy economical losses (Yu et al., 2001).Keeping in view the high morbidity and mortality due to recent outbreaks of Taiwan Group I CK/CH/LDL/97I strains of IBV (Chen et al., 2010;Jinling et al., 2012), this study is designed to investigate the prevalence and clinical pathologies caused by infectious bronchitis virus (IBV) in Pakistan.

Sample collection and transportation
A total of 4000 tissue specimens (trachea, kidney and tracheal swabs) were collected from flocks with respiratory illness from various districts of Sindh (Karachi, Thatta, Mirpur khas, Larkana and Sukkur), from November 2015 to January 2016.In order to investigate prevalence and quantification of IBV samples were taken from 200 farms (broiler and layers with 1:1 shown in Table 1).Samples were transferred in test tubes containing sterilized phosphate-buffered saline (PBS) supplemented with penicillin (10,000 IU per ml), streptomycin (10,000 ug ml -1 ) and nystatin sulphate (1000 IU ml -1 ) as described by Mahmood et al. (2004).The samples were shifted to research and development laboratory and preserved at -80°C.

Virus isolation
One gram of sample was homogenised in 700 ul of PBS, after adding 35 ul of antibiotics.The supernatant was injected to 10 dayold embryonated chicken eggs, amnio-allantoic fluid was harvested 72 h post inoculation and it was subjected to rapid HA test as described by Doherty (1967).A volume of 125 ul of samples with negative rapid HA was treated with 25 ul of trypsin then micro HA was performed (Mahmood et al., 2004).

ELISA
An antigen ELISA kit was used to detect IBV that contained antibody coated microtiter plate wells.A volume of 40 ul of tissue homogenate missed with 10 ul of sample diluent, poured in wells and incubated for 30 min.After the addition of horseradish peroxidase (HRP) conjugate antigen and antibody complex was generated.Chromogen dye followed by stop solution was added the blue color changed to yellow color after incubation in dark room, optical density (OD) value was calculated at wavelength of 450 nm by using automatic ELISA reader after that (S/P) ratio (absorbency of sample / absorbency of positive control) was determined as described by Wang et al. (2002) and Chen et al. (2003).The samples with S/P ratio ≥ 0.2 were considered positive for IBV.

RESULTS
Results explored that Infectious bronchitis virus (IBV) is characterised by general respiratory signs such as severe conjunctivitis, lacrimation, gasping, sneezing, watery eyes, tracheal rales and coughing.Postmortemlesions include damaged epithelium of trachea, tracheal haemorrhages, sero-mucus exudate in trachea and congested lungs with prominent infiltration of seromucus exudates (Figure 1a to d).
Additionally, it has been investigated that kidneys were severely congested, inflamed, pale and distended with prominent urates leading peri hepatitis and aracialities.Moreover, proximal tubules and convoluted tubules were inflamed (Figure 2).
Results have found that IBV reduced egg production; poor quality eggs, weak shelled eggs, misshaped eggs and cracked egg (Figure 4a to d).Similarly, it damaged the ovary as a result egg yolk is evenly found in abdominal cavity (Figure 4b).

DISCUSSION
Despite expeditious growth of poultry in Pakistan, this is the first study on overall prevalence of IBV throughout Sindh.The current study had determined that IBV is a major respiratory pathogen that causes catastrophic morbidity; mortality leads to heavy economic loss.The study investigated that IBV infected birds characterized by signs, that is, severe conjunctivitis, lacrimation, gasping, sneezing, watery eyes, severe tracheal rales and cough (Figure 1a to d).Correspondingly, severe conjunctivitis, lacrimation, sneezing, mild tracheal rales and cough have been reported in 2013 in Egypt (Sediek and Awad, 2014).Additionally, IBV infected birds were depressed, lethargic, reluctant to move and take feed these finding was in agreement with (Terregino et al., 2008) Main lesions in respiratory tract were reddish streaks ranging from mild to severe, increased concentration of mucin in trachea with accumulation sero-mucusexudates in trachea and bronchi (Figure 1c).These findings are correlated with Terregino et al. (2008) and Sediek (2010).However, lungs were congested, discoloured, infiltrated with mucus leading to pneumonia (Figure 1b) that were similar with previous reports (Sediek, 2010).It has been found that sero-mucus exudates in trachea is due to degeneration of cilia by viropexin enzyme produced by IBV (Ashraf et al., 2010).Similarly, infiltration of inflammatory cells in the lamina propria and submucosa, activation of goblet cells, oedema in the submucosa, epithelial lymphoid infiltration, epithelial hyperplasia in trachea have been reported (Cavanagh and Naqi, 2003;Terregino et al., 2008;Sediek, 2010).IBV severely damaged urogenital system especially renal abnormalities (nephritis, pale and enlarged kidneys).Moreover, kidney was bulged from renal cavity, inflamed and distended with prominent urates (Figure 2a and b).Correspondingly, Sediek (2005), Sediek and Awad , (2014) and Abdel-Moneim et al. (2002) found that IBV caused severe congestion, pale and congested kidney with prominent urates, peri hepatitis and airsaculitis.On the contrary, nephritis is seen in naturally infected flocks were due to Nephritis Nephrosis Syndrome (NNS) (El-Sisi and Eid-Amal., 2004).The results of the study differ from that of Ashraf et al. (2010) as they reported that IBV isolate 22 does not produce renal lesions in artificial infection.
Results have found that the severity and prevalence percentage of IBV varies with age and type of birds like IBV produce more severe infection in broiler than layer flocks but prevalence percentage is more in layer than broiler that could be due to repeated exposure of layer to same pathogen.Additionally, IBV adversely affect performance of layers and quality of eggs (misshapen, weak shelled, cracked shell, missing of shell with accumulation of yolk in abdomen) (Figure 4a to d).These results are in agreement with previous studies that IBV infected birds have poor laying percentage along with bad quality eggs (Sediek and Awad, 2014).Interestingly, IBV during growing period appears to have minor effect on the ability of hen to produce eggs of normal quality (Jane et al., 2012).

Conclusion
Infectious bronchitis virus is an acute and highly contagious disease of poultry.It causes respiratory distress, heavy morbidity and mortality.Prevalence of IBV is slightly higher in layers (61.2%) than broilers (52 %).Therefore, studies must be conducted on the prevalence, isolation and mechanism of infection and preparation of vaccine from local isolates in-order to prevent economic losses.

Figure 1 .
Figure 1.Body weight changes (Kg) with age (weeks) in Nubian male kids.

Figure 3 .
Fig. 1 Body Weight Changes (Kg) with Age (weeks) in Nubian Male Kids

Figure 4 .
Figure 4. Division into two layers of stratified squamous epithelium has started (arrow) 40000X.

Figure 5 .
Figure 5. Complete separation of epithelium band has been completed (arrow) 640X.

Figure 3 .
Figure 3. Prevalence % of IBV in broiler birds (a) and layer birds (b) at various districts of Sindh.

Figure 4 .
Figure 4. (a) Poor quality egg with ruptured shell; (b) Egg yolk distributed in abdominal cavity shown with single arrow head and suppressed shell shown with double arrow.(c) Weak eggs shell with dimples shown by arrow heads.(D) Cracked egg shell.

Figure 5 .
Figure 5. Detection of IBV through ELISA.Samples with S/P value ≥ 0.2 were considered as positive while samples with S/P value ≤ 0.2 were considered as negative
The rainfall pattern is bimodal; a short rainy season runs from March to May and long rainy season runs from June to September with average annual rainfall of 1300 mm and average daily temperature of 20.4°CThe district is bordered by Boloso Bombe in the West, Hadaro Tunto of kembata Tembaro North West, Sodo zuria and Damot Sore South and Damota Gale in the East.An administrative center of the district, Areka was establish 1959, and Ethiopian Institute of Agricultural Research

Table 1 .
Socio-demographic data of characteristics of households in the study district (Mean± SD, frequency and Chi-square values).

Table 2 .
Dairy reproductive and productive performance (Mean± SD, frequency and Chi-square values).

Table 3 .
Reproductive health problems in the study area (Mean± SD, frequency and Chi-square values).

Table 4 .
Association between history of RHP and putative risk factors (Frequency and Chi-square values).

Table 1 .
Sample collection for IBV isolation.