Serum biochemical parameters and embryo production during superovulatory treatment in dairy cattle

Liu

et al. 2010

J Assist Reprod Genet

Section: Discussionmentioning

confidence: 99%

Association of creatin kinase B and peroxiredoxin 2 expression with age and embryo quality in cumulus cells

Liu

et al. 2010

J Assist Reprod Genet

Reproduction in Domestic Animals

“…Although early follicle and oocyte development are not well-studied in ruminants compared with rodents, the regulation of early preantral follicle development in bovine is known to involve many hormones, such as oestradiol, testosterone, insulin, follicle stimulating hormone (FSH), vascular endothelial growth factor (VEGF), insulin-like growth factor 1 (IGF-1) and their binding proteins (Fortune 2003;Gigli et al 2006;Fortune 2006, 2007;Thomas et al 2007). Antral follicle and oocyte development as well as oocyte quality are also affected by gonadotropins and IGFs (Webb et al 2007) and metabolites such as glucose and blood urea nitrogen (BUN), non-esterified fatty acids (NEFA), magnesium (Mg), K and creatinine (Plym Forshell et al 1991;Iwata et al 2006;Chorfi et al 2007). These findings indicate that the physical condition of the animals profoundly affects folliculogenesis and oocyte quality.…”

Section: Introductionmentioning

confidence: 99%

Follicle Growth and Oocyte Developmental Competence in Cows With Liver Damage

Iwata

Tanaka

Kanke

et al. 2010

Follicle growth, oocyte quality or oocyte growing environment (follicular fluid) were evaluated in cows with severe liver damage (haemorrhage, telangiectasis, cholangitis and abscess) that were visually diagnosed at the slaughterhouse. Holstein cows aged 40-90 months with either a healthy liver (HL cow) or damaged liver (DL cow) were selected as donors. Follicle development kinetics was evaluated by counting the follicles at various developmental stages. In addition, the biochemical characteristics of the follicular fluids, developmental competence of preantral follicles cultured for 16 days in vitro and the ability of oocytes to develop to the blastocyst stage 8 days after fertilization were examined. DL cows had fewer secondary follicles than HL cows, and the correlation between the number of secondary follicles and the number of primary follicles differed among DL and HL cows. The follicular fluid of DL cows contained significantly lower levels of albumin and a higher total protein content than that of HL cows. Oocyte nuclear maturation assessed at 5, 16 and 21 h after beginning of culture was slower in DL cows than in HL cows, although the final maturation rates did not differ. The rate of polyspermic fertilization was significantly higher and the proportion of cleavage at 48 h after insemination and blastulation lower in DL cows compared with HL cows. When preantral follicles were cultured in vitro, the rate of follicles with normal morphology was lower in DL cows than in HL cows. These findings suggest that the kinetics of folliculogenesis differ among DL and HL cows and the developmental ability of preantral follicles and oocytes is lower in DL cows than in HL cows.

“…Lucy et al (1992) also found that the number and the size of follicles were higher in cows with higher blood cholesterol levels. In contrast, Chorfi et al (2007) observed that serum cholesterol levels in superovulated cows did not signif icantly influence the number of transferable embryos.…”

Section: Resultsmentioning

confidence: 79%

“…Several studies have also demonstrated a relationship between metabolic disorders and reproductive efficiency and, subsequently, embryo production (Chorfi et al, 2007;Ramos et al, 2007;Pfeifer et al, 2009).…”

mentioning

confidence: 99%

Use of endometrial cytology and metabolic profiles for selection of embryo donor cows

Sánchez¹,

López

Arias

et al. 2014

Span. j. agric. res.

The aim of this study was to evaluate the use of endometrial cytology and metabolic profiles for selection of donor cows in embryo transfer programmes. For this purpose, 69 clinically healthy Holstein cows were enrolled in the study. At the start of the superovulation procedure (Day 0), blood and endometrial samples were obtained to determine metabolic and uterine status, respectively. The cows were then subjected to porcine follicle stimulating hormone (pFSH) superovulation treatment, and embryos were recovered after 7 days. The mean number of embryos obtained per flush was 9.89±8.21 (4.63±5.34 viable embryos, 0.82±2.01 degenerated embryos and 4.57±6.44 unfertilized ova). The following statistically significant variables were entered in a regression model: beta-hydroxybutyrate, serum cholesterol, body condition, number of calvings and percentage of neutrophils. In almost all cases, the model explained some percentage of the variance: total number of embryos, 4.8% (p<0.05); number of degenerate embryos, 4.2% (p=0.051); and number of unfertilized ova, 14.2% (p<0.01). Statistical models for the percentage of viable embryos and unfertilized ova accounted for 24.0% and 29.4% of the variance, respectively, and both were statistically significant (p<0.01). The model for the percentage of degenerated embryos was statistically significant (p<0.05) and explained 4.4% of the variance. In conclusion, we have demonstrated that positive energy balance and healthy uterus can improve ovarian response and the proportion of viable embryos in cows. Efficient tools for monitoring the metabolic and uterine status should therefore be used in bovine embryo transfer programmes.