Biomedical subjects

J J Dufour

Publications and source records attributed to J J Dufour.

At least 19 recordsLinked to original sources

PubMed2000

Effects of the Booroola Fec gene on ovarian follicular populations in superovulated Romanov ewes pretreated with a GnRH antagonist.

Endocrine control of follicular growth was studied in mature Romanov ewes carrying (RF+) or not carrying (R+2) the Booroola Fec gene during an oestrous cycle after gonadotrophin-dependent follicles were suppressed by treatment with an antagonist of GnRH (Antarelix, 0.5 mg per day) and superovulatory treatment was administered. The left ovary was removed after 10 days of treatment (saline or Antarelix) and the right ovary was removed at the end of the superovulatory treatment. Ewes of both genotypes treated with Antarelix had lower plasma LH concentrations than did controls from day 0 to day 10. The inhibitory effect of Antarelix on LH concentration increased with day of treatment. The variability in FSH concentrations during the initial 10 days was reduced by Antarelix treatment in both genotypes. Plasma FSH concentrations were higher in RF+ ewes than in R+2 ewes. In both genotypes, FSH concentrations varied significantly with day of treatment, with the lowest concentrations at day 8 and the highest concentrations at day 5. RF+ ewes had a greater total and atretic number of antral follicles 0.62-1.12, 1.12-2.00 and 2.00-3.00 mm in diameter (classes 2, 3 and 4) than did R+2 ewes before and after superovulatory treatment. After superovulatory treatment, the total number of atretic and non-atretic follicles > 3.00 mm in diameter (class 5) increased in both genotypes. Superovulatory treatment also increased the number of total and atretic class 4 follicles in RF+ only. Conversely, superovulatory treatment decreased the mean number of class 3 follicles in both genotypes, while the number of atretic follicles was decreased only in R+2 ewes. Antarelix treatment significantly reduced the percentage of follicles > 2.00 mm in diameter in RF+ but not in R+2 ewes. Antarelix treatment before superovulatory treatment increased the total number of class 4 follicles in both genotypes but the increase was more significant in RF+ than in R+2 ewes. These results indicate that Antarelix pretreatment favours a greater superovulatory response in Romanov ewes carrying the Fec gene because ovulatory follicles are recruited from a wider range of follicular size classes.

Animals↗

PubMed1999

Intracranial facial nerve reconstruction.

Surgery for tumours of the cerebellopontine angle (CPA) or the internal auditory canal (IAC) is sometimes complicated by the severing of the seventh nerve. Many procedures are available for facial reanimation. Among these, primary intracranial VII-VII reanastomosis is considered as the method of choice. This series reviews all the cases of primary intracranial facial nerve reconstruction that we have performed either directly or with the use of a nerve graft interposition. Functional results are analyzed according to the House-Brackmann grading scale. The advantages and benefits of this technique are discussed as compared with other methods of facial reanimation, namely, the hypoglossal-facial anastomosis.

Adult↗

PubMed1996

Effect of a single injection of a long-acting gonadotropin-releasing hormone agonist on prepubertal male and female pigs on reproductive organs, growth performance and sensory qualities of pork roasts.

Crossbred pigs (n = 200) were used to study the effects of a long-acting form of gonadotropin-releasing hormone (GnRH) agonist on the reproductive systems of male and female pigs and their growth performance and sensory quality of pork roast. Treatment was a single injection of a controlled release formulation of GnRH agonist [D-Trp6, des-Gly10]-GnRH ethylamide to release 5 micrograms/(kg x day) for 4 months beginning when the pigs were 66 +/- 2 days old. Pigs were allocated to five groups of 40 animals each: males castrated (CM) at 13 +/- 2 days, intact males (IM), treated males (TM), intact females (IF) and treated females (TF). Ovarian and uterine weights at slaughter averaged 3.67 and 79.8 g, respectively, in IF compared with 1.38 and 26.5 g in TF (P < 0.05). Testicular weights were 203 g in IM and 36.8 g in TM (P < 0.05). Microscopic observations of the testes revealed an absence of sperm cells but the presence of germ cells. Steroid concentrations at slaughter from all pigs showed that intact males had significantly more testosterone in their serum (26.36 +/- 9.87 nmol/L) compared with TM, CM, IF or TF groups and that treated males had intermediate concentrations (12.50 +/- 7.44 nmol/L) higher (P < 0.05) than those in CM and TF. Administration of GnRH agonist during the growth period of male pigs had no consistent effect on growth performance, but as compared to IM pigs, some of the carcass characteristics such as meat ratio (49.1 vs 50.2% in TM and IM; P < 0.001), dressing percentage (77.5 vs 76.5% in TM and IM; P < 0.05) and average backfat (20.8 vs 17.6 mm in TM and IM; P < 0.05) were modified by such a treatment. Meat quality, however, as determined by flavor and tenderness evaluations by sensory panelists, were similar (P < 0.05) in all groups and off-flavor scores were lower in TM than in IM (P < 0.001). As for males, backfat and meat ratio were different in TF compared to IF (P < 0.05) and roast juiciness was higher in TF than IF (P < 0.05). These results suggest that GnRH agonist can reduce gonadal secretory activity to castration levels during the growth period of prepubertal male pigs and could be an alternative to surgical castration in the pork industry with no negative effects on growth and meat quality. No advantage to endocrine castration in females was found.

Animals↗

PubMed1995

Development of a schwannoma within a facial nerve neurofibroma: a case report and literature review.

We report the presence of a schwannoma within a neurofibroma of the intratemporal facial nerve. This neurofibroma recurred 39 years after its first excision in the parotid gland. Although some believe that schwannomas and neurofibromas represent the same entity, these tumors present distinctive histopathologic and clinical characteristics, which are discussed. The extreme rarity of a schwannoma developing within a neurofibroma is underlined. This is the first report of such an association occurring within a cranial nerve.

Cranial Nerve Neoplasms↗

PubMed1995

Hormonal induction of ovulation stimulates atresia of antral follicles in gilts.

Two breeds of prepubertal gilts known to differ in their ovarian development were used to compare the effect of hormonally stimulated ovulation on follicle numbers and proportion of follicular atresia in size classes other than preovulatory follicles. Hormonal treatments (hCG or eCG-hCG) were given to Meishan gilts (n = 36) at 3, 2, and 1 standard deviations (SD) before the mean age of puberty (51, 64, and 77 days of age) and to Large White gilts (n = 24) at 3 and 1 SD before the mean age of puberty (140 and 166 days of age). Ovarian follicle populations determined in the right ovaries 18 h after hCG injection alone (hCG) or 72 h after eCG injection (eCG-hCG) were compared with those in the left ovaries, which had been removed prior to injections. Follicles with dispersed cumulus cells around the oocytes (expected ovulations) observed after hormonal treatments (right ovaries) were considered for follicular measures and categorized into specific size classes according to their diameter. Human CG alone did not affect any follicular parameters measured at any age in either of the two breeds studied. The overall population of nonatretic follicles was significantly reduced by the eCFG-hCG treatment in the Large White breed when imposed at either 3 or 1 SD before the mean age of puberty (262.6 vs. 158.8; p < 0.01). Among the various follicle size classes studied, eCG-hCG treatment significantly decreased the mean number of follicles in size classes 2 (1.13-2.00 mm in diameter) and 3 (2.01-3.56 mm in diameter) at either 3 or 1 SD before the mean age of puberty in the Large White gilts (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Synchronization of ovarian follicular waves with a gonadotropin-releasing hormone agonist to increase the precision of estrus in cattle: a review.

Treatment with GnRH and PGF2 alpha is a practical method for controlling ovarian follicular and luteal functions and increasing the precision of estrus synchronization in cyclic and acyclic postpartum cows and heifers. This method reduces considerably the period of time needed for estrus detection; it synchronizes the estrous cycle of 70 to 80% of the cyclic cows to within a 4-d interval without any detrimental effect on the fertility rate (65 to 85%). Moreover, resumption of ovarian activity and normal fertility in acyclic cows in favored. Administration of GnRH eliminates the large follicles by ovulation or atresia and induces emergence of a new follicular wave within 3 to 4 d after treatment at any stage of the estrous cycle, but it limits further growth of these emerging follicles by increasing atresia. The precision of estrus and the unaltered fertility rate is due to the synchronized selection of a new larger growing follicle, which becomes the ovulatory follicle after PGF(2 alpha)-induced luteolysis 6 d after GnRH treatment. Also, fixed-time AI programs without the need for estrus detection may be possible using a second injection of GnRH in a GnRH-PGF(2 alpha)-GnRH protocol to ovulate the selected follicle at a precise time. We describe a physiological model to explain how the precision of estrus is improved following PGF(2 alpha)-induced luteolysis, via the effect of pretreatment with GnRH on follicular development and luteal functions in cattle. Application of this model to the development of reliable methods of fixed-time insemination is also explored.

Animals↗

PubMed1995

Buserelin alters the development of the corpora lutea in cyclic and early postpartum cows.

Changes in proportions of luteal cells after buserelin treatment were studied in the corpus luteum (CL) that was present at the time of treatment (CLP) and in the buserelin-induced CL (CLI) of cyclic and acyclic postpartum cows. On d 0 of the experimental period, eight cyclic (Cyc-sal) cows were injected with saline, whereas eight cyclic (Cyc-bus) cows and eight acyclic (Acyc-bus) cows were treated i.m. with 8 micrograms of buserelin. On d 3 or 6, ovaries were collected and stained using histological techniques. As determined with the point-counting method, the number of nuclei in the CLP was similar on d 3 in Cyc-bus and Cyc-sal groups but was lower (treatment x day, P < .001) in the Cyc-bus group than in the Cyc-sal group on d 6. The volume of the CLP was similar on d 3 in the two groups but was greater (treatment x day, P < .04) in the Cyc-bus than in the Cyc-sal group on d 6. The number of nuclei in the CLI was greater (P < .001) in cyclic than in acyclic cows on d 3 and 6 after treatment. The volume of the CLI was lower (P < .001) in cyclic than in acyclic cows on d 3 and 6. Buserelin did not change the profile of progesterone in cyclic cows from d 0 to 6, but concentrations of progesterone increased (P < .01) in acyclic cows 3 to 6 d after buserelin treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Histological populations and atresia of ovarian follicles in postpartum cattle treated with an agonist of gonadotropin-releasing hormone.

Surface and histological changes of ovarian follicles and degree of atresia were characterized 3 and 6 d after a treatment with a GnRH agonist (buserelin) in postpartum beef cows. Sixteen cyclic cows on d 7 of their estrous cycle and eight acyclic cows were used. On d 0 of the experimental period, eight cyclic cows were injected with 2 mL of physiological saline and the remaining eight cyclic cows and the acyclic cows were injected i.m. with 8 micrograms of buserelin. Ovaries were collected 3 or 6 d later (n = 4 cows per group per day). All follicles (> 1.57 mm) were observed microscopically, measured using routine histological techniques, and classified as either nonatretic or atretic, with early or late atresia, and grouped into Class 1, 1.57 to 3.67 mm, Class 2, 3.68 to 8.56 mm, or Class 3, > 8.56 mm. Buserelin induced formation of new corpora lutea in all cows but one (acyclic cow). Class 1 follicles decreased on d 3 but increased on d 6 (day x treatment, P < .004), whereas those of Class 2 increased (P < .07) on both d 3 and 6 after buserelin treatment. However, within Class 2 follicles, we detected an increase on d 3 and 6 in the number (P < .01) and proportion (P < .07) of atretic follicles, an increase in the number of follicles in late atresia on d 6 (day x treatment, P < .03), and a decrease in the number (P < .06) and proportion (P < .03) of nonatretic follicles on d 6 (day x treatment).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Influence of corpus luteum and induced ovulation on ovarian follicular dynamics in postpartum cyclic cows treated with buserelin and cloprostenol.

The influence of the corpus luteum (CL) at the time of buserelin treatment and of buserelin-induced ovulation on the dynamics of ovarian follicular development was determined in 18 postpartum cyclic beef cows injected i.m. with 8 micrograms of buserelin on d 0 (d of treatment) and with 500 micrograms of cloprostenol (PGF) 6 d later. From d 0 to onset of estrus, ovaries were examined ultrasonographically, and blood samples were collected daily. Number of medium (5 to 10 mm) follicles and diameters of the two largest (F1 and F2) follicles in each cow were recorded. Cows were grouped according to the presence (CL+) or absence (CL-) of an active CL before buserelin injection and the presence (OV+) or absence (OV-) of a buserelin-induced ovulation (OV). Three groups were formed: CL-OV+ (n = 8), CL+OV+ (n = 6), and CL+OV- (n = 4). Buserelin induced an ovulation in all CL- cows (progesterone [P4] < .3 ng/mL) and in CL+ cows that had P4 < 4 ng/mL but did not in CL+ cows that had P4 > 8 ng/mL. Within CL+ cows, buserelin-induced ovulation (OV+) was associated with a smaller (P < .0001) increase in F1 and F1-F2 diameters and a transient increase in the number of medium follicles that was greater (P < .03) and of a longer duration (P < .01) than in OV- cows. After PGF, the increase in F1 and F1-F2 diameters was still greater in OV+ than in OV- cows (day x OV; P < .05). In all cows, the selection of the preovulatory follicle occurred before PGF injection. Results indicate that a buserelin-induced ovulation was dependent on P4 concentrations at the time of treatment. Subsequently, ovarian follicular dynamics were altered by a GnRH-induced ovulation, but emergence and selection of a large growing follicle occurred in all cows within 6 d of treatment. This follicle became the preovulatory follicle following PGF-induced luteolysis.

Animals↗

PubMed1994

Intratemporal vascular malformations (angiomas): particular clinical features.

Vascular malformations (angiomas) represent 1% of all pathologies of the temporal bone, including those of the cerebellopontine angle (CPA). We report six new cases of angiomas and compare them to the 48 cases listed in the literature published since 1949. Angiomas develop more frequently in the internal auditory canal (IAC) and at the geniculate ganglion (GG). When present in the IAC, rapidly progressive hearing loss is found in 88% of the patients reported in the literature and in 100% of patients in our series; facial nerve dysfunction is found in 72% and 60% of cases, respectively. The average tumour size is less than 10 mm. Acoustic neuroma, the most frequent tumour of this area, causes a slowly progressive sensorineural hearing loss in 75% of cases and facial weakness in 0.8%, according to the literature. Only 10% of acoustic neuromas measure less than 10 mm. Angiomas differ from acoustic neuromas in their rapid onset of sensorineural deafness and much greater incidence of facial nerve dysfunction despite a smaller tumour size.

Adult↗

PubMed1993

Comparative follicular development in Meishan and Large White gilts during prepubertal periods and its relation to hormonal stimulation.

Changes in follicular development in the left ovary and ovarian response to hormonal injections (hCG or eCG and hCG) in the right ovary were studied in Meishan gilts (n = 36) at 3, 2, and 1 standard deviations (SD) before the mean age of puberty (51, 64, and 77 days of age) and in Large White gilts (n = 24) at 3 and 1 SD (140 and 166 days of age). Left ovaries were removed at the time of hormonal treatments and the remaining ovaries were removed 18 h after hCG was injected alone (hCG) or 72 h after eCG was injected (eCG-hCG). Both nonatretic and atretic (> 4 pyknotic bodies) antral follicles > 0.6 mm in diameter were identified in the left ovaries by histological techniques. LH-sensitive follicles were identified in the right ovaries by counting follicles with dispersed cumulus cells around the oocytes. All large White gilts showed the presence of antral follicles at both 3 and 1 SD before puberty while 6, 7, and 12 Meishan gilts had antral follicles > 0.6 mm at 3, 2, and 1 SD before puberty, respectively. In Large White gilts, the mean number of nonatretic antral follicles > 0.6 mm remained constant at 3 and 1 SD before puberty, while in Meishan gilts, the mean number increased as gilts got older. Mean percentage of class 1 nonatretic follicles (0.6-1.12 mm) of the total number of nonatretic follicles increased significantly with age in Meishan gilts (p < 0.02), while those of class 3 (2.01-3.56 mm) decreased significantly (p < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗

PubMed1992

Influence of an agonist of gonadotropin-releasing hormone (buserelin) on estrus synchronization and fertility in beef cows.

The objective of this experiment was to determine the effect of sequential treatment with buserelin (a GnRH agonist) and cloprostenol (a prostaglandin F2 alpha analog) on estrous response and fertility in beef cattle with different ovarian conditions. On d 0 (1st d of treatment), the control group (n = 52, 10 heifers and 42 cows) and the GnRH group (n = 48, 10 heifers and 38 cows) received 2 mL of saline or 2 mL of Receptal (8 micrograms of buserelin), respectively. On d 6, all cows that had not exhibited spontaneous estrus were given i.m. 500 micrograms of cloprostenol (PGF). Ultrasonography on d 0 and assays of progesterone in blood on d -11, 0, and 6 were used to identify follicular and luteal status of animals. Cattle were observed for estrus from d 0 to 10. Cows showing estrus were bred artificially 12 h after onset of estrus. Over the 10-d period, the number of cows detected in estrus and pregnancy and conception rates were identical for the two groups. However, between d 0 and 6, the proportion of cows exhibiting estrus was lower (P less than .01) in the GnRH group than in the control group. Between d 6 and 10, the synchronization rate and precision of estrus were greater (P less than .01) in the buserelin-treated group than in the control group. Conception rate and interval from PGF injection to onset of estrus were not different between the two treatment groups. Presence of a large (greater than 10 mm) follicle on d 0 enhanced synchronization rate and precision of estrus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

Effects of pregnant mare's serum gonadotropin treatment on follicular populations and ovulation rates in prepuberal gilts with two morphologically different ovarian types.

Two experiments were conducted to determine the effects of pregnant mare's serum gonadotropin (PMSG) on follicular populations and ovulation rates in prepuberal gilts with grape-type (GT) and honeycomb-type (HT) ovaries. The follicular populations were determined at 170 d of age (d 0) and 19 d after PMSG (d 19). In Exp. 1, the mean number of macroscopic follicles of Classes 2 and 3 was greater (P less than .05) in GT (n = 11) than in HT (n = 32) ovaries at d 0, whereas the mean number of those of Class 1 was greater (P less than .05) in HT ovaries. At d 19, no difference was observed between the two ovarian types for any class of follicles. The PMSG-induced ovulation rates were comparable between the two ovarian types (8.3 vs 7.9, GT vs HT, respectively; P greater than .10). In Exp. 2, the microscopic follicular populations were determined on right and left ovaries removed, respectively, on d 0 and 19. At d 0, GT ovaries (n = 5) contained a greater number of Class 5 nonatretic (P less than .01) and atretic (P less than .02) follicles than did HT ovaries (n = 5), whereas at d 19 the mean number was not statistically different between the two ovarian types (P greater than .10). In contrast, gilts with HT ovaries contained a greater (P less than .01) number of Class 4 atretic follicles than gilts with GT ovaries at d 0, whereas at d 19 the mean number was not statistically different between the two ovarian types (P greater than .10).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

Ovarian morphological conditions and the effect of injection of human chorionic gonadotropin on ovulation rates in prepuberal gilts with two morphologically different ovarian types.

The purpose of this experiment was to determine the ovulation rate after treatment with human chorionic gonadotropin (hCG) in two groups of gilts characterized by different ovarian morphology: grape-type (GT; n = 11) and honeycomb-type (HT; n = 7). At 170 d of age (d 0), gilts were examined by laparoscopy and ovarian type was determined by the distribution of macroscopic follicles present on the ovarian surface. Five to ten minutes after surgery, each gilt received a single injection (i.m.) of 750 IU of hCG. At d 0, GT ovaries had a greater number of large follicles (greater than or equal to 6 mm) than HT ovaries (10.0 +/- .5 vs 2.6 +/- .3; P less than .05), whereas HT ovaries had more small follicles (1 to 3 mm; HT: 42.3 +/- .8 vs GT: 26.7 +/- .9; P less than .05) and total follicles (HT: 59.4 +/- 2.3 vs GT: 52.2 +/- 1.5; P less than .05), although numbers of medium follicles (4 to 5 mm) were similar (GT: 15.6 +/- .8 vs HT: 14.6 +/- 1.7; P greater than .10). Number of induced corpora lutea (CL) per ovary was greater (P less than .05) in gilts with GT ovaries (10.59 +/- 2.9 CL) than in gilts with HT ovaries (5.21 +/- .66 CL). Total weight of luteal tissue (LT) per ovary and serum progesterone concentrations 8 d after induction of ovulation were greater in GT gilts than in HT gilts (GT: 6.37 +/- 1.09 g vs HT: 3.31 +/- .49 g for LT, P less than .05; GT: 21.08 +/- 4.76 ng/ml vs HT: 13.40 +/- 2.05 ng/ml for progesterone, P less than .07).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Follicular dynamics and dominance in Booroola x Finnish Landrace and Booroola x Suffolk ewes heterozygous for the F gene.

To study the influence of the F gene on follicular dynamics and dominance, 2-year-old Booroola x Finnish Landrace (BFL, N = 17) and Booroola x Suffolk (BS, N = 18) ewes were compared with contemporary purebred Finn (FL, N = 18) and Suffolk (S, N = 18) ewes. In Exp. 1, oestrous cycles of ewes were synchronized during the breeding season with progestagen-impregnated sponges. At sponge removal (Day 0), 14 days after insertion, ewes of each of the 4 genetic groups were assigned to Group 1 in which all follicles visible on both ovaries were destroyed by electrocauterization except for the largest (F1) which was marked, Group 2 in which all visible follicles on both ovaries were destroyed, or Group 3 in which the 3 largest follicles of both ovaries were identified as F1, F2 and F3 and marked. At 48 h after treatment (Day 2), follicular growth was evaluated. At Day 0, the mean number of small follicles (1-3 mm) was higher (P less than 0.05) for BS, S and BFL (35.8, 35.1 and 32.9) than FL (24.9) ewes. Large follicles (greater than or equal to 4 mm) were more numerous (P less than 0.05) in FL (3.5) than in BS (2.1) ewes, BFL and S ewes being intermediate. Diameter of the F1 follicle was larger (P less than 0.05) for S (7.6 mm) than FL, BS and BFL (5.8, 5.1 and 5.1 mm) ewes. In Group 1, all F1 follicles marked at Day 0 ovulated at oestrus after sponge removal for BFL, BS and S ewes while in FL ewes, 2 of 6 F1 follicles regressed. In ewes ovulating, only the F1 follicle ovulated except for one S ewe which shed one more ovum. In Group 2, there were no follicles greater than or equal to 4 mm at Day 2 and no ewes ovulated after treatment. In Group 3, the proportion of marked follicles that ovulated was higher for S ewes than in those of the prolific genotypes. The number of follicles not marked at Day 0 but ovulating (compared to the total number of ovulations) was higher in BFL, BS and FL (8/11, 9/13 and 9/13) than S (3/10) ewes. In Exp. 2, prolific (BFL + BS) and non-prolific (S) ewes were compared following destruction of follicles greater than or equal to 3 mm with the F1 left intact (Treatment 1) or destroyed (Treatment 2), 12 days after sponge insertion.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1990

Influence of breed of fetus on periparturient endocrine responses and subsequent milk production of Ayrshire dams.

Purebred Ayrshire females were assigned to two groups based on the breed of fetus carried during gestation. In group 1, Limousin embryos were transferred nonsurgically into Ayrshire recipients (10 heifers and 1 cow), and in group 2, 11 Ayrshire heifers and 1 cow were inseminated artificially to Ayrshire bulls. Blood samples were collected daily from d 265 of gestation until d 15 postpartum from 5 heifers of each group. Milk yield was recorded on alternate weeks during the first 20 wk postpartum. Calf birth weight was higher (44.2 vs. 35.4 kg) and gestation was longer (297.4 vs. 280.2) in Ayrshire dams bearing Limousin fetuses than in those bearing Ayrshire fetuses. Daily milk production for the first 20 wk was lower (18.1 vs. 20.8 kg) in Ayrshire dams bearing Limousin fetuses than in those bearing Ayrshire fetuses. Prepartum decrease in progesterone concentrations and increase in estrone concentrations were faster in Ayrshire heifers bearing Limousin fetuses than in those bearing Ayrshire fetuses. Profiles of peripartum concentrations of bovine placental lactogen differed between Ayrshire carrying different families of Limousin fetuses but were similar in those carrying families of Ayrshire fetuses. The concentrations of 15-keto-13,14-dihydroprostaglandin F2 alpha were lower during the postpartum period in heifers than gave birth to Limousin calves than in those that had Ayrshire calves. In conclusion, the breed of fetus influences physiological and endocrine responses of the dam, which might have some effect on milk production of the dam.

Animals↗

PubMed1989

Survival rate and development of fetuses during the first 30 days of gestation after folic acid addition to a swine diet.

At weaning, 162 sows were assigned randomly to six treatments (27 in each treatment) according to a 2 X 3 factorial arrangement: two levels of supplementary folic acid (0 and 5 mg/kg of diet) and three treatments to stimulate ovulation (none, flushing and pregnant mare serum gonadotropin [PMSG] injection). All sows were mated twice within 7 d after weaning. Of the 162 animals originally selected, 123 sows were pregnant and used in this trial. The flushing treatment consisted of allowing sows ad libitum access to feed from the day after weaning through the 1st day of behavioral estrus, whereas control animals received 2.4 kg of feed daily. The hormonal treatment consisted of one i.m. injection of 1,250 IU of PMSG the day after weaning. The commercial-type diet used as the control was computed to contain .6 mg folates per kilogram. Folic acid supplementation elevated (P less than .001) serum folates between weaning and 30 d of gestation. Fetuses of sows fed the diet supplemented with folic acid had a higher (P less than .05) total protein concentration than fetuses of control sows, whereas RNA and DNA concentrations and protein:DNA ratio were not affected. The PMSG treatment elevated (P less than .05) ovulation rate, whereas the flushing or folic acid treatments had no effect on this trait. The addition of 5 mg/kg folic acid to the commercial-type diet improved (P less than .05) the survival rate of fetuses during early gestation and tended (P = .096) to increase the number of fetuses presumably living at 30 d of gestation when this treatment was associated with high ovulation rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

PubMed1988

Effects of litter size and light regimen imposed during lactation on ovarian follicular population at weaning in third-parity sows.

Sixteen third-parity sows maintained under two photoperiod treatments (16 h light: 8 h dark [16 h] or 4 h light: 20 h dark [4 h]) were assigned to be unilaterally ovariectomized (left ovary) at weaning on d 28 after farrowing a small litter (12 or fewer piglets; S) or a large litter (more than 12 piglets; L). Antral follicles were classified as atretic or nonatretic and divided into six size classes. The right ovary was obtained at slaughter, 16 d after estrus was detected. Number of antral follicles in the left ovary was greater (P less than .05) for L sows (540) than for S sows (427). Sows exposed to 16 h of light with large litters had a higher number of atretic follicles than all other groups (litter size x photoperiod interaction, P less than .05). Number of nonatretic follicles were similar between groups. However, when nonatretic follicles were classed by size (1 = smallest; 6 = largest), their distribution differed. In Class 1, L sows had more follicles than S sows (P less than .05). For Classes 3 and 4, photoperiod interacted with litter size to decrease the number of follicles in L 16 h sows (litter size x photoperiod interaction, P less than .05). These lower numbers of nonatretic follicles were related to a higher rate of follicular atresia in L 16 h sows. In Classes 2, 3 and 4, L 16 h sows had more atretic follicles than any other group (litter size x photoperiod interaction, P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗