The present study aimed to investigate the enzymatic and antioxidant activities as well as lipid profile in the seminal plasma of good and poor freezer Arabian stallions, to determine if any of the studied seminal plasma constituents were associated with semen freezability. Semen samples were collected from 10 Arabian stallions (5 stallions were previously classified as good freezers and the other 5 stallions were poor freezer). After collection, fresh semen characteristics (including volume, sperm concentration, motility, morphology, membrane and acrosomal integrities) were recorded. Semen samples were processed for freezing and post-thaw semen evaluation was performed. Seminal plasma was obtained by semen centrifugation and filtration of the supernatant. Nitric oxide, antioxidant, enzymes and testosterone levels as well as lipid profile were determined in seminal plasma samples.
Results showed that, the HOS (hypo-osmotic swelling test)-positive spermatozoa in fresh semen, antioxidant activities, testosterone, cholesterol and phospholipid levels were significantly (P ≤ 0.05) higher in seminal plasma of good freezer stallions than in that of poor freezers. On the other hand, nitric oxide, aspartate-amino-transferase (AST), alanine-amino-transferase (ALT) and alkaline phosphatase levels and cholesterol/phospholipid ratio were significantly (P ≤ 0.05) lower in seminal plasma of good freezer stallions than in that of poor freezers. There were significant (P ≤ 0.05) positive correlations between equine semen freezability and sperm membrane integrity (according to results of HOS test), antioxidant activities, cholesterol and phospholipid levels (‘r’ ranged from 0.595 to 0.895). Contrarily, there were significant (P ≤ 0.05) negative correlations between equine semen freezability and nitric oxide level and cholesterol/phospholipid ratio. Conclusively, the HOS test applied on fresh semen, the levels of nitric oxide, superoxide dismutase and glutathione peroxidase in the seminal plasma as well as the cholesterol/phospholipid ratio were correlated well with freezability of equine semen. So, they could be used as biomarkers for frrezability of Arabian horse’s semen.

Abstract
The present study aimed to maximize the semen output from rams using oxytocin, prostaglandin F2α (PG F2α) or gondatrophin releasing hormone (GnRH) as well as to study the effects of these treatments on quality, freezability and antioxidant activity of ram semen. In the present work, 4 groups (each containing 3 Barki rams) were used as; control (group 1) injected with normal saline intramuscularly (i.m.) 30 min. prior to semen collection, group 2 injected with 10 i.u. oxytocin intravenously (i.v.) 10 min. prior to semen collection, group3 injected with 250 µg of cloprostenol i.m. 30 min. before semen collection and group 4 injected with 50 µg of gonadorelin i.v. 60 minutes before semen collection. Two ejaculates were collected from rams of all groups once weekly for 10 successive weeks. At the 1st, 5th and 10th week semen samples were processesed for cryopreservation and testosterone and antioxidant enzymes were measured in the separated seminal plasma. Results indicated that both PG F2α and oxytocin resulted in significant (P ≤ 0.05) increase in semen volume and total number of spermatozoa per ejaculates allover the experimental period without altering the quality of the fresh ejaculated or the frozen-thawed semen. Also, PG F2α and oxytocin had no undesirable effect on testosterone level and the values of total antioxidants, superoxide dismutase and glutathione peroxidase in seminal plasma. On the other hand, GnRH elevated the level of testosterone but did not increase the sperm output in rams. Conclusively, repeated injection of PGF2α and oxytocin prior to semen collection was found to be useful when collecting ram semen for use in artificial insemination as they increase the sperm output without altering the quality of fresh or frozen-thawed semen as well as they have no deleterious effects on the antioxidant activities of seminal plasma and testosterone level in rams.

This study hypothesize that some metabolic hormones increase during clinical endometritis and modulate immune responses to combat this inflammation in mares. 45 mares of different ages were used. Mares were examined by ultrasound and underwent weekly blood sampling from the day of estrus detection till determination of early pregnancy. Mares were classified according ultrasound examination into early pregnant mares (N=16), non-lactating during estrus (N=17), clinical endometritis (N=3) and lactating during foal heat (N=9). Blood serum leptin, IGF-I, T3, T4, estradiol, progesterone, testosterone were assayed using commercial ELISA kits. Copper, zinc and iron was measured using Atomic Flame absorption spectrophotometer. Nitric oxide (NO) was measured calorimetrically using spectrophotometer. Results of this study showed that mares with endometritis days 7-14 after ovulation had significantly high IGF-I (P=0.0001) and T4 (P=0.009), low progesterone (P=0.0001) and NO (P=0.18) compared to those cyclic without clinical endometritis or early pregnant mares and insignificantly (P=0.74) slight increase in leptin. A direct significant (P<0.05) correlation existed between IGF-I and NO (P=0.02), between IGF-1 and T4 (P=0.05) and between leptin and testosterone (P<0.05) but an inverse relation existed between T4 and Estradiol (P<0.01) and Estradiol and testosterone (P<0.01). Inverse non significant (P>0.05) correlations existed between NO and leptin. This study proved our assumption that leptin, IGF-I and thyroxin increase during mare endometritis to combat inflammation beside their physiological role during estrus, ovulation, and early pregnancy.

This study describes difference in thyroid hormones and sex hormones in pregnant and non pregnant camels. Female camels (n=12) of different ages brought from Sudan and belonged to a private camel farm underwent rectal ultrasound scanning for detection of early pregnancy. Male and females were kept together in the same barn during the breeding season. Blood was collected and subjected to hormonal analysis. Estradiol, progesterone, testosterone, T3, and T4 Insulin were assayed. Results revealed that levels of T3 and T4 were significantly high in pregnant camels. While, low significant T4:T3 was observed in pregnant camels. Progesterone levels significantly increased in pregnant camels and its values ranged from 2.83 to 6.89 ng/ml. Both testosterone and estradiol slightly increased during early pregnancy. In conclusion, progesterone still the most important confirmatory hormone for detecting pregnancy in camels even thought after the advent of ultrasound examination because pregnancy can't be detected by either trans-rectal ultrasound or rectal palpation beyond 90 days of gestation. It appeared that thyroid hormones play important role during camel's gestation.

Summary
This study was conducted to evaluate the effect of probiotic supplementation to ewes previously exposed to under nutrition on DNA fragmentation, enzymatic and, non enzymatic antioxidant as well as some hormones and biochemical parameters. Fifteen sexually mature local ewes of 2-3 years old during the breeding season in a private farm at Giza Governorate. Ewes were used in the current study free from any infectious diseases and external parasites. All ewes were synchronized by impregnated sponge divided into three groups.The first group under nutrition group, second group re-fed on balanced ration and third group re-fed on balanced ration supplemented with Ru-max 3gm/head /day for two months, one month before synchronization and one month after. Blood samples were collected at zero day and 9 day of estrous cycle to investigate DNA fragmentation percentage, the oxidative stress and some hemato- biochemical changes
Hematological examination showed significant increase in RBCs count, Hb, PCV. and TLC at (p<0.05) in ewes supplemented with proboitics compared to other groups . There is a significant decrease at (P<0.05) in DNA fragmentation percentage and bands intensities accompanied by significant decrease of lipid peroxidase activity and nitric oxide with significant increase in the activities of the glutathione–S-transferase ,SOD and catalase (enzymatic antioxidant ) and vitamins (A,C,E) and trace elements copper , zinc, selenium and iron (non enzymatic antioxidant) in probiotics supplemented ewes compared to other group Probiotic supplementation significantly increased at (P<0.05) total protein, albumin , globulin and glucose concentrations accompanied by non significant difference between groups in serum urea creatinine, ALT and AST. There was a significant increase p (<0.05) of blood insulin and reproductive hormones in probiotics supplemented ewes than other groups, also, there was significant improve in level of progesterone and estradiol hormones of probiotics supplementation at p (<0.05) .
In conclusion, addition of Ru-max as a biological feed additives to the ewes in case of stress due to under nutrition had positive and beneficial effects to enhance digestion and nutritive values, rumen fermentation, while it suppress oxidative stress which consequently decrease fragmentation of DNA and improved ovarian activity by its positive effects on metabolic hormones and blood constituents without any adverse effect on either liver or renal functions

SUMMRY
The present study was determined the effect of combined mycotoxins caused by Aflatoxin and zearalenone exposure on reproductive performance and their relation to the incidence of ovarian cysts in dairy cattle. The present study used 28 lactating cows kept at dairy farm in Dakahlia governorate. Cows were classified into two groups First group (10 cows) were received ration where the percentage of aflatoxin and zearalenone not exceed permissible limit which is (5 ppb and 200 ppb respectively) and show normal estrous behavior and have mature large follicles >22mm<25mm in diameter and have corpus luteum .The second group (18 cows) received ration containing aflatoxin which found exceed permissible limit (19.7 ppb).and zearalenone which was present at high levels (400 ppb) ,these cows exhibit“constant” estrus (nymphomania), excessive vaginal discharge, until day 45 postpartium.and have ovarian cysts based on the presence of follicular structure( ≥25 mm in diameter) with anovulation and the absence of corpus luteum
. Blood samples was collected from each cow around 45 days postpartium for evaluation of serum progesterone (P4),estrogen (E2) ,Luteinizing hormone (LH), triiodothyronine (T3), thyroxin(T4),prolactin(PRL) total protein , calcium , inorganic phosphorus, Liver enzymatic activities alanine aminotransferase (ALT) and aspartate aminotransferase (AST) immunologlobins ( IgG, IgM, IgA ). The results of hormonal assay showed significant increase (p<0.05) in levels of prolactin and estrogen, while levels of LH, progestone, T3 and T4 showed significant decrease (p<0.05) in cows received contaminated ration with zearalenone and aflatoxins in compared with control one. Regarding to results of biochemical and immunological parameters revealed a significant increase (p<0.05) in enzymatic activities (AST), (ALT), while total protein, calcium, inorganic phosphorus and immunological parameters (IgG, IgM, IgA) showed significant decrease (p<0.05) in cows received contaminated ration with zearalenone and aflatoxins compared with control one. Our results using transrectal ultrasonography revealed that mean diameter of follicular cyst was 42.3±3 mm of cows received contaminated ration with zearalenone and aflatoxins while mean diameter of mature follicles was 22.1±1.7 mm of control cows.
We concluded that zearalenone have been shown to competitive bind to oestrogen receptors and affect reproductive performance generating hormonal imbalance inducing cell toxicity , immunosuppression due to the combined effect of aflatoxins which may predispose cows to the incidence of ovarian cysts.

The human and bovine Iacteferrin have been Studied extensively, but very few reports have been published concerning comel lactoferrin ( clf ) .The present Study aimed to isolate cLF and evaluate its efficiency including antimicrobial activ ity and immunomodulator effects. cLfisolation was attempted from camel milk whey using a cation exchange chroma tography by Sp-SepharOSe The anitimicrobial activity of the isolated clf