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Sixteen fertile rams were randomly allotted to four groups and fed either of the four diets for 14 weeks: (1) control diet (COD) without fish oil (FO) and vitamin C (VC), (2) diet containing 2.5% FO (FOD), (3) diet containing 300 mg/kg DM VC (VCD), and (4) diet containing 2.5% FO and 300 mg/kg DM VC (FCD). Semen was collected at 14-d intervals from 1 April to 10 July (out of the physiologic breeding season in Iran). Semen volume and percentages of motile and progressively motile sperm were increased by FO and VC feeding. A significant interaction was also found between FOD and VCD on motility and progressive motility percentage (P<0.05). HOS-test and percentage of sperm with normal acrosome improved significantly by FO and VC. Rams fed FCD had better HOS-test and higher proportion of sperm with normal acrosome than rams in other groups (82.4 and 93.6%, respectively). Diets containing FO and FO and VC increased the proportion of docosahexaenoic acid in sperm (P<0.05). The activity of lactate dehydrogenase in the seminal fluid was significantly affected by VC and the interaction between FO and VC (P<0.05). Blood metabolites, except glucose, were affected positively by FO. The results showed that dietary supplementation with FO and VC improved seminal quality and may have beneficial effects on fertility in Moghani rams., (Copyright © 2014 Elsevier B.V. All rights reserved.)

This study was conducted to investigate relationships between mitochondrial respiratory chain complex activities, feed efficiency, and carcass traits in sheep. A group of Ghezel male lambs sired by a single ram were randomly allotted to individual pens. The lambs were fed ad libitum with a fattening diet containing 30% roughage (corn silage and alfalfa hay) and 70% concentrate for 70 d to individually phenotype each lamb for feed conversion ratio (FCR), adjusted FCR (aFCR), and residual feed intake (RFI). The lambs were then humanely killed and the liver, abdominal fat, pelvic fat, cardiac fat, warm carcass weight, and cold carcass weight, as well as the cross-sectional area of the LM and the fat depth over the 12th rib, were determined. A portion of LM was obtained to determine mitochondrial protein and respiratory chain complex activities (complexes I to V). Statistical analysis was carried out based on lambs exhibiting high and low RFI (n = 8), FCR (n = 8), or aFCR (n = 8) phenotypes. The lambs exhibiting the high-RFI phenotype consumed 110 g more feed daily (P < 0.05) than did the phenotype exhibiting low RFI, with no difference in ADG. Conversely, there was no difference in feed intake between the low- or high-FCR groups, but sheep exhibiting the low-FCR phenotype gained 70 g more (P < 0.05) per day compared with those exhibiting the high-FCR phenotype. It was determined that all 5 respiratory chain complex activities were greater (P < 0.05) in sheep exhibiting the low-RFI phenotype compared with those exhibiting the high-RFI phenotype, with significant (P < 0.001) negative correlation coefficients between RFI and respiratory chain complex activity. When efficiency was assessed using FCR, only activities of respiratory chain complexes III, IV, and V were less (P < 0.05) in the low-FCR phenotype compared with the high-FCR phenotype, and there were no differences (P > 0.1) in respiratory chain complex activities between groups when FCR was adjusted for metabolic BW (aFCR). There were no differences (P > 0.1) in carcass traits among any of the feed efficiency phenotypes. The results suggest that the inclusion of respiratory chain complex activities in breeding programs may be helpful in selecting for sheep exhibiting the low-RFI phenotype.

Fifty four Mehraban ram lambs (6-to 8-month old, initial live weight 35.4 +/- 4.2 kg) were assigned to a completely randomized design consisting of 9 groups and were fed for 70 days with diets containing three levels of energy (2.3, 2.5 and 2.7 Mcal metabolizable energy per kg dry matter) and three levels of protein (10.5, 12.5 and 14.5 percentage in dry matter). Either energy or protein levels alone significantly affected most of the parameters of lamb performance, but their interaction effect was significant only for feed conversion ratio, cold carcass weight, tail weight, flap weight and back fat (subcutaneous fat) depth. The lowest level of energy (2.3 Mcal ME per kg DM) resulted in a significant decrease in lamb performance as compared with other energy levels. Increasing energy concentration of the diet resulted in significant increases in fat percentage, but significantly decreased the moisture and protein content of the Longissimus dorsi muscle. Increased dietary protein level increased the daily DMI and ADG and at the same time improved the FCR. Hot and cold carcass weights increased significantly with increasing dietary CP levels, but dressing percentage was similar amongst the dietary protein densities. Dietary CP levels had no significant effect on the chemical composition of the Longissimus dorsi muscle. At the lowest energy level (2.3 Mcal ME per kg DM), dietary protein level had a significant effect on FCR (Table 4); with the diet containing 10.5% protein having the highest FCR. At the medium and low energy levels the lowest level of dietary protein concentration resulted in smaller carcasses. The highest level of protein along with the medium energy concentration resulted in smaller tail weights. Flap weight was significantly smaller at low energy concentration along with medium and low protein level. The lowest back fat depth was found in lambs fed on the low energy diet containing medium to high levels of protein.

An experiment was conducted to study seasonal variations of thyroidal activity, serum testosterone concentration and seminal characteristics of two breeds of Iranian fat-tailed sheep. Eight 3 to 4-year-old rams of Ghezel and Mehraban breeds (4 rams/breed) were randomly selected from a flock of fertile rams. Semen was collected by using an artificial vagina, and blood samples were obtained via jugular vein. Seminal characteristics, scrotal length, width, and circumference, and blood parameters were measured at 3-week intervals. Time of the year significantly (P < 0.05) affected the volume of semen, sperm concentration, percent live sperm, percent normal sperm, total sperm number, seminal pH, seminal lactate dehydrogenase (LDH) concentration, scrotal circumference, scrotal width, and serum levels of testosterone, cholesterol, triiodothyronine (T(3)), tetraiodothyronine (T(4)), free T(4) index (FT(4)I), and TSH. Scrotal length was not affected by the time of sampling (P > 0.05). The effect of breed on the serum concentrations of hormones and cholesterol was not significant. Volume of semen, percent normal sperm, and total number of normal sperm were significantly (P < 0.05) higher in Mehraban but scrotal circumference, scrotal width and scrotal length were greater in Ghezel rams. Breedxtime interaction effect was significant for T(4), FT(4)I, sperm concentration, and total sperm number. The largest values for TSH, T(4), FT(4)I, testosterone, total sperm number, percent normal sperm, percent live sperm, sperm concentration, volume of semen and scrotal circumference were found from early summer to winter and the lowest values were recorded at the end of spring and in early summer. In both breeds, high and negative correlations (r = -0.7 to -0.8) were found between LDH levels in semen and percent live sperm, percent normal sperm and total sperm number (P < 0.01). It is unlikely that such variations in seminal quality would affect the fertility under natural mating.

Enzyme histochemical techniques were applied to frozen sheep uteri from different stages of the oestrous cycle. The localization and activities of succinate, lactate, glucose-6-phosphate, and isocitrate (NADP+) dehydrogenases and acid and alkaline phosphatases were studied in the luminal and glandular epithelia, caruncle and myometrium. Enzyme activity in the sections was scored on a scale of 0--5. In general the enzyme activity in the uterine caruncles and epithelia was higher than in the myometrium. The myometrium did not show any alkaline phosphatase activity and isocitrate dehydrogenase (NADP+) activity was negligible. The low activities of acid phosphatase and lactate dehydrogenase and the moderate levels of glucose-6-phosphate and succinate dehydrogenases in the myometrium were constant. The caruncular tissue showed high levels of phosphatases and glucose-6-phosphate dehydrogenase, moderate levels of lactate and succinate dehydrogenases, and low levels of isocitrate dehydrogenase (NADP+) throughout the oestrous cycle. Much lower phosphatase and isocitrate dehydrogenase (NADP+) levels were found in the epithelium of deep glands compared with superficial glands. The high activity of acid and alkaline phosphatases in the luminal epithelium and the superficial glands was constant from mid-cycle to ovulation, but a significant decrease was observed immediately after ovulation. The level of dehydrogenases in epithelia was generally high and did not change during the oestrous cycle.

Published data on the effects of essential oils (EO) on in vivo nutrient digestibility in sheep are contradictory. In 2 experiments, the effect of thymol and carvacrol on nutrient digestibility was studied in sheep fed with high (70%) or low (52%) concentrate diets, using incomplete Latin Square designs. The essential oils were mixed with the concentrate portion of the diet at the rate of 0.0, 0.3, or 0.6 g per kg dry matter (DM) diet. Supplementation of thymol had no significant effect on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and acid detergent fiber (ADF). The main effect of thymol on neutral detergent fiber (NDF) and ether extract (EE) digestibility and on nitrogen balance (NB) was significant (P<0.05), but within each level of dietary concentrate no significant differences were observed for these measurements. Overall, ruminal ammonia concentration was higher (P<0.05) in both HCD and LCD lambs receiving 0.3 mg thymol per kg diet. Supplementation of carvacrol had no significant effect on nutrient digestibility. The main effect of carvacrol on ruminal ammonia levels and NB was significant, but within each level of dietary concentrate no significant differences were observed in ammonia levels and NB. Inclusion of 0.3 g/kg diet DM of carvacrol or thyme was more effective than 0.6 g/kg diet DM in terms of NB but neither dose affected nutrient digestibility. Future research should determine the long-term effects of essential oils on digestibility and performance in sheep, before recommendation can be made for their use under practical husbandry conditions. [ABSTRACT FROM AUTHOR]

The effect feeding olive-pulp silage (OPS) for 120 days on several blood attributes was studied using 16 rams allotted to two diets consisting of 70% corn silage or 70% OPS. Olive-pulp silage feeding resulted in lower serum total protein, alanine aminotransferase, calcium and phosphorus levels and higher glucose concentration compared to the corn silage diet. Body weight and other blood attributes were not affected by OPS feeding. Feeding a diet containing 70% OPS at the maintenance level had no apparent detrimental effect in mature rams. [ABSTRACT FROM AUTHOR]

Halophyte forages originating from central Iranian deserts (Kochia scoparia, Atriplex dimorphostegia) were harvested at early bloom stage. The potential value of these forages occasionally is constrained by alteration of serum constituents and metabolic hormones of some ruminants. Nine Balouchi ewes (48±2 kg BW) were transferred to metabolism cages and randomly allocated to three dietary treatments [T 1: kochia + alfalfa (1:1), T 2: atriplex + alfalfa (1:1), T 3: alfalfa] in a Latin Square experiment with three periods (28 days periods). During the last 3 days of each period, samples of blood serum and urine were collected. There was no differences between treatments as serum levels of Mg and Na (P>0.05). Whereas, Serum Ca levels for T 1 (8.04 mg/dl) and T 2 (8.29 mg/dl) was lower (P<0.01) than that T 3 (9.19 mg/dl). Halophyte forages elevated serum cholesterol (P<0.01), thyroxine (P<0.001), and bilirubin (P<0.01). Ewes fed T 1 had the highest (P<0.01) blood serum activity of alanine aminotransferase (ALT) (34.8 U/l). The activity of Aspartate aminotransferase (AST) was increased in blood serum of ewes fed halophyte forages (P<0.05). The effect of treatments on blood serum glucose levels were different (P<0.05) and the linear relationship for the sampling time tend to be significant (P<0.08). The effect of treatments on blood serum urea N were completely different (P<0.0001), however there was no linear and quadratic relationship for the time of sampling. [ABSTRACT FROM AUTHOR]