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.     

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.     

Osteopetrosis in a neonatal donkey

Osteopetrosis is a rare disorder characterised by a defect in osteoclastic bone resorption. This report describes osteopetrosis in a neonatal donkey that suffered a displaced tibial fracture. Radiographic examination identified generalised reduction in medullary cavity size, thickened mid‐diaphyseal cortices and conical metaphyseal bone extending toward the mid‐diaphysis of long bones. Postmortem examination identified additional fractures and brittle bones. Histologically, osteoclasts were absent in multiple bone sections. Diaphyseal cortices consisted of concentric bone lamellae with marrow tissue infiltration. Large wedges of secondary spongiosa extended from the metaphyseal growth plate. Clinical and histopathological features were similar to an osteoclast‐deficient, autosomal recessive form of osteopetrosis in humans.     

Realized reproductive success of polygynous red-winged blackbirds revealed by DNA markers

Hypervariable genetic markers, including a novel locus-specific marker detected by a mouse major histocompatibility complex probe, reveal that multiple paternity is common in families of polygynous red-winged blackbirds (Agelaius phoeniceus). Almost half of all nests contained at least one chick resulting from an extra-pair fertilization, usually by a neighboring male. Genetically based measures of reproductive success show that individual males realize more than 20% of their overall success from extra-pair fertilizations, on average, and that this form of mating behavior confounds traditional measures of male success. The importance of alternative reproductive tactics in a polygynous bird is quantified, and the results challenge previous explanations for the evolution of avian polygny.     

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.     

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.