In this study concentration and composition of non-esterified fatty acids (NEFA) in follicular fluid (FF) of high-yielding dairy cows were determined during the period of negative energy balance (NEB) early post partum. NEFA were then added during in vitro maturation at concentrations measured previously in FF to evaluate their effect on the oocyte's developmental competence. At 16 and 44 days post partum, FF of the dominant follicle and blood were collected from nine high-yielding dairy cows. Samples were analysed for NEFA concentration and composition. NEFA concentrations in FF (0.2-0.6 mmol/l) during NEB remained +/- 40% lower compared with serum (0.4-1.2 mmol/l). The NEFA composition differed significantly between serum and FF with oleic acid (OA), palmitic acid (PA) and stearic acid (SA) being the predominant fatty acids in FF. Based on these results, 5115 oocytes were matured for 24 h in serum-free media with or without (negative control) the addition of 0.200 mmol/l OA, 0.133 mmol/l PA or 0.067 mmol/l SA dissolved in ethanol or ethanol alone (positive control). Matured oocytes were fertilized and cultured for 7 days in SOF medium. Addition of PA or SA during oocyte maturation had negative effects on maturation, fertilization and cleavage rate and blastocyst yield. More (late) apoptotic cumulus cells were observed in cumulus-oocyte complexes matured in the presence of SA or PA. Ethanol or OA had no effect. These in vitro results suggest that NEB may hamper fertility of high-yielding dairy cows through increased NEFA concentrations in FF affecting oocyte quality.

/pdf/non-esterified-fatty-acids-in-follicular-fluid-of-dairy-cows-45g953u3bt.pdf

Non-esterified fatty acids in follicular fluid of dairy cows and their effect on developmental capacity of bovine oocytes in vitro.

Intrauterine position effects.

Recent Developments in the Roles of Vitamins and Minerals in Reproduction

Metabolic changes in follicular fluid of the dominant follicle in high-yielding dairy cows early post partum

Metabolite and ionic composition of follicular fluid from different-sized follicles and their relationship to serum concentrations in dairy cows.

To investigate some biochemical changes during bovine follicle development, ovaries were obtained from cyclic heifers (7 to 11 heifers/d on each day of the 21-d estrous cycle; N = 152). Follicular fluid from the two largest follicles from both ovaries and a pool from small follicles (N = 30/cow) were collected from each animal and analyzed for ionic, enzymatic and endocrine changes in relation to day of the estrous cycle, follicle size, rank and atretic or growing status. Follicular fluid alkaline phosphatase activity and ascorbate concentrations were highest in all follicular sizes during the earlier portion of the estrous cycle (d 1 to 12; P less than .05), then decreased to the lowest levels (d 13 to 21). As follicular size (diameter) increased lactate dehydrogenase (LDH), acid and alkaline phosphatase activity was reduced in follicular fluid (P less than .05). Alkaline phosphatase and LDH activity tended to be increased in atretic follicles (P less than .10), and was correlated with increased progesterone and androgen concentrations of follicular fluid (r = .4, P less than .05). Both albumin and total protein concentrations decreased as follicular diameter increased (P less than .05). Sodium concentrations in follicular fluid were greater in growing-antral than atretic follicles, and increased with follicular enlargement (P less than .05). Follicular potassium concentrations increased as the estrous cycle progressed (P less than .05), and tended to be elevated in atretic follicles (nonsignificant). Both Ca and Mg concentrations increased with follicular enlargement (P less than .05). Dehydroepiandrosterone and testosterone were the predominant androgens in follicular fluid (androstenedione, the lowest concentration); their concentration decreased with follicle development (P less than .05), but were quite variable. Estradiol was increased in growing follicles (P less than .01). Estrone and estradiol concentrations increased as ovulation approached, particularly in small follicles (less than or equal to 4 mm diameter). Changes of biochemical components found in follicular fluid that relate to the growth and atresia process may provide a more sensitive and accurate method to classify follicle status, and thus aid in understanding the complexity of events associated with maturation of the bovine follicle and oocyte.

Biochemical analysis of bovine follicular fluid: albumin, total protein, lysosomal enzymes, ions, steroids and ascorbic acid content in relation to follicular size, rank, atresia classification and day of estrous cycle.

Fetal intrauterine position relative to the sex of adjacent fetuses has an effect on reproductive performance in rodents. An experiment was conducted to determine whether sex of adjacent fetuses in utero has an influence on fetal and placental weights and whether the hormonal mechanisms documented in rodents are similar in fetal pigs. Sows were slaughtered at 70.1 +/- 1.7 d (n = 123) and 104.5 +/- .05 d (n = 135) of gestation. The fetuses and placentas were removed from the uterus and the position and sex of each fetus was recorded to indicate whether the fetus was between two males, two females, or a male and a female. Fetal blood was sampled for later hormonal analysis. At 70 d of gestation, male fetal and placental weights were heavier than those of females (P less than .05), but no differences were detected relative to the sex of adjacent fetuses. At 104 d of gestation, a fetus surrounded on each side in utero by fetuses of the opposite sex (two males or two females) was lighter in weight than a fetus surrounded by fetuses of the same sex (P less than .01). Differences in fetal weight due to the sex of adjacent fetuses were not related to placental function because placental weights were generally not different at 104 d of gestation. By 104 d of gestation, most placentas were not separated by necrotic regions and were in close apposition with surrounding placentas. No differences in growth or development could be related to hormonal effects (testosterone, estrone, or estrone sulfate) from surrounding fetuses.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship of fetal position within the uterus to fetal weight, placental weight, testosterone, estrogens, and thymosin beta 4 concentrations at 70 and 104 days of gestation in swine.

Three generations of selection for 56-d blood cholesterol concentrations were used to establish low and high cholesterol lines of pigs in which cholesterol concentrations differed by 39% in the last generation. Litter size (number of fully formed pigs born per litter) diverged with each successive generation of selection and, at the third generation, litter size differed between the low and high line by two pigs (high line = 8.5 +/- .6; low line = 10.5 +/- .5; P < .05). A random selection of offspring (gilts, n = 109; boars, n = 46; barrows, n = 94) from the third generation and a control line maintained throughout the experiment were monitored for hormonal and anatomical relationships that might provide insight into the mechanisms that altered fecundity. Ovulation rate (number of corpora lutea) as determined on d 60 of pregnancy was increased in the low (n = 29) compared with the high cholesterol line (n = 38; 11.8 +/- .3 vs 9.8 +/- .3, respectively; P < .05), and litter size continued to be increased in the low cholesterol line (P < .05). No differences were noted between lines in kidney, ovarian, or total corpora lutea weight. Empty uterine weight and adrenal weight were increased in the high cholesterol line (P < .05) in randomly selected offspring of the third generation, and liver weight increased in the low line (P < .05). Associated with increased concentrations of cholesterol were increased serum concentrations of progesterone (gilts) and testosterone (boars) in the high cholesterol line (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Reproductive, endocrine, and organ weight differences of swine selected for high or low serum cholesterol

Experiment 1 involved genetically lean and obese gilts and barrows injected for 42 d with 0, 2, or 4 mg/d of porcine somatotropin (pST; n = 96) Blood was collected at 0, 6, and 24 h after the initial pST injection and thereafter every 2 wk Experiment 2 involved lean and obese gilts and barrows (n = 48) that were administered implants that released 0, 2, or 4 mg/d of pST for 42 d Blood was collected at d 0, 7, 14, 28, and 42 of the study Thymic weights and a final blood sample were collected at the end of the 42-d trial Thymic weights increased (P < 01) with dose of pST in injected and implanted animals Thymosin beta 4 increased (P < 05) in a pST dose-dependent manner in injected and implanted animals, but concentrations were increased more in implanted animals Concentrations of thymosin beta 4 decreased or reached a plateau in gilts but continued to increase in barrows to the end of the trial Thymosin alpha 1 concentrations were increased (P < 01) in barrows compared with gilts, but the concentrations were not related to dose of pST Concentrations of pST in injected animals increased (P < 01) within 6 h after injection and had returned to basal concentrations by 24 h after injection Concentrations of pST in implanted animals were dose-dependent (P < 05) and remained increased throughout the trial Concentrations of IGF-I and -II were pST-dependent (P < 01) and increased throughout the trial period Outside of the pST dose relationships, temporal changes in thymosin beta 4 were not highly related to changes in pST, IGF-I, or IGF-II The pST dose-related increases in thymic weights and thymosin beta 4 concentrations are consistent with pST stimulation of the immune function in conjunction with overall increases of growth and efficiency of live weight gain in swine

T. Wise

Papers

Biochemical analysis of bovine follicular fluid: albumin, total protein, lysosomal enzymes, ions, steroids and ascorbic acid content in relation to follicular size, rank, atresia classification and day of estrous cycle.

Relationship of fetal position within the uterus to fetal weight, placental weight, testosterone, estrogens, and thymosin beta 4 concentrations at 70 and 104 days of gestation in swine.

Reproductive, endocrine, and organ weight differences of swine selected for high or low serum cholesterol

Porcine somatotropic regulation of thymic weight, thymosin beta 4, and insulin-like growth factors in lean and obese swine.