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  Major reproductive health problems in smallholder dairy production in and around Nazareth town, Central Ethiopia

Y. GIZAW 1, M. BEKANA1 and T. ABAYNEH 1,2

Addresses of authors: 1Faculty of Veterinary Medicine, Addis Ababa University, P.O. Box 34, Debre-zeit, Ethiopia

2Corresponding author (current address): Norwegian School of Veterinary Science, P.O. Box 8146 dep.; N-0033 Oslo, Norway

E-mail: takele_abayneh@yahoo.com

 

Summary

A study was conducted to determine the prevalence of major reproductive problems in smallholder dairy cows in and around Nazareth town from November 2004 to April 2005. Of a total of 403 dairy cows (114 local and 289 cross-breeds) assessed, employing questionnaire survey (n=343) and regular clinical examination (follow-up) (n=60), 31.76 % (n=128) were found to be affected either with one or more of clinical reproductive problems. Endometritis, retained foetal membrane (RFM), repeat breeding and dystocia were found to be the major clinical reproductive problems with prevalence rates of 16.63%, 12.91%, 8.91% and 6.95%, respectively. Abortion (2.23%), anoestrus (1.48%) and prolapses (1.24%) were minor clinical reproductive problems observed in smallholder dairy cows in and around Nazareth. The prevalence of clinical reproductive problems showed significant differences (P<0.05) with respect to breed, parity, production system and body condition (nutritional status) of dairy cows. This particular study indicated clinical reproductive problems, which included endometritis, RFM, repeat breeding and dystocia were one of the major factors responsible for the low reproductive performance of smallholder dairy cows in and around Nazareth town, Central Ethiopia.

Keywords: Dairy cows, Ethiopia/Nazareth, reproductive health problems, Smallholder

Introduction

Cattle production has been considered as the main component of agricultural development in most parts of Sub-Saharan Africa.  The overall cost of keeping cattle in terms of costs associated with the health care, nutrition and management, however, has not matched to their contribution to the livelihood and the economics of the people in the region.

As in many countries, livestock, particularly cattle play multiple roles in Ethiopia being a source of milk, meat, hides, etc (Mekonnen et al., 1989). However, their productivity is low due to various constraints such as disease, nutrition, poor management and poor reproductive performance of indigenous zebu breeds (ILCA, 1988).  Hence income derived from this agricultural sector couldn’t impart a significant role in the economic development of the country (Mukasa-Mugerwa, 1989).

It has been indicated that reproductive problems result in considerable economic losses to the diary industry and are the main causes of poor productive performance of smallholder dairy farms (Roberts, 1986; Bekana et al., 1994a, 1997).  Among the major problems that have a direct impact on reproductive performance of dairy cows, RFM and the subsequent endometritis and pyometra have been reported to be the most common clinical and economical problems (Frederickson et al., 1985; Ijaz et al., 1987; Bekana et al., 1994a, 1994b, 1997). These have been implicated to cause a considerable economic loss to the diary 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 (Borsberry and Dobson, 1989). It has also been shown that low reproductive efficiency hinders genetic improvement in zebu (Bos indicus) cattle and causes direct economic losses (Mukasa-Mugerwa et al., 1991).

In Ethiopia, diary cattle are maintained under different production systems (ILCA, 1994; Shiferaw et al., 2003).  The differences in management (production) systems and environmental conditions under which cattle are maintained could greatly affect the occurrence of reproductive health problems. This particular study is, therefore, carried out to determine the prevalence of reproductive health problems and assess possible risk factors that play a role in precipitating such problems in smallholder dairy farms in and around Nazareth town.

Materials and Methods

Study area

The study was conducted in Adama district located in Oromia Region, central Ethiopia. Nazareth, the capital of Adama district, is located in the Rift valley about 95km Southeast of Addis Ababa at 39.17oN and 8.33oE with an altitude of 1622 meters above sea level. Its average annual temperature ranges from 13.9oC to 27.7oC (Natural Meteorology Service Agency, 1999/2000). Adama district has livestock population of 70,662 bovine; 36,142 ovine; 42,968 caprine; 31, 93 equines; 42 camels and 193,155 poultry (Adama District Agricultural Office, 2003).

Study animals and their management

A total of 403 dairy cows of which 81 were kept under extensive management system while the rest 322 were kept under semi-intensive management system were included in this study during the period November 2004 to April 2005. Classification of management systems was done based on the criteria adopted by Richard (1993). Accordingly, semi-intensive system included all animals that were kept indoor and fed and watered in their house/shade by cut and carry system while extensive management system included all animals that were kept outdoor during the day time and allowed to graze on a communal or private owned pasture land.

Of the 403 cows, 114 were local /zebu breeds whereas the remaining 289 were cross breeds.

Study design

Cross-sectional study, employing questionnaire survey, and regular follow up were employed in this study.

Questionnaire survey: A total of 109 owners and/or attendants were interviewed using structured questionnaire. In the survey, information on reproductive health problems as well as management system and particulars related to individuals cow such as parity, breed and body condition were collected. The various reproductive problems identified were defined and recorded based on the following descriptions/definitions given for each problem.

Abortion: the expulsion of dead fetus or recognizable size before full term of the gestation period (Roberts, 1986; Hafez, 1993).

Anoestrus: a state of complete sexual inactivity with no manifestation of estrus for more than two months (Hafez, 1993)

Dystocia: an abnormal and difficult birth in which the first or specially the second stage of parturition was markedly prolonged and subsequently found impossible for the dam to deliver without artificial aid (Roberts, 1986).

Endometritis: inflammation of the endometrium characterized by reddish brown, white or whitish to yellow mucopurulent foetid vaginal discharge along with thickness of uterine wall detected in transrectal palpation (Morrow, 1986; Roberts, 1986; Bekena et al., 1994a; Bekena et al., 1994b).

Repeat breeding: a cow or a heifer that failed to conceive for three or more consecutive services (Morrow, 1986; Allenstein, 1981; Roberts 1986 and Noakes 1986).

RFM: a lack of expulsion of the fetal membranes with in the first 24 hours after calving (Arthur et al., 1989; Bekena et al., 1994a, 1994b, 1996, 1997).

Uterine prolapse: the coming out of the uterus through the vulva commonly shortly after parturition and hanged out with the inner surface outer most (Morrow, 1986).

Vaginal prolapse: the protrusion of the vagina and some times with the cervix through the vulva (Noakes, 1986; Roberts, 1986).

Follow-up (longitudinal) study

A total of 60 cows that gave birth during the study period were used for the follow-up study. Clinical examination of the reproductive system was regularly carried out to determine the nature of vaginal discharge during the postpartum period. The vulva and perineal area were inspected for the presence of any afterbirth (RFM) if not expelled out with in the first 24 hours (Bekena et al., 1994a) and for the presence of any discharge. Cows with vaginal discharge were subjected to vaginoscopy to determine the type and nature of the vaginal discharge according to Bekena et al. (1994a).

Body condition scoring

Body condition of the study animals was scored based on the criteria set by Richard (1993), which ranged from 0 to 5. Body condition score 0 stands for cows with the poorest body condition while score 5 for cows with the best condition.

Data analysis

Prevalence and the relative frequencies of reproductive health problems were determined as the proportion of affected animals out of the total animals examined and total number of cases, respectively. Chi-square (X2) test or fisher’s exact test was used to assess the effect of risk factors such as breed, parity number, body condition, and management/production system on the prevalence of reproductive health problems (Clark, 1982).

Results

Of a total of 403 dairy cows included in this study, 31.76% (n=128) were affected with one or more reproductive health problems (Table 1).

Table 1. The prevalence rate of clinical reproductive problems of smallholder dairy

cows in and around Nazareth

Method of study

Total number of

Cows Examined

Number of cows with

Problems

Percent affected

Questionnaire survey

343

104

25.81%

Regular follow up

60

24

5.95%

Total

403

128

31.76%

Endometritis, RFM, repeat breeder, and dystocia were found to be the major reproductive health problems accounting 16.63%, 12.91%, 8.91% and 6.95%, respectively. Other reproductive health problems observed with lower frequency included abortion, anoestrus and prolapses (Figure 1 ).

Parity had significant effect (P<0.05) on the prevalence of reproductive health problems with pluripara cows being more susceptible to reproductive problems than primipara cows (Table II).

Significant difference (P<0.05) was found in the prevalence of reproductive health problems with respect to breed and management system with higher prevalence observed in crossbreed (Friesian X Zebu) cows and in those cows managed under semi-intensive management system than indigenous zebu breeds and those under extensive management system, respectively (Table II).

Table 2.  Prevalence of clinical reproductive problems by breed, parity and production

  system

Factors

Number of animals affected

Number of non-affected animals

Animals examined

X2

P-valve

Local/Zebu

25 (36.21)

89 (77.79)

114

7.1

P<0.05

Crossbred

103 (91.79)

186 (197.21)

289

Total

128

275

403

Primipara

21 (29.54)

72 (63.46)

93

4.72

P<0.05

Pluripara

107 (98.46)

203 (211.54)

310

Total

128

275

403

Extensive

18 (25.75)

63 (55.27)

81

4.3

P<0.05

Semi-intensive

110 (102.27)

212 (219.73)

322

Total

128

275

403

Numbers in brackets indicate expected values

Reproductive health problems showed significant variation with regard to body condition scores that ranged from 0 to 5. Highest prevalence was found in cows with body condition score 3 followed by body condition score 2 while the least in cows with body condition score 5 (Table III).


Table 3.  Prevalence of clinical reproductive problems by body condition

Body condition score

Number of affected animals

No of non-affected animals

Number of animals examined

X2

P-value

0

9       (4.41)

5       (9.55)

14

X2=12.16

P<0.05

1

16    (12.92)

25     (27.98)

41

2

37     (35.3)

75     (76.43)

112

3

51     (53.56)

115  (114.64)

166

4

13     (17.33)

42     (37.3)

55

5

2       (4.74)

13     (10.24)

15

Total

128

275

403

Numbers in brackets indicate expected values

Discussion

The prevalence of clinical endometrtis found in recent study (16.63%) fairly agrees with that of 18.7% reported by Oumermohammed (2003) and 19.6% by Gebremariam Tesfaye (1996) in smallholder dairy cows in Kombolcha and Mekele, Northern Ethiopia, respectively. However, the recent result is slightly higher than that of Erb and Martin (1980), Kassahun (2003) and Mamo (2004) who reported an incidence rates ranging from 11.5-13.6%. Higher incidence rate of 67%, 34%, 37%, and 50% have also been reported by Ruder et al., (1990a); Bretzlaff et al., (1982); Markusfeld (1984) and Tackacs et al., (1990), respectively. The variation in the prevalence of endometritis compared to the above-mentioned reports is probably due to differences in the management system in each of the above studies under which the animals were maintained . Furthermore, RFM has been indicated to increase the prevalence of endometritis up to 100% (Allenstein, 1981; Bekena, 1994b).

The prevalence rate of RFM (12.91%) in recent study is inline with those reported in and around Debrezeit (14.28%) (Mamo, 2004) and in central highlands of Ethiopia (7.1-28.9%) (Tekelye et al., 1992). The result obtained in this work also lies within the range of 11.9 to 24.0% reported in other parts of the world (Markusfeld, 1984) but higher than the works of Erb and Martin (1980), Gainse (1989) and Correa et al., (1990) who reported prevalence rates of 7.1%, 10% and 5-8%, respectively. The variation in the incidence of RFM may be attributed to variations in predisposing factors to which the animals are subjected to among which include nutritional status and management. The relatively higher prevalence rate of RFM in the current study could also be due to dystocia that accounted 6.95% of the problems, which is an important predisposing factor for occurrence of RFM.

 The prevalence rate of repeat breeding (8.91%) found in this study fairly agrees with the 5-15% reported by Puntam (1986) but is higher than the 4.6% prevalence rate reported by Tigre (2004) and lower than the 21.8% prevalence rate reported by Mekonnen (2000). Repeat breeder can be caused by a number of factors, including sub-fertile bulls, endocrine imbalance, malnutrition, reproductive tract infections and poor management practices such as wrong time of insemination or faulty heat detection, inappropriate semen handling and insemination techniques (Arthur et al., 1996). In addition to these, communal use of bull for natural services also considered as contributing factor. Hence the difference between the findings of the current study and previous reports may be attributed to the above-mentioned factors.

Previous reports on the prevalence of dystocia by Mamo (2004) (5.79%), Tigre (2004) (7.5%)  and Tadesse (1999) (7.8%) fairly agree to the 6.95% obtained in this study. However, the current finding is lower than the 9.65 % reported by Kassahun (2003), and higher than those of Zewdu (1992) (2.2-4.4%) and Oumermohammed (2003) (4.3%). This variation in the occurrence of dystocia may be due to the fact that it is influenced by factors such as, age and parity as well as breed of the sire (Morrow, 1986 and Noakes, 1986). Inseminating cows with semen collected from large sized bulls without taking into account the size and age of cows is an important factor in precipitating dystocia.

The prevalence rate of abortion (2.23%) recorded in this study is similar to the 3.19% reported by Oumermohammed (2003) but is lower than the 5.33%, 5.4% and 6.3% reported earlier (Shiferaw, 1999; Kassahun, 2003). The lower prevalence rate of abortion may be attributed to the increasing practice of AI in the study area where the semen is collected from bulls free from brucellosis.

The significantly higher prevalence rate of reproductive problems in crossbred animals than indigenous zebu 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 (Tekleye et al., 1991).

The significantly higher occurrence of reproductive health problems observed in puluripara cows in this work is similar to the previous findings (Gebremariam, 1996; Tadesse, 1999; Oumermohammed, 2003; Mamo, 2004) which is possibly due to the repeated exposure of the genital tract of pluripara cows to environmental risk factors that can impart uterine infection.

The current finding of higher prevalence rate of reproductive problems obtained in animals under semi-intensive than those under extensive management practice is in agreement with previous studies ( Tegegne and Gebre wold, 1998 and Kassahun, 2003). This might be related to poor sanitation of the barn, resulting in contamination during calving.

The finding of higher prevalence of reproductive health problems in cows with relatively good body condition (body condition score 3 and 2) compared to those with poor body condition (BCS=0) (Table III) seems to contradict previous explanations that indicated cows in poor condition are the most susceptible to reproductive health problems due to the weak expulsive force to expel out the fetal membranes leading to secondary complications (Roberts, 1986) and the poor body defense mechanism that increases the rate of infection (Isahk et al., 1983). The current finding may be due to the confounding effect of other factors such as parity, breed or management system in that those cows with fairly good condition (body condition 3 and 2) might be pluripara, crossbreed or under intensive management which all predispose to reproductive health problems.

Conclusion

This study revealed that reproductive health problems particularly of endometritis, RFM, dystocia and repeat breeding were one of the major causes of low reproductive performance in smallholder dairy farms in and around Nazareth. Possible risk factors responsible for the occurrence of reproductive health problems identified included crossbreeding, parity and production system. Improvements in management systems (such as housing, feeding and health care), heat detection and proper selection of bulls for breeding taking into account the size of cows could help in minimizing reproductive health problems and hence, improve the reproductive efficiency of smallholder dairy cows in the study area.

Acknowledgements

The authors would like to thank the staff of Nazareth Veterinary Clinic for their technical and material support as well as dairy herd owners for their kind cooperation during data collection.

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First Published January 2007