Effect Of Parity Research Articles

Associations of parity and lactation stage with the order cows enter the milking parlor

To explore the effect of lactation stage and parity on the milking order of cows, we collected milking order data of all lactating cows (n = 251) over a period of 12 wk in one commercial Swedish dairy cow herd using a herringbone milking parlor. Cows were kept in 2 housing groups (G1 and G2) and moved from G1 to G2 at approximately mid lactation. Two analyses were conducted to investigate if lactation stage (early: 2–49 d in milk, mid: 50–179 d in milk, and late ≥180 d in milk) and parity are associated with the entrance order to the parlor or a preference of entering a new milking line first. In G1 and G2, cows in first parity entered the milking parlor earlier than cows in higher parities. In addition, in G1 cows in early lactation entered the milking parlor earlier than cows in later lactation. Similar effects were observed for the preference of entering a new milking line first. No effect of mid versus late lactation could be observed in either G1 or G2. The study also found that cows tend to keep their rank within the milking order constant. The results of the study indicate that cows of presumably lower hierarchy (first parity and early lactation) leave the waiting area earlier compared with other cows. This should be considered when planning grouping strategies and preventive measures against mastitis pathogen transmission.

EFFECT OF NON-GENETIC FACTORS ON PRODUCTIVE AND REPRODUCTIVE PERFORMANCE IN CROSSBRED COWS MAINTAINED AT LIVESTOCK EXPERIMENT STATION, QADIRABAD DISTRICT SAHIWAL

The present study was undertaken to evaluate the effect of non-genetic factors such as the period of calving, season of calving, and parity on economically important productive and reproductive traits in crossbred cows (Holstein Friesian × Sahiwal) maintained at livestock experiment station Qadirabad Sahiwal, Pakistan. The study ranged from 1995 to 2014 (20 years). The duration of 20 years was divided into 4 periods (P1, P2, P3, and P4) with each period consisting of five years. Each year was further divided into three seasons winter (November-February), summer (March- June), and spring (July-October) based on geo-climatic conditions prevailing in the region. The parameters used as indicators of reproductive performance in this study were age at first calving (AFC), days open (DO), dry period (DP) and calving interval (CI). The overall least squares mean and standard errors for these reproductive parameters were 1235.23±45.81, 202.08±6.75, 178.4±6.85 and 482±5.97 days, respectively. While productive parameters were lactation milk yield 305 d(LMY), daily milk yield, and Lactation length (LL), and the least squares mean and standard errors of these were 2471.44±78.44 kg,8.07±0.27kg and306.22±4.84 days, respectively. Twenty years (20) data of 641 lactation records of crossbred cows representing the variance analyses indicated that significant (P≤0.05) effect of season of calving on age at first calving (AFC), days open (DO), lactation length (LL), and lactation milk yield (LMY). Least-squares means illustrated that the period of calving also significantly (P≤0.00) affects lactation milk yield (LMY) lactation length (LL) and dry period (DP). Similarly, a significant (P≤0.00) effect of parity on lactation milk yield (LMY), dry period (DP), days open (DO), and calving interval (CI) was noted. It is therefore concluded that the reproductive and productive performance of these crossbred cows is affected by some non-genetic factors and breeders must consider the season of calving, period of calving and parity in the management program because they greatly affect the farm productivity and profitability and they must select animals with higher breeding values to be the parent of the next generation.

Effects of long-acting injectable progesterone supplementation at early dioestrus on pregnancy maintenance in beef and dairy recipient cattle.

We tested in the present study the hypothesis that supplementation with long-acting P4 (iP4) at different times of the initial dioestrus improves pregnancy rates in dairy and beef recipients submitted to fixed-time embryo transfer (FTET). Recipients from commercial farms had their oestrous cycle synchronized with an E2/P4-based protocol in three experiments (Exp. 1 to 3). In Exp. 1, dairy heifers (n = 76) and cows (n = 104) were randomly assigned to two experimental groups: the control group (n = 89) and the iP4D4 group (n = 91). For Exps. 2 and 3, suckled beef recipients were used. In Exp. 2, recipients were assigned to two experimental groups: Control group (n = 147) and iP4D7 group (n = 144); whereas in Exp. 3, recipients were randomly assigned to three experimental groups: Control group (n = 85), iP4-D4 group (n = 86) and iP4D7 group (n = 81). Recipients in the iP4D4 and iP4-D7 groups received an i.m. administration of 150 mg iP4, on D4 or D7 (D0 was the day of expected oestrus). On D7, all recipients were evaluated by transrectal ultrasonography and those that had a CL received a fresh or vitrified invitro-produced embryo. In Exp. 2 and 3, the CL area was also determined by ultrasonography at the time of FTET. The pregnancy diagnosis was performed at 30 days in Exp. 1, 57 days in Exp. 2, and between 40 and 72 days of pregnancy in Exp. 3. In Exp. 1, the pregnancy rate did not differ (p > .1) between the Control group (38.2% [34/89]) and iP4D4 group (49.5% [45/91]); yet, a parity effect indicated a greater (p < .05) pregnancy rate in heifers (57.9% [44/76]) than cows (30.8% [32/104]). In Exp. 2, the pregnancy rate was greater (p < .05) in the iP4D7 group (45.0% [65/144]) than in the Control group (34.0% [50/147]). Also, a greater (p = .08) pregnancy rate was observed for recipients with a small CL (≤2.75 cm2 ) that were treated with iP4 on the day of FTET than the control recipients (46.4% [32/69] vs. 32.6% [28/86]). In Exp. 3, no significant effects (p > .1) of the treatment group or CL size were detected on pregnancy rates at days 30 and 60. In conclusion, the beneficial effects of iP4 supplementation at early dioestrus on pregnancy maintenance may vary according to the experimental conditions, but its use at the time of FTET can be used as an alternative to enhance the fertility of beef recipients in challenging conditions in commercial herds.

The Effect of High Parity on the Occurrence of Anaemia in Pregnant Women.

To compare high-para and low-para women with respect to haematological findings, determinants, and consequences secondary to anaemia. Descriptive cohort study. Place and Duration of the Study: Maternity and Child Hospital, Hail, Saudi Arabia and Specialist Care Hospital (private), Islamabad, Pakistan, from April 2022 to April 2023. The study population comprised of pregnant women in the last trimester, with the exception of those women who had more than one fetus and history of haematological disease. Purposive non-probability sampling technique was adopted. Hospital data were retrieved retrospectively for the past obstetrical, contraception usage, and supplement history. Blood parameters, type of delivery, and maternofetal complications were noted down. For qualitative-variable and quantitative-variable comparisons, Chi-square test and t-test were applied, respectively. Significance level was kept at p ≤0.05. The frequency of severe anaemia in high-para was 52%. High parity and anaemia had a significant dose-response relationship (p <0.05). There was a significant difference (p <0.05) in blood parameters between high-para and low-para groups. Main determinants identified for anaemia were lack of intake of iron-rich food (36%) followed by inadequate intake of oral iron (25%). Preterm birth (68%) and post-partum haemorrhage (96%) were significantly associated (p <0.05) with high parity. There was a significantly high proportion (83%) of high-para women with more than 3 cesarean deliveries and admissions in ICU. High parity and anaemia had a significant dose-response relationship. High parity was the main determinant of maternal and fetal admissions in ICU. Parity, Comparison, Maternal anaemia, Haematological findings, Diet, Contraception, Cost-effective.

Evaluation of trait preferences and effect of parity, season and lactation stage on production performance of indigenous dairy cow in kaffa zone, southwest Ethiopia

The current research focused on the effects of parity, season, and lactation stage on the milk yield of indigenous dairy cows in selected districts of the Kaffa Zone of southern Ethiopia. The districts of Gesha and Chena were purposefully chosen. The study design for the 384 household surveys was a cross-sectional survey with a simple random sample approach as the sampling method. Following the survey, 192 lactating cows were chosen for a monitored investigation to track nighttime and morning milk supply. In addition to key informants and focus group discussions, primary and secondary data were obtained via a semi-structured questionnaire, interview, and field observation. The most favored features functioning as selection criteria were those favored for production, reproduction, physical appearance, physiological function, and temperament, in that order. Evening milk yield (EMY), mornning milk yield (MMY), daily milk yield (DMY), lactation length (LL) and lactation milk yield (LMY) were 0.91 ± 0.033 L, 1.22 ± 0.037 L, 2.125 ± 0.07 L, 6.36 ± 0.116 months, and 427.10 ± 20.678 L, respectively, with significant difference (p < 0.01) amongst districts, parity, and season. However, there was no significant variation between studies in EMY, MMY and DMY. Significantly higher values of production performances were recorded for interaction among districts, parity, and season. The study also revealed that interaction between district (Gesha) and parity (third), which were signficantlly higher for EMY, MME, DMY, LL, and LMY 1.50 L, 2.00 L, 3.50 L, 8.10 months, and 850.50 L, respectively. The same trend also observed for interaction among district (Gesha), season (wet), and parity (third), which were obtained to be highly significant values of EMY, MMY, DMY, LL, and LMY were 1.35 L, 1.75 L, 3.10 L, 7.65 months, and 716.80 L, respectively. The study region has a large population of indigenous dairy cows and produces higher yields than the national average. However, it falls short of the worldwide production benchmarks, and the trait preferences used as a selection criterion were based on the farmers' indigenous knowledge. Measures to enhance production abilities must be incorporated and selection criteria must be modernized.

Impact of parity on pelvic floor morphology and function: A retrospective study.

To analyze the effect of parity on pelvic floor morphology and function during the postpartum period. A total of 971 participants, who attended the Fujian Maternity and Child Health Hospital (Fuzhou, China) between December 2019 and August 2021, were included. All participants were assessed using the modified Oxford scale (MOS), pelvic floor surface electromyography, and 3-dimensional pelvic floor ultrasound to assess pelvic floor morphology and function. Multivariate analysis revealed no differences among primipara, deuteripara, and tertipara in pre-baseline rest, phasic contraction, endurance contraction, post-baseline rest, and MOS, except for tonic contraction (P = .020), the amplitude of which was lower in primipara than in deuteripara in post hoc comparison (P = .008). Differences in bladder neck presentation and bladder neck descent were statistically significant in multivariate analysis (P = .002, P = .001, respectively), with the value of bladder neck presentation in primiparas being greater than that of deuteriparas and tertipara (P = .002, P = .008, respectively), and the value of bladder neck descent was lower than that of deuteripara and tertipara in further post hoc comparisons (P = .002, P = .003, respectively). Functional impairment was not statistically associated with parity according to the MOS score or surface electromyography. However, parity was significantly correlated with descent of the bladder neck, and most of the effects appeared to occur during the first delivery.

Abstract 13041: Effects of Parity on Arterial Stiffness Persists Into Old Age, Independent of Chronological Ageing

Introduction: Persistent effects of reproductive factors on vascular ageing, over chronological ageing, as examined through objective measurements of arterial stiffness, are rarely studied. Hypothesis: We hypothesized that the effects of parity and maternal age at first birth (AFB) on vascular ageing will persist over time independent of chronological ageing, in older Asian women. Methods: Among a community-based cohort of older Asian adults without cardiovascular disease, we prospectively studied demographics, parity, AFB, and cardiovascular risk factors, at baseline and 5-year examination timepoints. Arterial stiffness was measured through pulse wave velocity (PWV) using a cuff-based auscultatoric oscillometric pulse wave analysis machine. Results: 170 women (baseline mean age 60.76±13.75 years) were included. Parity ranged from 0 to 8 (mean parity 2±1.3). AFB ranged from 18 to 44 (mean age 28±4.4) years. By regression, univariate determinants of 5-year PWV were parity (β=0.491, p=&lt;.001), αFB (β=-0.107, p=.011), baseline age (β=3.884, p=&lt;.001), body mass index (βμΙ) (β=0.147, p=.006), waist circumference (β=0.076, p=&lt;.001), diabetes (β=1.681, p=&lt;.004), hypertension (β=2.383, p=&lt;.001), dyslipidemia (β=2.220, p=&lt;.001), 5-year age (β=3.886, p=&lt;.001),waist circumference (β=0.085, p=&lt;.001), diabetes (β=1.723, p=.001), hypertension (β=2.485, p=&lt;.001). Based on multivariate regression, parity (β=0.345, 95% CI 0.105, 0.586, p=.005), but not AFB, was independently associated with 5-year PWV, independent of age. Conclusions: Parity and AFB correlated with PWV, a marker of arterial stiffness, in old age in Asian women. Accounting for chronological ageing and clinical factors across 5 years, parity exerted a persistent independent effect on arterial stiffness in older women. Other biological factors surrounding parity in these women apart from traditional cardiovascular risk factors may explain these observations.

PSII-9 Circulating Cytokine Profiles of Bos Indicus Cattle Prior to Artificial Insemination in Relation to Pregnancy Status

Abstract Cytokines and chemokines (cytokines with chemotactic activity) influence inflammatory responses and can upregulate pro- or anti-inflammatory immune responses and influence fertility. The aim of this study was to characterize the circulating cytokines of Bos indicus females prior to fixed-timed artificial insemination (FTAI). Bos indicus females on operations within a 20-mile radius were subjected to the 7-day CO-Synch + CIDR protocol on day (d) -9 and FTAI on d 0. Blood samples were collected on d -9 (CIDR IN), d -2 (CIDR OUT), and d 0 (AI). Cattle were body condition scored (BCS) on d 0. Pregnancy status was determined by transrectal ultrasonography for resulting non-pregnant females (n = 44) and resulting pregnant females (n = 34). Cytokine analyses on blood plasma samples were conducted using the RayBiotech Quantibody Bovine Cytokine Array Q1 kit per manufacturer's instructions. Cytokines and chemokines measured included interferon alpha (IFNa), interferon-gamma (IFNg), interleukin (IL)1a, IL1F5, IL13, IL21, chemokine-ligand (CXCL) 9, CXCL10, macrophage inflammatory protein (MIP)1b, and tumor necrosis factor alpha (TNFa). Data were analyzed using PROC GLM in SAS 9.4 with fixed effects for pregnancy status, ranch, day, and parity. Body condition scores did not significantly differ by pregnancy status (P &amp;gt; 0.05). There were no differences in cytokine concentrations by day of the synchronization protocol or between cows and heifers (P &amp;gt; 0.05). There were differences by location (P &amp;lt; 0.05) for most cytokines except MIP1b and TNFa. Circulating concentrations of the pro-inflammatory cytokines IFNg, IL1a, and TNFa were greater (P &amp;lt; 0.05) in resulting non-pregnant females compared with pregnant females (2,323.5 ± 260.5 vs. 1,502.8 ± 246.8 pg/mL, 894.6 ± 96.8 vs. 598.3 ± 91.7 pg/mL, and 6,052.6 ± 627.4 vs. 4,156.6 ± 594.3 pg/mL, respectively). Circulating concentrations of the chemokines CXCL9, CXCL10, and MIP1b were also greater (P &amp;lt; 0.05) in resulting non-pregnant females compared with pregnant females (4,887.0 ± 538.3 vs. 2,905.3 ± 509.8 pg/mL, 12,167.3 ± 1,496.2 vs. 6,295.4 ± 1,417.2 pg/mL, 586.4 ± 56.8 vs 324.4 ± 53.8 pg/mL, respectively). Interestingly, circulating concentrations of the anti-inflammatory cytokines IL13, IL1F5, and IL21 were greater (P &amp;lt; 0.05) in resulting non-pregnant females compared with pregnant females (11,147.7 ± 1,009.9 vs. 6,752.1 ± 956.6 pg/mL, 1,189.3 ± 111.7 vs. 744.5 ± 105.8 pg/mL, and 1,1153.6 ± 898.0 vs. 8,409.7 ± 850.6 pg/mL, respectively). No differences by pregnancy status were found for concentrations of IFNa (P = 0.13). These results suggest that an increase in circulating cytokines and chemokines prior to FTAI negatively impacts fertility in Bos indicus cattle. Future research is necessary to determine the threshold of circulating cytokine concentrations that subsequently impact pregnancy establishment and maintenance.

Analysis of milk production and calving records in semi-intensively managed dairy herd in Zambia

This study was undertaken to provide empirical evidence for some reproductive performance traits in a dairy herd managed under a semi-intensive production system in Zambia. Milk production and calving records on 106 milking cows were analysed over a 12-year period involving Friesian, Jersey, Friesian x Jersey, Friesian x Simmental and Jersey x Sussex breeds. With an average parity order of 4.4, the average total milk production per lactation, average daily milk production, calving interval, and calving rate were 1,996 ± 493.5Kg, 7.9 ± 2.6Kg, 473.1 ± 138.5 days, and 77.2% respectively. Milk production was significantly higher from mid November to April compared to other months and this corresponds to the significant seasonal effect observed. A significant breed effect was found with total milk yield per lactation and average milk yield. There were significant parity effects on average daily milk production and calving interval. However, there was no significant breed effect on the calving interval. The correlation of average milk yield with calving interval was -0.26, and the parity order with average milk yield was 0.65. Friesian x Jersey crossbred showed heterosis for milk production (48.3%) and calving interval (11.4%). Breeding strategies can, therefore, be targeted at using Jersey x Friesian crossbred for the emergent smallholder farmers.

PSII-14 The Effect of Increasing Soluble Dietary Fiber and the Addition of a Stimbiotic in Gestation on Sow Productivity in a Prrs and Non-Prrs Challenge

Abstract This sow study evaluated the effect that sugar beet pulp (SBP), a soluble fiber source, and a stimbiotic (Signis; AB Vista) can have on sow productivity and health when fed in gestation. A stimbiotic is an additive that stimulates fiber-degrading microbiome, resulting in an increase in fiber fermentability even though the additive itself contributes limited small chain fatty acid production. A commercial gestation barn with two feeding lines was utilized to feed sows (n = 2173) two dietary treatments from d 30 to d 90; a corn, soy, soy hulls with (HSDF) or without (LSDF) SBP (50 kg/t) plus stimbiotic (100 g/t) and from d 90 to entering the farrowing pen the LSDF diet with or without a stimbiotic (100 g/day). Sows were fed 2.0 kg per day providing the following fiber intake levels/day, HDSF: TDF; 266g, SDF 55g, IDF, 211g and LDSF: TDF; 240g, SDF 40g, IDF, 200g. The following variables were measured; total born, live born, still born, mummies, pre-weaning mortality, pigs weaned per sow, prolapse rate and sow mortality/culls. A proportion of sows (n = 81) were moved to a GESTAL system for lactation and intake recorded per gestation treatment. During the study the farm became PRRS positive and any sows that farrowed while the farm was PRRS positive were identified as PRRS positive sows and included as a factor. Data were analyzed with ANOVA evaluating the effects of fiber, parity, and PRRS using the fit model platform in JMP16. Significant treatment means were separated using Student’s t-tests, with significance accepted at P ≤ 0.05. Results showed that for born alive there was an interaction between treatment and parity (P =0.02) and treatment and PRRS (P &amp;lt; 0.05) with the HDSF diet increasing born alive in parity 1 (+1.30 pigs; P = 0.03) and parity 2 (+0.71 pigs; P = 0.08) with no effect in parity 3+. HDSF improved born alive in non PRRS pigs (+1.01 pigs; P &amp;lt; 0.01) and had no effect in PRRS pigs. There was a tendency for HDSF program to reduce stillborn (8.8% v 7.4%; P = 0.09) but had no effect on mummies. There was a tendency to increase in pigs weaned with the HSDF treatment (9.15 v 8.86; P = 0.07) with no effect on sow mortality/culls. There was no effect of treatment on prolapses. On the sub-sample of sows recorded in lactation those sows (Parity 2+) that had been on the HSDF in gestation showed an increased ADFI (5.36 kg v 6.02 kg; P = 0.01) compared with the LSDF. It can be concluded that sow productivity can be improved by increasing the fermentative capacity of the gestation feed through the combination of adding a soluble fiber such as SBP along with a stimbiotic.

Modeling daily yields of milk, fat, protein, and lactose of New Zealand dairy goats undergoing standard and extended lactations

This study aimed to assess the milk production data for New Zealand dairy goats in either a standard lactation (SL; ≤305 d in milk [DIM]) or extended lactation (EL; >305 and ≤670 DIM) using a random regression (RR) with third- and fifth-order Legendre polynomials, respectively. Persistency of EL was defined as (B/A) × 100, where A was the accumulated yield from d 1 to 305, and B was the accumulated yield from d 366 to 670. On average, goats in SL produced 1,183 kg of milk, 37 kg of fat, 37 kg of protein, and 54 kg of lactose. The average production of milk, fat, protein, and lactose in EL were 2,473 kg, 78 kg, 79 kg, and 112 kg, respectively. The average persistences for milk, fat, protein, and lactose yields during EL were 98%, 98%, 102%, and 96%, respectively. The relative prediction errors were close to 10% and the concordance correlation coefficients >0.92, indicating that the RR model with Legendre polynomials is adequate for modeling lactation curves for both SL and EL. Total yields and persistency were analyzed with a mixed model that included the fixed effects (year, month of kidding, parity, and proportion of Saanen) as covariates and the random effects of animal and residual errors. Effects of year, month of kidding, and parity were significant on the total yields of milk, fat, protein, and lactose for both SL and EL. The total milk yield of first-parity goats with SL was 946 kg and the total milk yield of second-parity goats with SL was 1,284 kg, making a total of 2,230 kg over 2 years. The total milk yield of a first-parity goat with EL was 2,140 kg. Thus, on average, a goat with SL for the first and second parity produced 90 kg more milk than a first-parity goat subjected to EL. However, a second-parity goat subjected to EL produced 43 kg more milk (2,639 kg) than a goat with SL following the second and third parity (1,284 kg + 1,312 kg). These data, along with the various other benefits of EL (e.g., fewer offspring born and reduced risk of mastitis, lameness, and metabolic problems in early lactation), indicate that EL as a management strategy holds the potential to improve dairy goat longevity and lifetime efficiency without compromising milk production.

Are pregnancy and parity associated with telomere length? A systematic review

BackgroundWomen's reproduction requires increased energy demands, which consequently may lead to cellular damage and aging. Hence, Telomere Length (TL), a biomarker of biological aging and health status may possibly serve as a biomarker of reproductive effort. The aim of this systematic review is to evaluate telomere dynamics throughout pregnancy and the association between parity and TL.MethodsA systematic search was conducted across seven databases including CINAHL, Cochrane, PsycINFO, Proquest, PubMed; Scopus; and Web of Science, using keywords and MeSH descriptors of parity and TL. Predefined inclusion and exclusion criteria were used to screen abstracts and titles. After the removal of duplicates, 3431 articles were included in the primary screening, narrowed to 194 articles included in the full-text screening. Consensus was reached for the 14 studies that were included in the final review, and the Newcastle–Ottawa scale (NOS) was utilized to assess the quality of the selected studies. A mini meta-analysis utilized JASP 0.17.3 software and included 4 applicable studies, comprising a total of 2564 participants to quantitatively assess the estimated effect size of parity on TL.ResultsOf the 11 studies reviewed on parity and TL, four demonstrated a negative correlation; one – a positive correlation and six -found no correlation. Studies demonstrating a negative correlation encompassed rigorous methodological practices possibly suggesting having more children is associated with enhanced telomere attrition. Of the four longitudinal studies assessing telomere dynamics throughout pregnancy, most found no change in TL from early pregnancy to postpartum suggesting pregnancy does not affect TL from early pregnancy to early postpartum. The meta-analysis revealed a negative, yet, non-significant effect, of the estimated effect size of parity on TL(ES = -0.009, p = 0.126, CI -0.021, 0.03).ConclusionsStudies assessing pregnancy, parity and TL yielded mixed results, most likely due to the different research methods utilized in each study. Improvements in study design to better understand the short-term effects of pregnancy on TL and the effect of parity on TL over time, include precise definitions of parity, comparisons of different age groups, inclusion of reproductive lifespan and statistically adjusting for potential confounders in the parity and TL relationship.

Hind feet position score: A novel trait to genetically reduce lameness incidence

Lameness is an important health and welfare issue that causes considerable economic losses in dairy herds. The objective of this study was to investigate whether the hind feet position score (HFPS) can be used as an auxiliary trait for genetic evaluation of lameness. The HFPS is evaluated by visual scoring of the position of both the hind-digits to the mid-line of the cow's body. The higher the heel height of the lateral claw, the higher is the HFPS, and the higher is the risk for development of lameness. In total, 3,478 records from 1,064 Fleckvieh cows from 35 farms were obtained between September 1, 2021, and March 5, 2022. Data collection was carried out by the regional milk recording organizations. Hind feet position was scored visually by trained personnel during routine milk performance testing in the milking parlor using a 3-class scoring system: score 1 = 0° to <17° indicating a balanced heel height of both the medial and the lateral claw; score 2 = angle of 17° to 24°; score 3 = angle of >24°. After all cows had been milked, locomotion scoring was performed for each animal using a 5-class scoring system with locomotion scores ranging between 1 (normal) and 5 (severely lame). Using HFPS, sensitivity and specificity were 69.5% and 66.8%, respectively, for detecting lameness defined by locomotion score ≥2. For genetic analyses, a bivariate linear animal model was fitted with fixed effects of herd, parity, lactation stage, and classifier, and random effects of animal and permanent environment. Heritabilities for HFPS and locomotion score were 0.07 and 0.10, respectively, and the genetic correlation between the 2 traits studied was 0.80. These results suggest that the HFPS could be used for genetic evaluations to reduce lameness incidence in dairy cattle.

Parity and housing effects on the behavioural and hypothalamic–pituitary–adrenal axis responses of pregnant ewes

It is common in many countries for sheep to be housed during winter from mid-gestation until lambing to protect ewes and lambs from adverse conditions and improve late gestation nutritional management. Keeping ewes indoors, however, has its own challenges as the animals may be mixed with unfamiliar conspecifics, have limited floor and feeding space, experience changes to their diet and increased handling by humans. Therefore, the objective of this study was to investigate the effect of variation in housing management (space allowance and social stability) on the behaviour and hypothalamic–pituitary–adrenal (HPA) axis responses of pregnant ewes from mid-to-late gestation (weeks 11–18 of pregnancy). Seventy-seven ewes (41 primiparous, 36 multiparous) were divided into two groups: ‘Control’ and ‘Restricted space and mixed’ (RS-Mix), where RS-Mix ewes were allocated half the amount of space (1.27 vs 2.5 m2 for RS-Mix and Control, respectively) and feedface (concentrate feeder space) allowance (36 vs 71 cm per ewe) given to the Control group and were also subjected to two social mixing events. Aggressive behaviour at the feedface and time spent standing, lying, walking, feeding and ruminating were recorded and faecal samples were collected for assessment of faecal glucocorticoid metabolite (FGM) concentrations. Higher aggression was observed in RS-Mix ewes during the first week of observation (P = 0.044), which gradually declined to the same level as Control ewes by the end of the study (P = 0.045). RS-Mix ewes were significantly less likely to be able to freely join the feedface compared to Controls (P = 0.022). No other significant treatment effects on aggressive behaviour or FGM during gestation were found. RS-Mix ewes displayed significantly higher ruminating behaviour at week 18 of gestation compared to Control ewes (P < 0.001), but no other effects were seen on general pen behaviour. However, the effect of indoor housing had a significant impact on primiparous ewes, who had lower weight gain (P = 0.015) and higher FGM concentrations (P = 0.014) compared to multiparous ewes regardless of treatment group. The data suggest that, although no sustained effects on behaviour or HPA axis responses were seen with the differences in space and feeder allowance or social stability at the levels used in this study, inexperienced (primiparous) ewes may find indoor housing more stressful; and are less able to adapt compared to multiparous ewes. These effects may influence the behaviour of the ewe at lambing time, and her offspring.

SAT270 Parity Increases Corticosterone Response To Restraint-induced Stress After Mild Blast Traumatic Brain Injury In Mice

Abstract Disclosure: S. Anisowicz: None. M. Bodemeier Loayza Careaga: None. T. Wu: None. Background: Traumatic brain injury (TBI) is a common problem worldwide, with an estimated incidence of 69 million injuries per year. In the US military, one of the most common forms of TBI during operational deployments after Sep 11, 2001 was the blast TBI, thought to be responsible for over 80% of TBI sustained in theater. One consequence of TBI is dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis. HPA axis dysregulation is linked to increased risk for psychiatric disorders. Furthermore, prior research has shown that TBI may dysregulate the HPA axis in a sex-dependent manner. Throughout a female’s life span, there are several sentinel events of hormonal consequence, including pubarche, menopause, and parity, which are known to be times of changes in risks for psychiatric disorders. Objectives: The role of parity on TBI response has not yet been studied, though parity has been shown to decrease fear-related behaviors and decreased corticosterone load in multiparous mice when compared to nulliparous (NP) controls. Our objective is to determine if parity alters corticosterone (CORT) response to restraint, a mild psychological stressor, in mice exposed to mild blast TBI (mbTBI). Methods: One hundred thirteen NP or primiparous (PP) C57Bl6/J mice were randomly assigned to receive sham or mbTBI. Among those that received mbTBI (19.2 ± 0.12 psi), 32 were NP and 24 were PP. Among sham mice, 32 were NP and 26 were PP. All mice received isoflurane anesthesia prior to sham or mbTBI treatment. At 7-8 days after mbTBI, half the mice within each treatment group were subjected to a mild 20-min restraint before being anesthetized by CO2 followed by collection of trunk blood. Serum was harvested and analyzed for CORT concentrations by ELISA (Enzo Life Sciences). Results: All mice that received mbTBI had a longer (p&amp;lt;0.05) righting time compared to those that did not. There was no main effect of parity in the righting time (p&amp;gt;0.1). PP mice who experienced mbTBI demonstrated a greater (p&amp;lt;0.05) CORT response to restraint (157.3 ± 21 pg/mL) when compared to NP mice (95.9 ± 7.2 pg/mL). CORT response to restraint did not differ (p&amp;gt;0.1) between NP and PP mice who did not experience mbTBI (96.1 ± 7.6 vs 109.2 ± 16 pg/mL). Conclusions: Our data indicates that mbTBI alters HPA axis reactivity in PP mice compared to NP mice, increasing the CORT response to restraint induced stress. Parity alone did not alter CORT response to restraint stress or baseline CORT levels. The results of our finding highlight the importance of parity as a factor in an individual’s lifespan. Presentation: Saturday, June 17, 2023

Analysis of Reproduction Performance Traits in Sows of the CG36 Hybrid Line, Including the Effect of Selected Factors and Phenotypic Correlations

In Poland, despite a decline in the pig population, pork consumption invariably remains high. For this reason, it is important to search for a potential reduction in pig production costs. One of the feasible solutions is to use sows of hybrid lines. Currently, several sow lines are available on the Polish market, such as CG36 (Choice Genetics). The aim of this study was to determine the level of reproduction performance in this line considering the effect of parity and farrowing season. Additionally, coefficients of phenotypic correlations between analysed reproduction performance parameters were determined. The experimental material comprised 112 females inseminated with semen of a boar of the Excelium line (Choice Genetics), which produced 336 litters. The investigated population was characterised by a high level of reproduction traits and young age at first farrowing (AFF), while the number of piglets born alive (NBA), the number of piglets weaned per litter (NW), and the number of piglets weaned per sow per year (PWSY) reached high, economically advantageous levels. Primiparous sows produced and reared lower numbers of piglets than multiparous sows, which indicates the need to maintain an adequate herd structure, with a maximum share of gilts at 30%. No effect of the season on values of reproduction traits was found, which shows optimal environmental conditions in the animal housing where the pigs were kept. Dependencies between the analysed traits confirmed the results reported by other authors, where NBA was highly positively correlated with LW, although LW increased with an increase in NBA. No correlations were found between PWSY and the other traits. In turn, the observed coefficients of phenotypic correlations indicate that in order to reduce AFF in CG36 sows, it is necessary to control FI.

Effects of butyl benzyl phthalate exposure during pregnancy and lactation on the post-involution mammary gland

The mammary gland undergoes comprehensive reorganization during pregnancy, lactation, and subsequent involution. Following involution, the mammary gland has structural and functional differences compared to the gland of a nulliparous female. These parity-associated changes are regulated by hormones and may be vulnerable to endocrine-disrupting chemicals (EDCs). In this study, we evaluated the long-term effects of butyl benzyl phthalate (BBP), an estrogenic plasticizer, on the parous mouse mammary gland. Pregnant BALB/c mice were treated with 0, 3, 500, or 18000 µg/kg/day BBP throughout both pregnancy and the lactational period. The litters born to these females were evaluated for litter size and growth. The parous females were then kept for five weeks following weaning of the pups, during which period there was no exposure to BBP. After five weeks of post-weaning, mammary glands were collected and assessed for changes in histomorphology, steroid receptor expression, innate immune cell number, and gene expression. An unexposed age-matched nulliparous control was also evaluated as a comparator group. BBP increased male and female pup weight at puberty and female offspring in adulthood. BBP also altered innate immune cells in the post-involution mammary gland, reducing the effect of parity on macrophages. Lastly, BBP modestly increased mammary gland ductal complexity and periductal structure, but had no effect on expression of estrogen receptor, progesterone receptor, or a marker of proliferation. These results suggest that BBP may interfere with some effects of parity on the mouse mammary gland and induce weight gain in exposed offspring.

Relationships of beta-casein genetics with production, fertility, and survival of purebred organic Holstein dairy cows

The objective of this study was to compare β-casein genotype of purebred certified-organic Holstein cows, and their effect on production, fertility, and survival. Holstein cows (n = 1,982) from 13 certified-organic dairy herds from the western, midwestern, and northeastern United States were genomically tested with CLARIFIDE Plus (Zoetis) for β-casein genotype. Two hundred fourteen cows were A1A1 (11%), 848 cows were A1A2 (43%), and 920 cows were A2A2 (46%). In total, 2,249 lactation records, 1,025 from the first parity and 1,224 records during second and greater parities were used. Test-day milk, fat, and protein production (305-d) and somatic cell score were obtained from the Dairy Herd Improvement Association. A lower limit of 50 d for days open was applied, and cows with more than 250 d open had days open set to 250 d. Independent variables for statistical analysis were the fixed effects of herd, parity, β-casein genotype (A1A1, A1A2, A2A2), and β-casein genotype by parity interaction. Cow nested within parity was the random effect in the statistical models for fertility and production traits. Herd had a significant effect on all fertility, production, and survival variables. Parity affected the number of times bred per pregnancy and days open, milk, fat, and protein production, and somatic cell score. Beta-casein genotype and herd influenced the percentage of cows surviving to first and second lactation. Results indicate no difference in production and fertility regarding β-casein genotype for organic dairy herds. Survival was biased against the A1 allele, which is indicated by lower survival rates during first lactation. These results may offer organic producers more flexibility in breeding and culling decisions to produce A2A2 milk.

Effects of Parity and Postpartum Depression on Mother-Infant Bonding in the First Month Postpartum: A Retrospective Study.

Objective This study aimed to examine the relationship between parity, postpartum depression (PPD), and mother-infant bonding (MIB) failure in the first month postpartum. Methods The study included 1,509 Japanese patients (748 primiparous and 761 multiparous). MIB was assessed using the Mother-to-Infant Bonding Scale Japanese version (MIBS-J), which was translated in 2012, and its subscales, including lack of affection (LA) and anger and rejection (AR). Postpartum depression (PPD) was assessed using the Japanese version of the Edinburgh Postnatal Depression Scale (EPDS) and its subscales, including anxiety (ANX), anhedonia (ANH), and depression (DEP). Multiple regression analyses using interaction terms were performed to examine the association of parity with the MIBS-J and EPDS. Results Parity was significantly associated with AR. ANX and ANH were strongly associated with LA, and ANX and DEP were strongly associated with AR. The interaction term "parity×EPDS total" was significantly associated with MIBS-J total, LA, and AR scores. Conclusions Primiparas and mothers with high ANX had more negative emotions toward their children during the first month postpartum, and mothers with high ANX or ANH had less interest in their children.

Exploring the association of parity and its interaction with history of preterm delivery on gestational duration

PurposePreterm delivery is a major cause of child mortality. While the relationship between parity and preterm delivery is known, its association with gestational duration and variability remains underexplored. Differences in variance may suggest interaction with other well-established risk factors. MethodsWith 1.1 million spontaneous deliveries (1990–2012) from the Swedish Medical Birth Register, we assessed while accounting for potential confounders the effects of parity on the mean and variance of gestational duration, and its possible interactions with history of preterm delivery. Pedigrees allowed to account for nonobserved, shared confounders using linear mixed models. ResultsParity has a modest association with mean gestational duration, but a large effect on its variance. For example, the first pregnancy had the shortest mean gestational duration, 0.29 days shorter (95% CI: −0.33, −0.25) than the second, and the largest variance (σ2 = 135 days2). Accounting for shared unobserved confounders highlighted a group effect bias, likely linked to the mothers’ total number of offspring. Parity interacts with other risk factors, including previous preterm delivery where the magnitude of its effect increases with parity (up to 4.6 days effect difference). ConclusionsNonshared factors across a mother's pregnancies highlight parity's importance to gain insight into the mechanisms governing the timing of delivery.