Factors affecting the reproductive performance of Awassi sheep flocks in north-east of Jordan: An epidemiological study

A prospective cohort study was conducted using 32 randomly selected Awassi sheep flocks to identify factors hypothesized to be associated with the occurrence of pregnancy, twinning and fetal loss between August 2005 and May 2006 in the region of Al-Safawi (northeast of Jordan). Vitamins A and E and selenium concentrations were determined on 448 blood samples. Using the forward selection procedure of the logistic regression module, models with statistically significant risk factors (P?<?0.05) were constructed for three outcomes; pregnancy, twinning and fetal loss. Serum vitamin A concentration levels were associated with pregnancy (OR?=?2.26, 2.48), twinning (OR?=?6.49, 17.74) and fetal loss (OR?=?0.13, 0.19). Primiparous ewes were 48% less likely to become pregnant than fourth or higher parity ewes. The likelihood of twinning increased significantly in ewes up to the third parity. Ewes that were fed 700-900 g barley, 250-300 g wheat-bran per head per day and grazed on vegetables residues were 4.15 times more likely to have twins than ewes that were fed 600 g barley and 200 g wheat-bran per head per day. Fetal loss in first and second parity ewes was about 3 times more likely than that in third or higher-parity ewes. Ewes pregnant with twins were about 14 times more likely to have fetal loss than ewes carrying single fetus. Pregnant ewes of the stationary flocks were 37% less likely to have fetal loss than ewes of the semi-nomadic flocks. These results demonstrate that stationary Awassi sheep flocks had higher pregnancy and twinning rates and less pregnancy loss. Supplementation of vitamin A, providing sufficient quantity of dry feed and increasing ram: ewe ratio for primiparous ewes of semi-nomadic flocks is essential to improve Awassi sheep reproductive performance.     

Seroprevalence and risk factors for bovine brucellosis in Jordan

We investigated the seroprevalence and risk factors for Brucella seropositivity in cattle in Jordan. The sera from 671 cows were randomly collected from 62 herds. The antibodies against Brucella were detected using a Rose Bengal plate test and indirect ELISA. A structured questionnaire was used to collect information on the cattle herds'' health and management. A multiple logistic regression model was constructed to identify the risk factors for Brucella seropositivity. The true prevalence of antibodies against Brucella in individual cows and cattle herds was 6.5% and 23%, respectively. The seroprevalence of brucellosis in cows older than 4 years of age was significantly higher than that in the younger cows. The seroprevalence of brucellosis in cows located in the Mafraq, Zarqa and Ma''an governorates was significantly higher than that of the other studied governorates. The multiple logistic regression model revealed that a larger herd size (odd ratio = 1.3; 95% CI: 1.1, 2.6) and mixed farming (OR = 2.0; 95% CI: 1.7, 3.7) were risk factors for cattle seropositivity to Brucella antigens. On the other hand, the use of disinfectants (OR = 1.9; 95% CI: 1.1, 2.1) and the presence of adequate veterinary services (OR = 1.6; 95% CI: 1.2, 3.2) were identified as protective factors.     

Blood and milk status of vitamin E,vitamin A,and selenium in nursing Awassi ewes injected with vitamin E and selenium

Abstract

This study investigated the effects of vitamin E and selenium (Se) injections on concentrations of vitamin E, vitamin A, and Se in blood and milk to predict when injections may improve ewes’ performance. Awassi ewes received 0 (control, 13 ewes) or 15 plus 0.05?mg/kg BW of vitamin E and Se (injected, 15 ewes) at 1 and 4 weeks postpartum. Blood and milk samples were collected weekly for 6 weeks. Injections increased vitamin E, decreased Se, and had no effects on vitamin A levels in blood. Blood vitamin E was correlated positively with vitamin A. Injections increased vitamin E, but had no effects on vitamin A or Se levels in milk. Milk vitamin A was positively correlated with vitamin E and Se levels in the control group. Milk vitamins E and A were positively correlated with their corresponding levels in blood. Milk somatic cell count was negatively correlated with blood vitamin A levels.     

Prevalence and risk factors associated with Chlamydophila abortus infection in dairy herds in Jordan

A cross-sectional study was carried out to determine seroprevalence and to identify risk factors associated with Chlamydophila abortus infection in 62 nonvaccinated dairy herds (671 cows) in Jordan between January and June 2007. Information regarding herd management was recorded through a personal interview with farmers. Antibodies against C. abortus were detected using an ELISA test kit. Chi-square analysis and multivariable logistic regression model were used to identify risk factors associated with C. abortus seropositivity. The true prevalence of antibodies against C. abortus in individual cows and cattle herds were 19.9?% and 66.3?%, respectively. Univariable Chi-square analysis revealed three variables with P????0.25 that were further offered to multivariable logistic regression analysis. Small-sized herds were identified as a risk factor for seropositivity to C. abortus, while sweeping followed by water hosing and using disinfectants were identified as protective factors. Cows in the age groups of >8 and ??10?years old and >2 and ??6?years old had the highest and lowest significant seroprevalence to C. abortus, respectively. Results of this study indicated that C. abortus is highly prevalent in Jordan's dairy herds and Chlamydophila infection could be controlled by applying strict biosecurity measures in the dairy farms.     

Awassi sheep reproduction and milk production: review

Awassi is the local breed of sheep in Jordan and is the most important breed in the semi-arid regions of the near east countries. Awassi ram and ewe lambs reach puberty at around 8 and 9 months of age, respectively. The breeding season of Awassi ewes starts as early as April and lasts through September. After puberty, Awassi rams are sexually active throughout the year. The normal estrous cycle in Awassi ewes is 15–20 days (average 17 days). Estrus ranges from 16–59 h (average 29 h) during the breeding season. The reproductive performance of unimproved Awassi sheep has been low while improved Awassi has the highest fertility and milk production and are the heaviest among all Awassi populations. The gestation length varies from 149 to 155 days (average 152 days). Hormones that are commonly used for induction and synchronization of estrus in Awassi ewes include progestins, gonadotropins and PGF2α. An Awassi ewe produces 40–60 and 70–80 kg of milk per 150-day lactation period under traditional and improved production systems, respectively, in addition to the suckled milk left for lambs until weaning. The improved Awassi has the highest milk production among all Awassi populations and may reach 506 L over 214-day lactation period. The objective of this review is to summarize the reproductive pattern and milk production of Awassi sheep in the Middle East region.     

Prevalence and risk factors associated with Neospora caninum infection in dairy herds in Jordan

A cross-sectional study was carried out to determine the seroprevalence and to identify risk factors associated with Neospora caninum infection in 62 dairy herds (n?=?671 cows) in Jordan between January and June 2007. Information regarding herd management was recorded through personal interviews with farmers. Antibodies against N. caninum were detected using an indirect ELISA test. Chi-square analysis and multivariable logistic regression model were used to identify risk factors associated with N. caninum seropositivity. The true prevalence of antibodies against N. caninum in individual cows and cattle herds was 35 and 66.5 %, respectively. There was no significant difference in the percentage of seropositive animals between different age groups. Multivariable logistic regression model revealed workers frequently visiting nearby farms as a risk factor for seropositivity to N. caninum, while presence of a calving pen was suggested as a protective factor. Amman, Balqa, and Mafrak governorates had significantly lower seroprevalence to N. caninum compared to other Jordanian governorates. Results of this study indicated that N. caninum infection may be widespread in Jordan.     

Prevalence and risk factors associated with bovine viral diarrhea virus infection in dairy herds in Jordan

A cross-sectional study was carried out to determine the seroprevalence and to identify risk factors associated with bovine viral diarrhea virus (BVDV) infection in 62 non-vaccinated dairy herds (671 cows) in Jordan between January and June 2007. Information regarding herd management was recorded through a personal interview with farmers. Antibodies against BVDV were detected using an indirect ELISA test. Chi-square analysis and multivariable logistic regression model were used to identify risk factors for BVDV seropositivity. The true prevalence of antibodies against BVDV in individual cows and cattle herds was 31.6% and 80.7%, respectively. The seroprevalence of BVDV in medium and large size herds was significantly higher than that in smaller herds. There was no significant difference in BVD seroprevalence between different age groups. Random-effects logistic regression model revealed two major factors associated with seropositivity to BVDV; exchange of visits between adjacent farm workers and not isolating newly purchased animals before addition to the herd. The seroprevalence of BVDV in cows located in the northern Jordanian governorates was significantly higher than that in other studied governorates. Results of this study indicated that BVDV is highly prevalent in Jordan and BVDV infection could be controlled by livestock-trade control, and applying strict biosecurity measures in the dairy farms.     

The effect of estrus synchronization treatment on somatic cell count of transitional-anestrus local-Damascus cross breed goats’ milk

An experiment was conducted to examine the effect of estrus synchronization protocols and steroid hormones concentrations on somatic cell count (SCC) of transitional-anestrus local-Damascus cross goats’ milk. Fifty-six goats (2–4-year old) were randomly assigned to three groups: fluorogestone acetate (FGA, n = 19), FGA-Prostaglandin (FGA-PGF, n = 19) and control (n = 18) groups. Intravaginal sponge containing 40 mg FGA was inserted for 13 days and an injection of 600 IU equine chorionic gonadotropin (eCG) was administered for goats of FGA and FGA-PGF groups at the time of sponge removal (day 0). In addition, goats of FGA-PGF group were injected with 10 mg dinoprost tromethamine () on day 0. Five fertile local-Damascus cross bucks were turned-in with all goats on day 0. Blood and milk samples were collected from all goats on days -13 (beginning of experiment), -6, 0, 1, 2, 7, 13 and 20 (end of the experiment). Four-year old and second-parity goats had significantly higher (p < 0.05) SCC of both udder halves than 2- and 3-year old and first-parity goats, respectively. There was a significant effect (p < 0.05) for treatment and number of kids born in the last kidding season on SCC of both udder halves. Neither estradiol nor progesterone concentrations were correlated with SCC in goats in this experiment. The SCC of both udder halves and left udder halves in goats of the control and FGA groups, respectively, increased significantly (p < 0.05) after sponge removal and buck introduction when compared with day 0, with no differences in the FGA-PGF group. This increase in SCC of the control and FGA groups coincided with peak estrus behavior. However, SCC was far below the upper limit of the current standard for normal milk. In conclusion, induction of estrus with progestagen based programs and buck introduction may cause temporary significant increase in SCC. However, the SCC values during this period of temporary increase were still in the range of acceptable values for normal milk. With the current standards for SCC of 1,000,000/ml as legal limit for abnormal milk control programs in goats, estrus synchronization programs and the estrus status should not be considered when bulk-tank milk SCC is being investigated.     

Torsion of the uterus in an Awassi ewe

The treatment of a 4-year-old pluriparous Awassi ewe with torsion of the uterus at parturition is described. At presentation, all the signs of imminent parturition were present and the rostral portion of the vagina was spirally twisted to the right causing complete stenosis of the birth canal with no foetal fluid exiting the uterus. A 360 degrees clockwise uterine torsion was diagnosed. Attempted treatment by rotation of the ewe's body proved unsuccessful. The condition was then corrected surgically via a left flank caesarean operation, and a dead foetus and foetal membranes were removed. The animal made an uneventful recovery and the sutures were removed on the 12th postoperative day.