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1.
J Dairy Sci ; 104(11): 12127-12138, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34419270

RESUMO

Long-day photoperiod is known to positively affect milk production in confinement dairy systems, and it has been hypothesized that pineal melatonin (MT) secretion plays a substantial role in this process. Specialized mammalian photoreceptors that regulate MT secretion are optimally stimulated by short wavelength blue light. We investigated the blue light intensity administered to one eye required to suppress MT secretion in nonlactating dairy cows, and subsequently examined effects on milk production in grazing dairy cows. Following a 14-d light-dark 8:16 h environmental conditioning period, 5 nonlactating Holstein-Friesian cows were exposed to treatments of <1, 70, 125, 175, and 225 lx for 8 additional hours using a 5 × 5 Latin square design. Light was administered via headpieces fitted with light-emitting diodes emitting blue light (465 nm) to the right eye. All cows were then exposed to a light-dark 16:8 h cycle for one night via the indoor lighting system (>200 lx white light). Plasma samples collected at regular intervals were assayed for MT. A dose-dependent effect of light treatment on mean circulating MT concentrations (and 95% CI) was observed [9.4 (7.2, 12.3), 5.0 (3.8, 6.6), 4.4 (3.3, 5.7), 3.3 (2.5, 4.3) and 1.7 (1.3, 2.3) pg/mL for treatments of 0, 70, 125, 175, and 225 lx, respectively. Only the 225 lx treatment acutely suppressed plasma melatonin concentration to levels similar to the light-dark 16:8 h treatment [1.9 (1.4, 2.5) pg/mL]. Forty spring-calving cows were blocked on parity, calving date and Economic Breeding Index for milk production and assigned to the control treatment or blue light to a single eye (LT) treatment from calving through 32 wk of lactation. The cows assigned to LT treatment were fitted with headpieces providing 225 lx of blue light to the right eye from 1700 until 0000 h. Mean milk production (and 95% CI) during 32 wk of lactation was not affected by treatment [20.3 (19.3, 21.3) vs. 20.9 (19.8, 22.0) kg/d, control and LT, respectively]. Within multiparous cows, a treatment by week interaction was detected, whereby LT treatment increased milk production during the first 12 wk of lactation [25.8 (24.3, 27.3) vs. 28.0 (26.5, 29.5) kg/d; +8.5%], but had no effect thereafter. Treatment did not affect plasma insulin-like growth factor 1. We identified the blue light intensity to one eye required to acutely suppress MT concentrations. Transient favorable effects on milk production were observed in multiparous cows. It remains unclear how single-eye blue light treatment affects galactopoiesis in grazing dairy cows, and further research is needed to explore whether this modality of light delivery represents a useful means to aid productivity in pasture-based dairy systems.


Assuntos
Melatonina , Leite , Animais , Bovinos , Dieta , Feminino , Lactação , Paridade , Fotoperíodo , Gravidez
2.
Epilepsia ; 62(9): 2171-2179, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34289107

RESUMO

OBJECTIVE: This study aimed to compare rates of breastfeeding initiation and maintenance in women with epilepsy (WWE) with those of the general population and to identify factors affecting breastfeeding patterns in WWE. METHODS: We retrospectively reviewed data for the following variables in pregnant WWE (n = 102) and healthy women without epilepsy (n = 112): demographic characteristics (age, race, ethnicity), epilepsy type (focal or generalized onset), antiseizure medication(s), psychiatric comorbidities, postpartum seizure control, breastfeeding counseling, and lactation consultation. Fisher exact test and logistic regression analyses were performed to compare the rates of breastfeeding initiation and continuation in pregnant WWE with those of healthy pregnant women and to determine factors associated with rates of breastfeeding initiation and maintenance. RESULTS: The rate of breastfeeding initiation in WWE was significantly lower than in healthy women without epilepsy (50.9% vs. 87.6%), and WWE were less likely to maintain breastfeeding at 6 weeks (38.2%) and 3 months (36%) postpartum. Nearly half (53%) of WWE received antepartum breastfeeding counseling by their neurologists, and these women had higher odds of breastfeeding initiation and continuation (odds ratio [OR] = 2.53, 95% confidence interval [CI] = 1.14-5.72, p = .02). Postpartum consultation with a board-certified lactation consultant was associated with higher odds of breastfeeding continuation at 6 weeks (OR = 5.43, 95% CI = 1.39-27.23, p = .02) and at 3 months (OR = 4.9, 95% CI = 1.34-20.87, p = .019). Women taking levetiracetam were more likely to initiate and continue breastfeeding than those taking lamotrigine (OR = 6.22, 95% CI = 2.15-20.20, p = .001). SIGNIFICANCE: The initiation rate and duration of breastfeeding were significantly lower in WWE than in healthy women without epilepsy and were significantly associated with several factors. Identification of potential barriers to breastfeeding in WWE may lead to development of intervention strategies that can improve breastfeeding rates in WWE to maximize positive health outcomes for WWE and their infants.


Assuntos
Aleitamento Materno , Epilepsia , Anticonvulsivantes/uso terapêutico , Aconselhamento , Epilepsia/tratamento farmacológico , Epilepsia/epidemiologia , Feminino , Humanos , Gravidez , Estudos Retrospectivos
3.
J Dairy Sci ; 101(11): 10526-10535, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30146283

RESUMO

The aim of this study was to investigate the effect of progesterone (P4)-based timed artificial insemination (TAI) programs on fertility in seasonal-calving, pasture-based dairy herds. A total of 1,421 lactating dairy cows on 4 spring-calving farms were stratified based on days in milk (DIM) and parity and randomly allocated to 1 of 3 treatments: (1) control: no hormonal treatment; cows inseminated at detected estrus; (2) P4-Ovsynch: cows received a 7-d P4-releasing intravaginal device (PRID Delta; CEVA Santé Animale, Libourne, France) with 100 µg of a gonadotropin-releasing hormone (GnRH) analog (Ovarelin; CEVA Santé Animale) at PRID insertion, a 25-mg injection of PGF2α (Enzaprost; CEVA Santé Animale) at PRID removal, GnRH at 56 h after device removal and TAI 16 h later; (3) P4-Ovsynch+eCG: the same as P4-Ovsynch, but cows received 500 IU of equine chorionic gonadotropin (eCG; Syncrostim; CEVA Santé Animale) at PRID removal. At 10 d before mating start date (MSD), all cows that were ≥35 DIM were examined by transrectal ultrasound to assess presence or absence of a corpus luteum; body condition score (BCS) was also recorded. Pregnancy diagnosis was performed by transrectal ultrasonography 30 to 35 d after insemination. Overall pregnancy/AI (P/AI) was not different between groups (50.9, 49.8, and 46.3% for control, P4-Ovsynch, and P4-Ovsynch+eCG, respectively) but the 21-d pregnancy rate was increased by the use of synchronization (35.0, 51.7, and 47.2%, respectively). Compared with the control group, synchronization significantly reduced the interval from MSD to conception (34.6, 23.0, and 26.5 d, respectively) and consequently reduced the average days open (98.0, 86.0, and 89.0 d). Across all treatment groups, DIM at the start of synchronization affected P/AI (42.3, 49.5, and 53.9% for <60, 60-80, and >80 DIM, respectively), but neither parity (46.5, 50.4, and 48.4% for parity 1, 2, and ≥3, respectively) nor BCS (44.0, 49.4, and 58.6% for ≤2.50, 2.75-3.25, and ≥3.50, respectively) affected the likelihood of P/AI. Two-way interactions between treatment and DIM, parity, or BCS were not detected. In conclusion, the use of TAI accelerated pregnancy establishment in cows in a pasture-based system by reducing days open, but eCG administration at PRID removal did not affect P/AI.


Assuntos
Bovinos/fisiologia , Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/administração & dosagem , Leite/metabolismo , Progesterona/administração & dosagem , Reprodução/efeitos dos fármacos , Animais , Gonadotropina Coriônica , Corpo Lúteo/fisiologia , Dinoprosta/administração & dosagem , Detecção do Estro , Feminino , Cavalos , Inseminação Artificial/veterinária , Lactação , Ocitócicos/administração & dosagem , Paridade , Gravidez , Taxa de Gravidez , Distribuição Aleatória
4.
Obstet Gynecol ; 121(4): 851-855, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23635686

RESUMO

Umbilical cord blood, the blood remaining in the umbilical cord at birth, can be collected at birth and be a source of stem cells for a patient in need of a bone marrow transplant. Obstetricians and other health care practitioners are recognized as a patient's primary source for medical information affecting the mother and her neonate and frequently are asked to provide education and guidance regarding options of private and public cord blood banking. As the use of cord blood continues to grow in medicine and research uncovers more potential for cord blood, cord blood banking has become an important resource. The Stem Cell Therapeutic and Research Act has provided funding to expand public banking initiatives in the United States and to create a more ethnically diverse inventory of units. Private storage is not advocated unless there is an identified need in the family such that banked cord blood would offer a benefit. A recent report outlined the challenges of increasing participation and inventory, particularly among minority groups. Obstetricians and other health care practitioners should have a primary role in efforts to increase awareness of umbilical cord blood donation and be involved in initiatives to expand current public banking activities.


Assuntos
Bancos de Sangue , Sangue Fetal , Obstetrícia , Papel do Médico , Humanos , Modelos Teóricos , Setor Público
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