Motility Characteristics and Fertilizing Capacity of Boar Spermatozoa Stained with Hoechst 33342

Flow cytometry sorting of spermatozoa using fluorescence dye Hoechst 33342 is the only effective sex selection methodology validated in numerous laboratories. This study was carried out to determine the effect of Hoechst 33342 on the motility and fertility of stained boar spermatozoa. Experiment 1 evaluated motility parameters (percentage of motile spermatozoa, velocity, angularity and oscillation) of boar spermatozoa stained with Hoechst 33342 by a computer‐aided sperm analysis (CASA) instrument. Spermatozoa (30 million/ml) were divided into five treatment groups and stained during 1 h at 35°C with 9, 18, 27, 60 and 90 μM of H33342. There were no differences in sperm motility patterns nor percentages of motile spermatozoa incubated in the presence of 9, 18 or 27 μM. Percentage of motile spermatozoa and motility parameters decreased significantly (p < 0.05) at 60 μM of Hoechst 33342. Spermatozoa were immotile at concentration of 90 μM. In experiment 2, pregnancy rates, farrowing rates and litter size from sows (n = 275) artificially inseminated (AI) with either Hoechst 33342 stained (27 μM) or unstained (control) spermatozoa were determined. Sows inseminated with stained spermatozoa had no significant lower pregnancy rate (88.33%) as compared with controls (90.32%). Staining neither affected farrowing rates (85.0 vs 87.7%) nor total number of piglets born (10.56 ± 0.32 vs 10.47 ± 0.24, stained and controls, respectively). No phenotypical abnormalities were registered among the newborn piglets. The data suggest that incubating spermatozoa with Hoechst 33342 at levels required for X‐ and Y‐bearing chromosome sperm sorting, does not impair sperm viability or their fertility after AI.     

The Effect of Two Antibiotic Mixtures on Haemophilus somnus, Campylobacter fetus ssp. venerealis, Mycoplasma bovis, and Ureaplasma diversum in Frozen Bovine Semen

A two-step semen-extending protocol was compared to a one-step protocol in its efficiency in inhibiting growth of Haemophilus somnus, Campylobacter fetus ssp. venerealis, Mycoplasma bovis , and Ureaplasma diversum in experimentally infected semen. In both protocols, the effect of an antibiotic mixture of 500 μg gentamycin, 100 μg tylosin, 300 μg lincomycin, and 600 μg spectinomycin (GTLS) was compared to a mixture of 500 IU penicillin, 500 IU streptomycin, 150 μg lincomycin, and 300 μg spectinomycin (PSLS). The one-step extending method was as effective as the two-step extending method. Both antibiotic mixtures were equally effective in controlling C. fetus . For H. somnus and U. diversum , the PSLS mixture was more effective than the GTLS mixture. It was striking that both antibiotic mixtures had no effect in decreasing the numbers of M. bovis .     

Muscle strain injuries of the hindlimb in eight horses: diagnostic imaging,management and outcomes

Objective To describe the clinical presentation, ultrasound findings, management and outcome in horses with muscle tear injuries of the hindlimbs. Design Retrospective case series Procedure Medical records of eight horses were reviewed and information on signalment, history, presenting complaint, physical examination findings and further diagnostic tests were recorded. Diagnosis of muscle injury was determined by the presence of abnormal ultrasound findings, compared with the contralateral limb, and, when required, nuclear scintigraphy. Follow-up information was obtained via telephone interviews with owners, trainers and referring veterinarians. Results Muscle tears causing lameness were identified in the middle gluteal (3), semitendinosus (1), semimembranosus (2) and gracilis (2) muscles. Tears were classified by ultrasound imaging as partial (6) or complete (2). The degree of lameness did not appear to be indicative of the extent of injury or of completion of healing. Long-term follow-up was available for seven horses and the outcome was favourable in six cases. Conclusions and clinical relevance Ultrasonography is useful in the diagnosis and assessment of moderate to severe muscle strain injuries. The prognosis appears to be favourable in most cases, although recurrence of injury and lameness can delay the return to athletic activity and an inferior outcome with persistent gait abnormality may occur.     

Effect of Oxytocin Treatment on Artificial Insemination with Frozen–Thawed Semen in Murciano–Granadina Goats

The site where the semen is deposited appears to be one of the most important factors affecting pregnancy of inseminated goats. In Murciano–Granadina (MG) goats, post-cervical insemination is achieved in a limited number of females. An effective way to increase fertility rate could be by increasing post-cervical inseminations. Effect of exogenous oxytocin application to facilitate the cervical penetration and its effect on kidding rate and prolificacy in MG goats were investigated. Oestrus was synchronized using progesterone-impregnated sponges for 11 days. Females were randomly divided into three groups (n = 190) and received either an i.v. injection of 100 or 200 IU of oxytocin or saline solution 15 min before being inseminated. Data on semen deposition depth were recorded for each animal using a catheter scaled in centimetres (up to 4 cm). Depth of semen deposition was affected by the oxytocin treatment (p < 0.05). Oxytocin enhanced cervical passage only with the dose of 200 IU compared with the control group, increasing the deposition depth (2.9 cm vs 1.9 cm). No significant effect of oxytocin treatment on kidding rate and prolificacy was detected. Depth of semen deposition affected kidding rate (p < 0.01). In conclusion, oxytocin treatment improved the depth of semen deposition in AI of MG goats, but kidding rate and prolificacy was not affected. More studies must be conducted to assess the minimal effective dose required for sufficient cervical dilation, and to determine the effects of such doses of oxytocin on uterine motility, sperm transport and fertility in goats.     

In Vitro assessment of the nutritive value of expanded soybean meal for dairy cattle

ABSTRACT: Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent-extracted soybean meal (n = 5) were obtained from People's Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.     

In Vitro assessment of the nutritive value of expanded soybean meal for dairy cattle

Little information is available about the nutritive value of expanded soybean meal, which is produced by expansion of soybeans prior to solvent extraction of the oil. During processing, expanded soybean meal is subjected to additional heat, which might increase the concentration of ruminally undegraded protein. Processing of soybeans with heat during oil extraction could affect lysine availability by increasing ruminally undegraded protein or by impairing intestinal digestion. Our objective was to compare solvent and expanded soybeans with regard to chemical composition and nutritive value for dairy cattle. Samples of expanded soybean meal (n = 14) and solvent- extracted soybean meal (n = 5) were obtained from People’s Republic of China to study effects of the expansion process on nutritive value for dairy cattle. Solvent-extracted soybean meal (n = 2) and mechanically extracted (heated) soybean meal (n = 2) from the United States served as references for comparison. Samples were analyzed for crude fat, long-chain fatty acids, crude protein, amino acids, chemically available lysine, in situ ruminal protein degradation, and in vitro intestinal digestibility. No differences were found between solvent-extracted soybean meals from China and expanded soybean meals from China for crude fat, crude protein, amino acids, or chemically available lysine. In situ disappearance of nitrogen, ruminally undegraded protein content, and in vitro intestinal digestion of the ruminally undegraded protein were generally similar between solvent-extracted soybean meals made in China and expanded soybean meals made in China; variation among soybean meals was small. Results indicate that the additional heat from the expansion process was not great enough to affect the nutritive value of soybean meal protein for ruminants. Although expansion may improve the oil extraction process, the impact on the resulting soybean meal is minimal and does not require consideration when formulating ruminant diets.     

In vitro Maturation of Oocytes from Santa Ines Ewes Subjected to Consecutive Sessions of Follicular Aspiration by Laparoscopy

The success of embryo production in vitro depends upon the use of an efficient oocyte retrieval technique, and the best results have been obtained by laparoscopic aspiration. The aim of this study was to evaluate the effect of consecutive sessions of follicular aspiration on the quantity, quality and in vitro maturation competence of oocytes obtained from ewes subjected to hormonal stimulation. Six Santa Ines ewes underwent nine sessions of follicular aspiration by laparoscopy with a 7‐day interval between sessions, totalling 56 aspirations. After 24 h of culture, oocytes were stained and classified according to the stage of nuclear and cytoplasmic maturation. Oocyte retrieval rate was 61.4 ± 2%, resulting in a total of 249 oocytes. No significant variation was observed between sessions (p > 0.05). The average number of oocytes retrieved from each ewe was 6.4 ± 2 per session and 42 ± 4 in total. No significant difference was observed between the frequencies of the different stages of nuclear maturation: 32.72% mature, 40.74% immature and 26.54% degenerated/indeterminate oocytes; however, a significant difference was observed between the frequencies of the different stages of cytoplasmic maturation: 10.7% mature, 73.25% immature and 16.05% degenerated/indeterminate oocytes. No significant difference was observed in nuclear or cytoplasmic maturation between the weeks of procedure. We conclude that after nine consecutive sessions of follicular aspiration, the quantity and quality of retrieved oocytes remained unchanged as well as the levels of nuclear and cytoplasmic maturation obtained, demonstrating the viability of this technique for repetitive follicular aspirations on the same donor.     

Endometrial Explant Culture to Study the Response of Equine Endometrium to Insemination

Mating‐induced endometritis (MIE) is ubiquitous in the horse after natural mating and artificial insemination with frozen/thawed semen causing the most aggressive response. The majority of mares eliminate MIE 24–48 h after insemination. An endometrial explant culture was tested as a potential in vitro exemplar for sperm‐induced MIE. Endometrial prostaglandin F_2α (PGF_2α) secretion and expression of interleukin‐8 (IL‐8) were used as markers of inflammation. Endometrial explants were cultured from uteri collected from follicular phase mares. Explants were challenged with 1 or 10 × 10⁶ sperm/ml frozen/thawed semen, chilled semen, washed sperm or seminal plasma. Medium was collected 24 and 72 h after challenge and assayed for PGF_2α by radioimmunoassay. Treatment of endometrial explants with frozen/thawed, chilled semen or washed sperm did not change the secretion of PGF_2α compared with untreated controls. However, 24 h after challenge cultured explants expressed IL‐8. The in vitro endometrial explant system did not represent the in vivo response to semen when PGF_2α was used as a marker of inflammation, yet the use of gene expression as an inflammatory marker warrants further investigation.     

Factors Affecting Pregnancy Rate in Artificial Insemination with Frozen Semen During Non-Breeding Season in Murciano–Granadina Goats: a Field Assay

An artificial insemination programme was carried out to study the effect of factors such as depth of semen deposition, inseminator skill, farm, sire and expression of oestrus on pregnancy rate in Murciano-Granadina (MG) goats during non-breeding season and using frozen semen. Frozen-thawed semen from six males was applied by three technicians to inseminate a total of 551 goats in 17 farms distributed throughout the Mediterranean area of Spain. Pregnancy rate was determined at 6 weeks after insemination by transabdominal ecography. Overall pregnancy rate was 57%. Farm and depth of semen deposition affected pregnancy rate, whereas the sire and the technician had no effect. The deeper the semen was deposited in the genital tract, the higher was the rate of pregnancy obtained, being greater when the catheter reached the uterus. In spite of the relevant difference observed (48.2% vs 59.0%), pregnancy rate of females not coming into oestrus until 30 h after sponge removal was not significantly different, compared with those showing oestrus during the OD procedure. In conclusion, our field assay data on AI in MG goat with frozen-thawed semen showed that post-cervical insemination presented significantly greater pregnancy rate in comparison to when semen is deposited in the vagina or in the caudal part of the cervix.