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The present study aims were to determine the profiles of changes in progesterone (P4) and 17-β-estradiol (E2) in the peripheral blood of Markhoz goat (Iranian Angora) during estrous cycle, gestation, and parturition throughout natural breeding season. Gestation length averaged 145.3 ± 0.8 days, and the litter size was 1.1 ± 0.1. Birth weight ranged 2.4-2.8 and 1.5-2.5 kg in male and female kids, respectively. The mean estrous cycle lengths were 20.3 ± 0.4 and 20.9 ± 0.4 days for PGF(2α)-induced and natural cycles, respectively. Blood sampling was carried out daily during estrous cycle and weekly during gestation till parturition. E2 attained higher level (24.7 ± 2.15 pg mL(-1)) at estrus phase and dropped down to the lower level (18.80 ± 1.16 pg mL(-1)) within 3 to 4 days post-estrus. Concomitantly, P4 started to increase from the mean basal value of 0.5 ± 0.03 ng mL(-1) on day 0 to 6.88 ± 0.95 ng mL(-1) on day 6 of estrous cycle and reached the peak value of 12.8 ± 0.61 ng mL(-1) on day 12. From day 15, a decline was observed in P4 values till the end of the cycle. P4 remained at lower concentrations for 20-50 days of gestation, then increased and reached to its maximum level (13.51 ± 0.279 ng mL(-1)) in week 15 and returned again to its basal values within 1-2 weeks before parturition. The results will be discussed in terms of the usage of steroid hormone profile in several assisted reproductive technologies.

This study was made on the effects of a normal diet containing 12.8 mg Cu kg(-1) DM which added gradually molybdenum and sulphur on the copper status and fibre quality in eight 1-year Merghoze goat. One group (n = 4 mean weight 31 +/- 2.0 kg) was treated with Mo and S supplements for 20 weeks, the second group (n = 4 mean weight 32 +/- 2.1 kg) served as controls. In addition of blood sampling for measuring copper status in plasma, the copper content and quality of fleeces were measured every 6 weeks. Mohair measurements were carried out by taking patch samples (10 x 10 cm2) from the mid-side area of the goat. The analytical set consists of plasma copper concentrations (Pl Cu), Trichloroacetic acid soluble copper concentrations (TCA-Cu), and fleece copper content. The results indicated that the addition of 20-30 mg Mo and 2-2.5 g S kg(-1) DM to the normal diet did produce sub clinical copper deficiency in treated goats. One such visual symptom was the loss of fleeces pigmentation and poorer crimp being observed. The Pl Cu minus TCA-Cu plasma became more than 2 microM in the blood of treated goat, indicating that there was a significant thiomolybdate formation in the body. The results showed that there was a significant decrease in Pl Cu (p < 0.05) along with a significant increase in thiomolybdate (MoS) production after 4 months. The sub clinical signs of copper deficiency and mohair quality are likely to be from high molybdenum intake and thiomolybdate formation in the body.

One hundred female Markhoz goats (42±5 kg) were used to investigate the 'male effect' on estrous synchronization and reproductive characteristics of female goat during the breeding season. This was carried out in three separate experiments. In the first experiment, forty female goats were used in 4 groups with different distance from the male goats (i.e. source of pheromone secretion); A1 (1 meter), A2 (12.5 meters), A3 (25 meters) and A4 (50 meters). In the second experiment, thirty female goats were synchronized using CIDR in three groups in the presence or absence of male goats; B1 (the presence of male goat with females during synchronization), B2 (sudden introducing of male goat to females goat during the time of removal of CIDR) and B3 (no male goat during synchronization). In the third experiment, thirty female goats were used in 3 groups; C1 (male goat permanently was presented near to the females during the experiment), C2 (sudden introducing of male to females) and D or control group (no male before mating). The results showed the effect of male goat on estrous synchronization, causing reproductive cycles in early breeding season and increasing incidence of estrous (P<0.05). The male effect improved fertility and kidding rates (P<0.05). Male effect was more pronounced when the distance of unlike sexes decreased (P<0.01). Male effect was also more effective, with sudden introducing of male to female goat (P<0.01). The male effect was more efficient when compared with synchronized female by CIDR in onset of estrous (P<0.05), and increased serum estrogen concentration in the follicular phase (P<0.05). [ABSTRACT FROM AUTHOR]

Ten male Merghoz goats with initial live weights of 29.2 ± 1.2 kg (Mean±SE) were used to investigate the effect of natural changes in photoperiod on dry matter intake (DMI) and reproductive activity during a 365 day study. The bucks were housed in individual pens, under natural daylength condition at west of Iran, Kermanshah (34° 18' N and 47° 3' E and 1420 m above sea level). A diet was offered with an estimated concentration of metabolizable energy and crude protein of 7.9 MJ and 98.8 g per kg dry matter (DM) respectively. Live weight, DMI, and additive daily gain (ADG) of individual animals were recorded weekly. The serum testosterone concentrations were determined in blood samples collected at monthly intervals. During the observation period, semen was collected monthly with the aid of an electro-ejaculator and examined microscopically immediately after collection. The physical parameters of semen and the semen index were recorded. The sexual behavior and testicular size of goats were assessed monthly throughout the study period. The highest DMI was observed during summer (64.3±0.9 g/kg BW0.75) and spring (62.2±2.9 g/kg BW0.75) however, the lowest was recorded in the winter season (54.0±0.9 g/kg BW0.75). The seasonal values of ADG (g/d) ranked spring > summer > winter > autumn. Bucks demonstrated the highest sexual behavior in late summer and, thereafter during autumn, using the lower (P<0.05) number of mounts per ejaculation and a higher frequency (P<0.05) to sniff, approach, and vocalize a doe with estrous status. This was coincided with a higher (P<0.05) level of plasma testosterone (8-10.1 ng/mL) and the best semen quality (semen index: 744-989?106/mL) and quantity (semen volume: 1.1-1.2 mL per ejaculate), higher testis length (13.3- 14.7 cm) and width (6.0-6.1 cm) and scrotal circumference (32.2-35.5 cm). It is concluded that, in Merghoz bucks, the seasonal pattern of DMI and reproductive activity may be attributed to each other as well as photoperiod. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this study was to evaluate the effect of repeated administration of hCG on the follicular and luteal charactristics and serum progesterone concentrations in eCG-superovulated Merghoz does. The estrous cycles of 40 adult does were synchronized following a 12-day treatment with intravaginal sponges (Chronogest®), with 1000IU eCG injected 2 days prior to sponge removal. On the day of sponge removal (day 0), the females were randomly assigned to 4 treatments. The first group (h1; n =10), received an i.m. hCG injection (500IU; Pregnyl®) on the day 0. The second group (h2; n =10), received an i.m. hCG (500IU) injection on days 0 and 1, while the third group (h3; n =10) received i.m. hCG (500IU) on days 0–2. Does in the control group (n =10) did not receive any hCG treatment. Blood samples were taken on days 0, 1, 2, 5 and 8 and analysed for serum progesterone (P4) concentrations. Premature luteal regression was considered to have occurred if the P4 concentrations declined to less than 1ng/mL by day 8 following sponge removal. On day 8 goats were slaughtered and ovaries recovered for evaluation. In each case the CL''s were counted and classified according to their appearance – as normal or as regressing. According to the serum P4 concentration on day 8, 42.8% (3/7), 0% (0/8), 0% (0/7) and 0% (0/6) of the goats underwent premature luteal regression in the control, h1, h2 and h3 groups, respectively. The control group was the only group in which there was a significant increase in the number of regressing CL''s on day 8 (5.1±1.5; P <0.05). The characteristics of the CL''s, including the mean diameter and weight was greater (P <0.05) in the h2 and h3 groups, compared to the control group (10.9±0.7, 11.0±0.9 vs. 7.9±1.1mm and 640.0±101.4, 691.7±111.7 vs. 294.3±143.7mg, respectively). No differences (P <0.05) in the number of large follicles present on the ovaries were recorded on day 8 between the groups. However, the diameter of the large follicles present on the ovaries on day 8 was greater (P <0.05) in goats in the h2 and the h3 groups, compared to the control (15.3±0.6 and 12.9±0.3 vs. 8.6±1.7mm, respectively; P <0.05). The serum P4 concentrations were higher in the h2 and the h3 groups than in the control group on days 2 and 8. The serum P4 concentrations on day 8 also recorded a positive correlation with the normal CL''s, CL diameter and CL weight (P <0.001). These results indicate that the repeated administration of hCG post-sponge removal presumably prevents premature luteal regression and improves luteal function in goats after eCG-superovulatory treatment. However, neither the number of persistent follicles nor the diameter of the persistent follicles was reduced. [Copyright &y& Elsevier]

Abstract: The aims of the present study were to evaluate if seasonality in semen characteristics and plasma testosterone concentrations exist in Markhoz male goats. Ten Markhoz (Angora) bucks were housed and fed according to standard recognized practices. During the observation period, semen was collected monthly with the aid of an electro-ejaculator and examined microscopically immediately after collection. Physical parameters of semen and the semen index were recorded. Blood samples were also taken monthly throughout the observation period and the plasma testosterone concentration monitored. Bucks demonstrated a higher semen quality (P <0.05) in autumn and summer (semen index of 965×106 and 752×106 ml−1, respectively), compared to spring and winter (semen index of 606×106 and 512×106, respectively). This coincided with a higher (P <0.05) plasma testosterone concentration in autumn and summer (8.1 and 10.1ngml−1, respectively), compared to that obtained in spring (3.0ngml−1) and winter (2.5ngml−1). During autumn and summer, the ejaculate volume (average of 1.2 and 1.0ml), sperm output (1159×106 and 1005×106 spermml−1), sperm mass motility (4.2 and 4.3), sperm progressive motility (83.9 and 82.0%) and percentage live sperm (90.7 and 88.2%, respectively) of the bucks were higher (P <0.05) than in the spring (0.6ml, 880×106 spermml−1, 3.3, 71.5% and 80.2%) and winter (0.7ml, 863×106 spermml−1, 4.0, 71.5% and 84.9%, respectively). During autumn and summer, the percentage of sperm abnormalities (5.0 and 9.2%) was significantly lower than that in spring (12.9%) and winter (11.2%). The semen pH was slightly alkaline being significantly (P <0.05) lower in the autumn (7.1) than in spring (7.3). Data showed season of the year to influence all semen parameters evaluated—indicating that optimal buck performance may be obtained in late summer and autumn. It can thus be said that Markhoz bucks have distinct seasonal spermatogenic activity, with poorer semen characteristics being recorded during winter and spring. This may be a critical obstacle when implementing an intensive breeding system of three kidding seasons in 2 years, with natural mating being implemented. [Copyright &y& Elsevier]

Ten Scottish male castrated cashmere-yielding (C) and 10 Angora (A) goats with initial live weights of 38·2 (C) and 32·1 (A) kg respectively were used in a 112-day study in the time period August to December. The goats were blocked within genotypes according to live weight and randomly assigned to one of two treatments: either no supplementation (O) or dietary supplementation (S) with 2·5 g/kg dry matter (DM) intake of rumen-protected intestinally available methionine (Smartamine™ M, Rhone Poulenc, Animal Nutrition, Antony 92164, France) in a 2 × 2 factorial arrangement.The goats were offered a basal diet in the proportion of 0·6, grass hay and 0·4 concentrate according to their live weight. Diet metabolizable energy (ME) and crude protein (CP) concentration per kg DM were estimated as 9·9 MJ (ME) and 107 g (CP) and DM intake was restricted to 28 g/kg live weight daily. Apparent digestibility and nitrogen (N) balance studies were conducted from days 24 to 40 and 51 to 64. Measurements were made within three time periods of days 0 to 40, 41 to 75 and 76 to 112.Angora goats excreted less urinary N than cashmere-yielding goats and had lower values for plasma urea and glucose and greater overall retention ofN, associated with a two- to three-fold greater total fibre yield. Cashmere as a proportion of total fibre by weight, (guard hair plus cashmere) varied from 0·27 to 0·43.The main effects due to methionine supplementation were improvements in live-weight gain and food conversion ratio. Reductions in urinary N excretion and increases in N retention were recorded, which were generally greater for Angora than for cashmere-yielding goats, and were again associated with the larger responses in fibre production. Clear evidence was also obtained for methionine-induced increases in the weight of raw cashmere, although not guard hair up to day 58. This response was obtained in the absence of significant effects on cashmere diameter, although methionine supplementation consistently increased the average diameter of mohair fibres. [ABSTRACT FROM PUBLISHER]

This study was conducted to determine the effects of organic and inorganic selenium (Se) supplementation during late pregnancy on serum Se status, colostrum, performance and passive immunity in Merghoz goats in Iran. Thirty Merghoz goats (30 ± 3 kg) were given the same basal diet containing 0.11 mg Se/kg DM and were randomly allocated to one of three dietary treatments in a randomised complete block design. Four weeks before the expected kidding, the basal diets were supplemented with 0 (control), 0.3 mg Se/head.day in the form of L-selenomethionin (Se-Met) and 0.3 mg Se/head.day in the form of sodium selenite. Blood samples were collected from the goats in three phases: (1) a couple of days before starting the supplementation; (2) before the expected kidding; and (3) on the day of kidding. Blood samples were also taken from the newborn kids from the jugular vein at birth and 7 days of age. The serum Se and immunoglobulin G (IgG) concentrations, the white blood cells (WBC) and differential leukocyte counts were measured. The reproductive parameters such as the number of kids born per kidding, total weight of kids born per goat mating, the pregnancy period and kid birthweights were determined. The results indicated that the serum Se concentration increased in supplemented goats compared with controls. The Se concentrations also significantly increased in the colostrum of treated goats (P < 0.05). Similarly, serum Se concentrations in kids of treated goats were increased at birth. On the other hand, colostrum and daily milk production were not affected by Se supplementation. Likewise, the change in the mean serum IgG levels was not different among goats and kids (P > 0.05). However, the WBC, neutrophil and lymphocyte counts were higher in the kids of goats in the Se-Met group compared with the control group on the day of birth and 7 days of age (P < 0.05). It seemed that Se-Met could have influenced the lamb's immunity at birth and 7 days of age. By contrast, selenite has not affected the performance and passive immunity in Merghoz goats. Organic and inorganic Se supplementation would be useful for producers who raise animals in Se-deficient regions. There is higher efficiency of L-selenomethionin (Se-Met) than the sodium selenite (SS) supplement. The kids with adequate levels of Se obtain more maternal antibodies in colostrum. Both Se supplementations in pregnant goats improved Se status of goats and the newborn kids. The Se-Met supplement could have influenced passive immunity of kids. [ABSTRACT FROM AUTHOR]

Abstract: The present study aims to determine the effect of dietary Se supplement on Merghoz goats at the last stage of gestation on serum Se, Cu, Zn and Fe status of goats and their kids. Thirty Merghoz does (30±3kg) were fed the same basal diet containing 0.11mgSekg−1 DM and randomly assigned to one of three dietary treatments in a randomized complete block design. Three weeks before the expected kidding, the basal diet was supplemented with 0 (control) or 0.3mgSehead−1 d−1 in the form of l-selenomethionin (Se-Met) and 0.3mgSehead−1 d−1 in the form of sodium selenite (SS). Blood samples were collected from the does three weeks before the expected kidding and on the kidding day. Blood samples of newborn kids were also taken from the jugular vein at birth and 7 days of age. The results indicated that the serum concentration of Se increased in supplemented does compared with the control ones. The selenium concentration was also significantly increased in colostrum of treated does (P <0.05). There was no significant difference between Se sources on the Se status although there was higher efficiency of Se-Met than sodium selenite supplement. The serum concentration of copper increased in supplemented doses, which was concomitant with a reduction in Zn concentration in serum and colostrums. It seems that an increase in serum concentration of Cu at the end of pregnancy in goats given Se supplement could disturb the Zn:Cu ratios which in turn lead to Zn reduction. Serum Se, Cu and Fe concentrations of kids of treated doses increased at birth and first week of age, while the serum concentration of Zn decreased in newborn kids. It seemed that there was a positive correlation between serum Se concentration with Cu and Fe levels and also a negative correlation between Se and Zn in treated dose (P <0.05). [Copyright &y& Elsevier]