Sensor-Based and Visual Behavioral Profiling of Dry Holstein Cows Presenting Distinct Median Core Body Temperatures.

The consequences of heat stress during the dry period can extend into the postpartum period, affecting health and productivity in the subsequent lactation. We hypothesized that cows with distinct core body temperatures (CBTs) would exhibit disparate behaviors associated with different degrees of heat generation or dissipation. The primary objective was to investigate behavioral differences of dry Holstein cows ( = 50) classified as high-temperature (HT) or low-temperature (LT), based on median CBT during the summer months using visual observations and accelerometer technology.

Conceptus estrogen and prostaglandins provide the maternal recognition of pregnancy signal to prevent luteolysis during early pregnancy in the pig†.

Conceptus estrogens and prostaglandins have long been considered the primary signals for maternal recognition of pregnancy (MRP) in the pig. However, loss-of-function studies targeting conceptus aromatase genes (CYP19A1 and CYP19A2) and prostaglandin-endoperoxide synthase 2 (PTGS2) indicated that conceptuses can not only signal MRP without estrogens or prostaglandins but can maintain early pregnancy. However, complete loss of estrogen production leads to abortion after day 25 of gestation.

Establishment of the uterine microbiome following artificial insemination in virgin heifers.

Introduction: The concept of a sterile uterus was challenged by recent studies that have described the microbiome of the virgin and pregnant uterus for species including humans and cattle. We designed two studies that tested whether the microbiome is introduced into the uterus when the virgin heifer is first inseminated and whether the origin of the microbiome is the vagina/cervix.

Methods: The uterine microbiome was measured immediately before and after an artificial insemination (AI; Study 1; = 7 AI and = 6 control) and 14 d after insemination (Study 2; = 12 AI and = 12 control) in AI and non-AI (control) Holstein heifers.

The microbiome of the pregnant uterus in Holstein dairy heifers and cows assessed by bacterial culture and 16S ribosomal RNA gene sequencing.

Introduction: The possibility that there is a resident and stable commensal microbiome within the pregnant uterus has been supported and refuted by a series of recent studies. One element of most of the initial studies was that they were based primarily on 16S rRNA gene sequencing from bacteria. To account for this limitation, the current study performed both bacterial culture and 16S rRNA gene sequencing in a side-by-side manner (e.

Metritis and the uterine disease microbiome are associated with long-term changes in the endometrium of dairy cows†.

Cows with metritis (uterine disease) during the first 1 to 2 weeks postpartum have lower pregnancy rates when inseminated later postpartum (typically >10 weeks). We hypothesized that metritis and the disease-associated uterine microbiome have a long-term effect on endometrial gene expression. Changes in gene expression may inform a mechanism through which disease lowers pregnancy rates.

Factors influencing pregnancy per artificial insemination (AI) and embryonic mortality in Nelore females subjected to timed-AI in Brazil.

A greater understanding of factors influencing fertility is essential to improve pregnancy rates and reduce the occurrence of embryonic mortality in beef herds. The objective of the current study was to evaluate retrospective data of pregnancy per artificial insemination (P/AI) and pregnancy loss in Nelore females subjected to timed-AI (TAI) in Brazil. Data from 40,104 TAI collected from six breeding seasons (2016-2022) were analyzed, and the effects of animal category (e.

Systemic antibiotic treatment of cows with metritis early postpartum does not change the progression of uterine disease or the uterine microbiome at 1 month postpartum.

Background: Postpartum uterine disease (metritis) is common in dairy cows. The disease develops within 1 week after calving and is associated with microbial dysbiosis, fever, and fetid uterine discharge. Cows with metritis have a greater likelihood of developing endometritis and infertility later postpartum.

Inducing luteolysis prior to atresia of the first follicular wave by altering the interval to prostaglandin F administration after long-term progestin presynchronization.

A series of experiments was designed to evaluate treatment schedules for control of the estrous cycle in which luteolysis is induced prior to atresia of the first follicular wave following a long-term progestin presynchronization treatment in beef heifers. The overarching hypothesis was that the proportion of heifers undergoing luteolysis and expressing estrus following PG administration would be affected by the duration of treatment with an intravaginal progesterone-releasing insert (CIDR; 1.38 g progesterone) and/or by the interval from CIDR removal to prostaglandin F (PG; 500 μg cloprostenol) administration.

Characterizing the postnatal hypothalamic-pituitary-adrenal axis response of in utero heat stressed pigs at 10 and 15 weeks of age.

In utero heat stress alters postnatal physiological and behavioral stress responses in pigs. However, the mechanisms underlying these alterations have not been determined. The study objective was to characterize the postnatal hypothalamic-pituitary-adrenal axis response of in utero heat-stressed pigs.

Conceptus interferon gamma is essential for establishment of pregnancy in the pig†.

Establishment and maintenance of pregnancy in the pig is a complex process that relies on conceptus regulation of the maternal proinflammatory response to endometrial attachment. Following elongation, pig conceptuses secrete interferon gamma (IFNG) during attachment to the endometrial luminal epithelium. The objective here was to determine if conceptus production of IFNG is important for early development and establishment of pregnancy.

In utero heat stress alters the postnatal innate immune response of pigs.

The effects of in utero heat stress (IUHS) range from decreased growth performance to altered behavior, but the long-term impact of IUHS on postnatal innate immune function in pigs is unknown. Therefore, the study objective was to determine the effects of early gestation IUHS on the immune, metabolic, and stress response of pigs subjected to an 8 hr lipopolysaccharide (LPS) challenge during postnatal life. Twenty-four pregnant gilts were exposed to thermoneutral (TN; n = 12; 17.

Reproduction and reproductive tract morphology of male and female pigs whose mothers were heat stressed during the second month of gestation.

The primary objective was to assess the development of fetal gonads and measure the subsequent reproductive capacity of boars and gilts whose mother was either subjected to gestational heat stress (GHS) or thermoneutral (GTN; control) conditions during pregnancy. Gilts were subjected to either GHS (28 to 38 °C; 65% to 88% relative humidity [RH]; n = 30) or GTN (17 to 22 °C; 56% to 65% RH; n = 29) for the second month of gestation (a period that coincides with a critical window of gonadal development). A subset of GHS (n = 12) and GTN (n = 11) gilts was sacrificed immediately following treatment for the collection of pregnancy data.

Evaluation and mitigation of the effects of in utero heat stress on piglet growth performance, postabsorptive metabolism, and stress response following weaning and transport.

In utero heat stress (IUHS) increases the energy requirements of pigs during postnatal life, and this may compound weaning and transport stress. The study objective was to evaluate and mitigate the negative effects of IUHS following weaning and transport through the provision of a nutrient-dense (ND) nursery diet formulated to meet the greater energy requirements of IUHS pigs during the first 14 d postweaning and transport. Twenty-four pregnant gilts were exposed to thermoneutral (TN; n = 12; 17.

Stress, strain, and pregnancy outcome in postpartum cows.

Stress affects the productivity and fertility of cattle. Stress causes strain and individual animals experience different amounts of strain in response to the same amount of stress. The amount of strain determines the impact of stress on fertility.

Evaluation of cervical and uterine size, at 4 weeks postpartum, as a predictor of subsequent fertility in Jersey cattle.

Uterine and cervical size of Holstein dairy cows is reported among reasons for a decline in dairy cow fertility. Therefore, the objectives of this study were to (a) determine whether size of the cervix and uterus at 4 weeks postpartum impacted subsequent fertility at first service in Jersey cattle, (b) determine whether progesterone level at 4 weeks postpartum impacted cyclicity and (c) the association of the presence of corpus luteum and uterus and cervix size. Body condition scores at calving, presence of postpartum diseases, parity number and milk weights were taken from lactating Jersey dairy cows (N = 147) for 28 days postpartum.

Concurrent and long-term associations between the endometrial microbiota and endometrial transcriptome in postpartum dairy cows.

Background: Fertility in dairy cows depends on ovarian cyclicity and on uterine involution. Ovarian cyclicity and uterine involution are delayed when there is uterine dysbiosis (overgrowth of pathogenic bacteria). Fertility in dairy cows may involve a mechanism through which the uterine microbiota affects ovarian cyclicity as well as the transcriptome of the endometrium within the involuting uterus.

Evaluating the Effects of In Utero Heat Stress on Piglet Physiology and Behavior Following Weaning and Transport.

The study objective was to determine whether in utero heat stress (IUHS) affects piglet physiology and behavior following common production practices. A total of 12 gilts were confirmed pregnant and allocated to either heat stress (HS; = 6) or thermoneutral (TN; = 6) conditions on day 30⁻60 of gestation. At weaning (22.

In utero heat stress causes reduced testicular area at puberty, reduced total sperm production, and increased sperm abnormalities in boars.

In utero stress has been shown to negatively affect intact male rats and mice, though very little research has been conducted in boars. The objectives of the present studies were to determine the effects of in utero heat stress (IUHS) on postnatal development and the response to postnatal heat stress of boars. Ten boars were selected at weaning from litters subjected to IUHS or in utero thermoneutral (IUTN) during 30-60 days of gestation.

The transcriptome of the endometrium and placenta is associated with pregnancy development but not lactation status in dairy cows.

Infertility in lactating dairy cows is explained partially by the metabolic state associated with high milk production. The hypothesis was that lactating and nonlactating cows would differ in endometrial and placental transcriptomes during early pregnancy (day 28 to 42) and this difference would explain the predisposition for lactating cows to have embryonic loss at that time. Cows were either milked or not milked after calving.

Heat stress in pregnant sows: Thermal responses and subsequent performance of sows and their offspring.

Seasonal infertility is a significant problem in the swine industry, and may be influenced by photoperiod and heat stress. Heat stress during gestation in particular affects pregnancy, resulting in long-term developmental damage to the offspring. This review summarizes what is known about how heat stress on the pregnant sow affects lactation and her offspring.