Stallions were subjected to a gradually increasing photoper iod beginning on October 15, 1973. The maxi,mum artificial daylength (16 hr) was imposed on February 8, 1974, and maintained until October 6, 1974. Two ejaculates were collected from each of five treated and four control stallions weekly, with an interval of 24 hr between the paired ejaculates on the first and alternate weeks, and an interval of 1 hr on the second and alternate weeks. During summer, stallions subjected to the artificial photoper iod produced less (P<.05) gel-free semen and gel per ejaculate and had more (P<.05) spermatozoa per ml of gel-free semen than untreated stallions. Consistent differences due to artificial photoper iod were not observed for spermatozoa per ejaculate or percentage of motile spermatozoa. Light t reatment did not affect mounts per ejaculate or seminal pH, but stimulation time was reduced (P~.05) in treated stallions during late winter. Mean concentration of LH in the serum of untreated stallions varied (P<.01) over t ime and appeared to be highly seasonal. A corresponding change in concentration of testosterone was not observed (P>.05). Mean concentrations of both LH and testosterone were greater (P<.05) in the serum of treated stallions than in

This paper identifies a conceptual process describing how owner/managers of small and medium-sized enterprises undertake innovation in marketing. A model is presented which identifies seven elements in the process including the drive for profits. The process was derived from previously published research and further developed from a series of interviews, literature research, focus groups and analyses. The model in effect describes what ownermanagers practice. Recent academic research however presents another view, that the need for profit should really be a drive for costs as the prime focus of the owner-managers. This difference between the perception of profit compared to costs is an opportunity for further research.

A series of five factorial arranged experiments were conducted to investigate the effect of different management during semen collection on the microbial quality (bacterial load, type of microbes and frequency of isolation) of dromedaries’ semen. Microbial analysis of seventy-nine fresh ejaculates from twenty-two camels showed the presence of nine variant colonies. The most prevalent organisms in the dromedary semen were species of Staphylococcus, Bacillus and Streptococcus. One yeast species was represented among the isolates. The middle aged camels (9–13 years) had significantly (P > 0.05) higher mean bacterial loads than young (4–8 years) and old aged (14–18 years) animals. The mean bacterial populations of ejaculates collected by an electro-ejaculator were significantly (P > 0.05) higher than those collected by an artificial vagina. Candida spp. was identified in 53.8% of the samples collected by an electro-ejaculator and was not detected in ejaculates collected by an artificial vagina. The mean semen bacterial load detected during the breeding season was significantly (P < 0.01) higher than that collected during the non-breeding season. No fungi were isolated from semen samples collected in the non-breeding season. The difference between the mean semen bacterial loads in the first and the second ejaculate was highly significant (P < 0.01). The preputial wash significantly (P < 0.01) reduced the bacterial load. This study revealed that the microbial contamination of dromedaries’ semen is found in different intensities during different management procedures of semen collection.

In this study, the Authors investigated the modulatory effect of three single doses (10−6, 10−5, and 10−4 M) of neostigmine on the spontaneous contractility of equine pre-ovulatory follicles in an isolated organ bath, to establish the relationship between this acetylcholinesterase inhibitor and ovulation, in the mare. The results indicate that neostigmine increases pre-ovulatory contractility in equine follicles at each dose, but in a different manner. Indeed, the rise in contractility induced by neostigmine at 10−6 M and 10−4 M was phasic, while at 10−5 M it was tonic. The data obtained indicate possible implications of these drugs in the pharmacological modulation of equine ovulation.

Breeding records were analyzed from 24 Thoroughbred stallions that were subjected to dual-hemisphere breeding (DH), including novice (first-year; NOV; n = 11) and experienced (EXP; n = 13) stallions. Fertility variables included seasonal pregnancy rate, pregnancy rate per cycle, and first-cycle pregnancy rate. In addition, values for book size, total number of covers, distribution of mare type (maiden, foaling, and barren) within a stallion's book, cycles per mare, and mare age were examined. Some data were also categorized by mare type (maiden-M, foaling-F, and barren-B). Five separate analyses of the data were performed. For Analyses 1–3, the effects of hemisphere (northern hemisphere [NH] vs. southern hemisphere [SH]) and breeding order (refers to the first [O1] or second [O2] season within the first year of dual-hemisphere breeding) were examined for all stallions (combined group [CG]), NOV stallions only, and EXP stallions only, respectively. Fertility values were generally higher in the SH than the NH (P < 0.05), whereas book size, total number of covers, and cycles per mare were higher in the NH than the SH (P < 0.05). Book size and total covers were negatively correlated to first cycle pregnancy rate (r = −0.57, r = −0.71, respectively; P < 0.05) for NOV stallions. Pregnancy rate per cycle was also negatively correlated with total covers (r = −0.58; P < 0.05) for NOV stallions. Similar trends were noted for Groups CG and EXP, but the relationship was not as marked as for NOV stallions. The fertility of O1 was generally similar to O2 (P > 0.05).For Analysis 4, fertility of DH breeding seasons was compared to single hemisphere (SIN) breeding seasons within the same 16 stallions and was found to be similar between the two groups (P > 0.05). For Analysis 5, the effect of the number of consecutive DH breeding seasons on fertility was examined and was found to remain unchanged (P > 0.05).In summary, no adverse effects of DH breeding on fertility were detected. Fertility was higher when stallions were bred in the SH, as compared to the NH. Potential reasons for higher fertility achieved in the SH were smaller book sizes and better mare reproductive quality.

In this study, we tested the hypothesis that insemination of mares with twice the recommended dose of cooled semen (2 × 109 spermatozoa) would result in higher pregnancy rates than insemination with a single dose (1 × 109 spermatozoa) or with 1 × 109 spermatozoa on each of 2 consecutive days. A total of 83 cycles from 61 mares was used. Mares were randomly assigned to 1 of 3 treatment groups when a 40-mm follicle was detected by palpation and ultrasonography. Mares in Group 1 were inseminated with 1 × 109 progressively motile spermatozoa that had been cooled in a passive cooling unit to 5 °C and stored for 24 h. A second aliquot of semen from the same collection was stored for an additional 24 h and inseminated at 48 h after collection. Mares in Group 2 were inseminated once with 1 × 109 progressively motile spermatozoa that had been cooled to 5 °C and stored for 24 h. Group 3 mares were inseminated once with 2 × 109 progressively motile spermatozoa that had been cooled to 5 °C and stored for 24 h. All mares were given 2500 IU iv hCG at the first insemination. Pregnancy was determined by ultrasonography 12, 14 and 16 d after ovulation. On Day 16, mares were administered im 10 mg of PGF2α and, upon returning to estrus, were randomly reassigned to a group for repeated treatment. Semen was collected from one of 3 stallions every 3 d; mares with a 40-mm ovarian follicle were inseminated with semen from the stallion collected on the preceding day. Semen was allocated into doses containing 1 × 109 progressively motile spermatozoa, diluted with dried skim milk-glucose extender to a concentration of 25 × 106 motile spermatozoa/ml (total volume 40 ml), placed in a passive cooling unit and cooled to 5 °C for 24 or 48 h. Response was measured by number of mares showing pregnancy. Data were analyzed by Chi square. Mares inseminated twice with 1 × 109 progressively motile spermatozoa on each of two consecutive days had a higher pregnancy rate (16/25, 64%; P < 0.05) than mares inseminated once with 1 × 109 progressively motile spermatozoa (9/29, 31%) or those inseminated once with 2 × 109 progressively motile spermatozoa (12/29, 41%). Pregnancy rates did not differ significantly (P > 0.10) among stallions (69, 34 and 32%). Interval from last insemination to ovulation was 0.9, 2.0 and 2.0 d for mares in Groups 1, 2 and 3, respectively. Based on these results, the optimal insemination regimen is a dose of 1 × 10 progressively motile spermatozoa given on two consecutive days. However, a shorter interval (≤24 h rather than >0.9 d) between insemination and ovulation may affect pregnancy rates, and needs to be investigated.

Ten stallions were used in a modified split-plot design involving four treatments and two handling methods. Treatments were: a) vision and olfaction not blocked; b) vision blocked, olfaction not blocked; c) vision not blocked, olfaction blocked; and d) vision and olfaction blocked. The methods of handling were: a) stallions turned loose in teasing area, and b) stallions handled on a lead shank, Stallions teased four estrous mares, four diestrous mares and four geldings. Criteria for evaluation of stallion behavior was duration of investigation (sec), of area as well as various portions of the stimulus animal's anatomy, and other pre-copulatory sexual behaviors (Table 1) in duration and frequency. Except for area investigation and no investigation, there were more frequent or longer responses when vision was not blocked compared to blocked (P<0.05). Events associated with display of flehmen and mounting activity were lower (P<0.05) when vision was blocked. Handling a stallion on a lead shank, while teasing, resulted in 23 longer or more frequent pre-copulatory sexual behaviors than when the stallions were loose. There were more frequent or longer (P<0.05) behavioral responses when stallions were handled on a lead shank and olfaction was not blocked. Events such as duration and number of flehmen responses were lower (P<0.05), and time of no investigation was longer (P<0.001) when olfaction was blocked. There was no difference (P>0.05) in the time spent investigating estrous mares, diestrous mares or geldings, except for number of flehmen responses. Number of flehmen responses to estrous mares was higher (P<0.05) than to diestrous mares, while number of flehmen responses to diestrous mares was higher (P<0.001) than to geldings. Blocking olfaction did not decrease frequency or duration of sexual behaviors as much as blocking vision (P<0.05), resulted in decreased (P<0.05) flehmen responses. Blocking vision significantly decreased (P<0.05) teasing behaviors. duration of erection, flehmen, and number of mounts regardless of stimulus animal. Stallions utilized visual stimuli to a greater extent than olfactory stimuli. Handling stallions on a lead shank appeared to enhance expression of precopulatory behavior compared to when the stallions were loose.

Five experiments were conducted to evaluate damage incurred in each processing step for cryopreservation of stallion spermatozoa. In Experiment 1, semen was centrifuged for 9 centrifugation times and the percentage of spermatozoa recovered after each treatment was calculated and spermatozoal motion characteristics analysed. Recovery of spermatozoa was > or = 80% when spermatozoa were centrifuged for > or = 10 min. Experiment 2 evaluated spermatozoa cryopreserved at 5 different concentrations in each of 2 extenders (skim milk-egg yolk-glycerol, SM-EYG; and lactose-EDTA, LAC). In SM-EYG, TMOT and PMOT were higher at spermatozoal concentrations of 20, 200 and 400 x 10(6)/ml (51%/41%, 52%/44%, 50%/43%, respectively) than for samples frozen at > or = 800 x 10(6) spermatozoa/ml (41%/35%, 32%/27%; P < 0.05). Spermatozoa frozen in LAC at a concentration of 20 x 10(6)/ml resulted in the highest TMOT and PMOT (43% and 30%, respectively, P < 0.05). The effect of freezing rate on motion characteristics of spermatozoa was evaluated in Experiment 3. The VCL of spermatozoa frozen in SM-EYG was the only parameter affected by freezing rate (P < 0.05). Experiment 4 evaluated motion characteristics after cryopreservation of spermatozoa in different sized straws (0.5 or 2.5 ml) in each of 2 extenders (SM-EYG and LAC). In SM-EYG, PMOT (38%) and VCL (109 microns/s) were highest when spermatozoa were frozen in 0.5 ml straws (P < 0.05). In Experiment 5, spermatozoa thawed immediately after cryopreservation or thawed after storage in liquid nitrogen for 24-48 h were evaluated. There was no effect of length of storage in liquid nitrogen on spermatozoal motion characteristics (P < 0.05). Experiment 6 evaluated the effects of cooling time to 5 degrees C (0, 2.5 and 5 h) on motion characteristics of spermatozoa cryopreserved in 2 extenders (SM-EYG and LAC). TMOT and PMOT were effected by cooling time, and there was a cooling-time-by-extender interaction (P < 0.05). In SM-EYG, TMOT and PMOT were higher if spermatozoa were cooled to 5 degrees C prior to initiation of freezing than if freezing was initiated at 20 degrees C (P < 0.05). A suggested protocol for cryopreservation of stallion spermatozoa would include: 1) centrifugation at 400 g for 14 to 16 min; 2) extension at 23 degrees C with SM-EYG to 400 x 10(6) spermatozoa/ml; 3) cool to 5 degrees C for 2.5 h; 4) package in 0.5 ml straws at 5 degrees C; 5) freeze in liquid nitrogen vapour at -160 degrees C; and 6) thaw for 30 s in 37 degrees C water.

Four experiments were conducted to determine the effects of egg yolk (EY) and liposomes (L), composed of phosphatidylserine and cholesterol, on the motion characteristics and fertility of cooled or frozen-thawed stallion spermatozoa. In experiment 1, spermatozoa were diluted, centrifuged at 23°C, and resuspended to 30 × 106 cells/ml in one of four extenders: 1) skim milk (SM); 2) SM + L (SML); 3) SM + EY (SM-EY); or 4) SM + EY + L (SM-EYL). Motion characteristics of spermatozoa were evaluated after 1) resuspension following centrifugation, 2) cooling to 5°C and storage for 24 h, and 3) storage for 24 h at 5°C followed by 3-h incubation at 37°C. After cooling for 24 h, motility of spermatozoa in SM-EY (45%) and SM-EYL (44%) was higher than for spermatozoa in SM or SML (27 and 29%, respectively). In experiment 2, fertility of spermatozoa cooled to 5°C and held for 24 h in SM-EY or SM-EYL was compared. Fertility rates measured by embryo recovery 7 days after ovulation for mares inseminated with 600 × 106 spermatozoa diluted with the SM-EY and SM-EYL extenders were 69% and 64%, respectively (p > 0.05). In experiment 3, postthaw motion characteristics of cryopreserved spermatozoa in SM-EY and SM-EYL containing 4% glycerol (G; SM-EYG and SM-EYLG, respectively), were studied. Spermatozoa were processed as described in experiment 1, with the following exceptions: 1) spermatozoa were cooled faster to 5°C at −0.1°C/min, 2) a spermatozoal concentration of 200 × 106 cells/ml was used, and 3) spermatozoa were frozen in 0.5-ml straws over liquid nitrogen vapor. Treatment effects were not significant (p < 0.05). Experiment 4 compared fertility of fresh and frozen semen. Pregnancies at 20-40 days postovulation were similar for mares inseminated with spermatozoa frozen in SM-EYLG and for insemination with fresh semen (50 and 69%, respectively); both rates were higher than for spermatozoa frozen in SM-EYG, (17%; p < 0.05). Thus, addition of EY to an SM extender was beneficial for spermatozoa stored at 5°C and the combination of L plus EY improved fertility of cryopreserved spermatozoa.

Motion characteristics of cooled stallion spermatozoa in 2 freezing extenders were studied. Ejaculates from 8 stallions were split into treatments and cooled in thermoelectric cooling units at each of 2 rates. Cooling started at 37 °C for Experiments 1 and 3 and at 23 °C for Experiments 2 and 4, at a rate of −0.7 °C/min to 20 °C and from 20 to 5 °C, at either −0.05 °C/min (Rate I) or −0.5 °C/min (Rate II). Percentages of motile (MOT) and progressively motile spermatozoa (PMOT) were determined at 6, 24 and 48 h. Treatments in Experiment 1 were modified skim milk extender (SM); SM + 4% egg yolk (EY); SM+4% glycerol (GL); and SM + 4% egg yolk + 4% glycerol (EY + GL). At 24 and 48 h, MOT and PMOT were lowest (P < 0.05) for spermatozoa extended in SM + EY; spermatozoa in SM + GL had the highest MOT and PMOT. Thus, glycerol partially protected spermatozoa against the effects of cooling after long-term storage. Treatments in Experiment 2 were SM, semen centrifuged and pellet resuspended in SM (SMc), SM + EY, and semen centrifuged and pellet resuspended in SM + EY (EYc). Spermatozoa in SM + EYc had the highest (P < 0.05) PMOT at 24 h and MOT and PMOT at 48 hours. Spermatozoa in SM + EY (not centrifuged) had the lowest MOT and PMOT at 24 and 48 h, respectively. There was a detrimental interaction between egg yolk and seminal plasma. Extenders in Experiment 3 were Colorado extender (CO3), C03 + 4% egg yolk (EY), CO3 + 4% glycerol (GL), and CO3 + 4% egg yolk + 4% glycerol (EY + GL). Spermatozoa in CO3 + EY had the lowest (P < 0.05) PMOT at 24 and 48 h. CO3 did not protect spermatozoa cooled in the presence of seminal plasma. Therefore, in Experiment 4 we tested CO3 with seminal plasma present (control) and semen centrifuged and pellet resuspended in CO3 (CO3c), CO3 + EY (EYc), CO3 + GL (GLc) and CO3 + EY + GL (EY + GLc). Spermatozoa in CO3 had the lowest (P < 0.05) MOT and PMOT at all time periods, which suggested a detrimental interaction of this extender with seminal plasma.

Three experiments were conducted to evaluate the effects of egg yolk and(or) glycerol added to a nonfat dried skim milk-glucose (NDSMG) extender on motion characteristics and fertility of stallion spermatozoa. In Experiment 1, ejaculates from each of 8 stallions were exposed to each of 4 extender treatments: 1) NDSMG, 2) NDSMG + 4% egg yolk (EY), 3) NDSMG + 4% glycerol (GL), and 4) NDSMG + 4% egg yolk + 4% glycerol (EY + GL). Samples were cooled at −0.7 °C/min from 37 to 20 °C; subsamples were then cooled at −0.05 or −0.5 °C/min from 20 to 5 °C. Percentages of motile spermatozoa (MOT) and progressively motile spermatozoa (PMOT) were determined at 6, 24 and 48 h after initiation of cooling. There was no overall effect (P > 0.05) of cooling rate. PMOT was highest (P < 0.05) for spermatozoa extended in NDSMG + GL at 48 h. At 24 and 48 h, MOT and PMOT were lowest (P < 0.05) for spermatozoa extended in NDSMG + EY. In Experiment 2, ejaculates from 8 stallions were exposed to each of 4 treatments: 1) NDSMG, 2) NDSMG + EY, 3) semen centrifuged in NDSMG and resuspended in NDSMG, and 4) semen centrifuged in NDSMG and resuspended in NDSMG + EY. Samples were cooled from 20 to 5 °C at each of 2 rates (−0.05, −0.5 °C/min). A detrimental interaction between seminal plasma and egg yolk was noted for PMOT at 6 h and for both MOT and PMOT at ≥24 h postcooling. Experiment 3 determined if egg yolk or glycerol affected fertility. The seminal treatments were 1) NDSMG, 2) ndsmg+ey with previous removal of seminal plasma, and 3) NDSMG + GL. All samples were cooled to 5 °C and stored 24 h before insemination. Embryo recovery rates 7 d after ovulation were lower for mares inseminated with spermatozoa cooled in NDSMG + EY (17%, 424) or NDSMG + GL (13%, 324) extenders, than semen cooled in NDSMG (50%, 1224). We concluded that egg yolk (with seminal plasma removal) or glycerol added to NDSMG extender did not depress MOT or PMOT of cooled stallion spermatozoa but adversely affected fertility.

The primary factors affecting fertility in a program utilizing artificial insemination (A.I.) are number and quality of spermatozoa in the inseminate, timing and frequency of insemination, volume inseminated, seminal handling, seminal extenders, and cleanliness of procedures and equipment. The number of spermatozoa available for insemination depends upon age of the stallion, season of the year, testicular size, frequency of seminal collection and stallion sexual behavior. Other factors affecting fertility, in general, are inherent fertility of the animals, nutrition, disease, hormonal concentrations in the blood and overall management.

Seminal samples were collected at regular intervals, from 18 stallions from February 6 through July 5 to determine the relationship between morphologic and seminal characteristics of stallion spermatozoa. The highest correlation was between percentage of morphologic normal and progressively motile spermatozoa in extended and neat semen (r=0.63 and 0.61, respectively; P<0.001). Spermatozoal motility in extended and neat semen was negatively (P<0.001) correlated with spermatozoa with separated necks (r=0.40 and-0.41, respectively). A correlation of 0.47 (P<0.001) was also found between percentage of normal and total spermatozoa. Moderate correlations among other morphologic characteristics also were observed. For example, percentage of neck abnormalities was correlated (P<0.001) with mid-piece (r=0.47) and principal-piece (r=0.42) abnormalities. Similarly, mid-piece abnormalities were correlated (P<0.001) with principal-piece abnormalities (r=0.47). A correlation of 0.47 (P<0.001) existed between head-and mid-piece abnormalities.