Prevalence, causes, resolution and consequences of bovine dystocia in Italy

Potential for automatic detection of calving in beef cows grazing on rangelands from Global Navigate Satellite System collar data

Dystocia is one of the main causes of calf death around calving. In addition, peripartum deaths may occur due to other factors, such as weather or predators, especially in the case of grazing animals. Precision Livestock Farming (PLF) tools aimed at the automatic detection of calving may be useful for farmers, allowing cow assistance in case of dystocia or checking the condition of the cow-calf pair after calving. Such PLF systems are commercially available for dairy cows, but these tools are not suitable for rangelands, mainly due to power and connectivity constraints. Thus, since most commercial PLF tools for rangelands are based on Global Navigate Satellite System (GNSS) technology, the objective of this study was to design and evaluate several indicators built from data gathered with GNSS collars to characterise their potential for the detection of calving on rangelands. Location data from 57 cows, 42 of which calved during the study, were curated and analysed following a standardised procedure. Several indicators were calculated using two different strategies. The first approach consisted of having indicators that could be computed using the data of a single GNSS collar (cow indicators). The second strategy involved the use of data from several animals (herd indicators), which requires more animals to be monitored, but may allow the characterisation of social behaviour. Several indicators, such as the length of the daily trajectory or the sinuosity of cow path, showed significant differences between the pre- and postpartum periods, but no clear differences between calving day and previous days. Herd indicators, such as the distance to herd centroid or to the nearest peer were superior in terms of the detection of calving day, as cows showed isolation behaviour from 24 hours before calving. Relative indicators, i.e., the value of cow or herd indicators for the calving cow in relation to the average value of the same indicators for its herdmates, provided additional information on cow behaviour. For instance, according to the relative indicator for the change in daily trajectory, pregnant cows had a differential exploratory behaviour up to 14 days before calving. In conclusion, data from commercial GNSS collars proved to be useful for the computation of several indicators related to the occurrence of calving on rangelands. Some of those indicators showed changes from baseline values on the day before calving, which could serve to predict the onset of parturition.

Association between dam and calf measurements with overall and fetopelvic dystocia in Holstein heifers

We investigated the relationship between dam's pelvic and calf's dimensions with dystocia due to fetopelvic disproportion in the Holstein breed and estimated risk factors and dystocia probability. For this purpose, external pelvic measurements were performed in 402 heifers 15 ± 11 (1-38) days ante-partum and specific conformation measurements were obtained from their calves 1.7 ± 1.2 post-partum. Dystocia was defined as the inability of the heifer to complete parturition spontaneously within 120 min after the appearance of the amnion with normal presentation, position and posture or as having definite obstetrical obstacles within 60 min. Overall and fetopelvic disproportion dystocia incidence was 10.4% and 5.2%, respectively. Heifer measurements mainly influenced overall dystocia, whereas calf conformation was related solely with fetopelvic dystocia. Specifically, heifers with a small pelvis (hip width <49.95 cm, pelvic inlet area <333.2 cm2, pelvic volume <7799.2 cm3) had 2.8 to 3.5 times greater incidence of overall dystocia (19.0-20.8%) compared to heifers with a larger pelvis (incidence of 7.0-7.6%). Regarding calf factors, sex (male calves), body weight, chest circumference and fetlock joint circumference significantly increased the odds of experiencing dystocia due to fetopelvic disproportion compared with female, lighter or smaller calves. In a backward elimination model with independent variables treated as continuous, an area under the ROC curve of 0.66 regarding the prediction of overall dystocia based on heifer pelvic length, and of 0.64 for the prediction of fetopelvic dystocia based on fetlock joint circumference was found. The combination of the two variables in one model improved the ROC area to 0.71 regarding dystocia due to fetopelvic disproportion, reaching acceptable level of discrimination. Our findings indicate that dystocia due to fetopelvic disproportion in heifers is mainly influenced by the fetal side. Additionally, the estimation of pelvic dimensions of the dam before parturition and specific conformation characteristics of the calf during parturition, especially fetlock joint circumference, could aid obstetricians and herdsmen regarding dystocia probability and parturition surveillance.

Retrospective analysis of 302 ovine dystocia cases presented to a veterinary hospital with particular attention to uterine torsion

Background

Dystocia is common in sheep, and foetal causes are predominant. Among maternal causes, insufficient cervical dilatation is the most frequent problem. Uterine torsion has been considered rare by many authors.

Objectives

This study was conducted to investigate causes of dystocia in sheep presented for veterinary attention, and particular focus was set on the description of uterine torsion and analysis of potentially predisposing factors for this condition.

Methods

Clinical records of 302 sheep treated for dystocia were evaluated retrospectively. Known and proposed risk factors for uterine torsion in cattle were analysed regarding their potential importance in sheep. These included lamb birth weights, ewe age, parity, season, nutrition, breed type, litter size and husbandry.

Results

Maternal causes of dystocia accounted for 67.2% (203/302) of the presented cases. Of these, insufficient cervical dilatation (121/203, 59.6%) was the most frequent diagnosis. Another substantial proportion of maternal causes (60/203, 29.6%) was identified as uterine torsion. Husbandry, breed type and litter size showed significance in univariate analyses, with lower odds for meat breeds (OR 0.22; p < 0.001), twin‐ (OR 0.49; p = 0.020) or multiple‐bearing ewes (OR 0.19; p = 0.013) and higher odds for fully housed animals (OR 17.87; p < 0.001). Year‐round housing was identified as the most influential factor in a subsequent multivariate analysis.

Conclusions

Uterine torsion was identified as a relevant cause of dystocia in our case load. The condition is likely to be underdiagnosed in sheep, and increased farmer and veterinary awareness is necessary to ensure adequate treatment of affected animals and to prevent unnecessary suffering.

Identification of cow-level risk factors and associations of selected blood macro-minerals at parturition with dystocia and stillbirth in Holstein dairy cows

A deeper understanding of the risk factors for dystocia and stillbirth could help farmers make decisions about dairy cow management. The objectives of this study were to investigate cow-level risk factors associated with dystocia and stillbirth in a relatively large sample of dairy cows using multivariable linear regression models. The data consisted of 51,405 calving records of 14,546 Holstein cows from 3 dairy herds in Isfahan Province, Iran, collected between April 2011 and September 2017. To investigate the association between selected blood macro-minerals and the incidence of dystocia and stillbirth, blood samples were collected at the time of parturition from a random subset of these cows, which included 1311 animals. The incidence of dystocia and stillbirths averaged 14.7% and 4.3%, respectively. Results showed that calving year, calving season, dry period length, BCS, parity, calf sex, calf birth weight, twin status, and stillbirth were significantly associated with the incidence of dystocia. According to the Random Forest (RF) classifier, we found that dry period length, calf birth weight, and parity were the most important cow-level risk factors for the incidence of dystocia. Calving year, calving season, parity, twin status, dry period length, calf birth weight, calf sex, and dystocia were significantly associated with the incidence of stillbirths. The most important risk factors identified by the RF classifier for stillbirths were twin status, parity, dry period length, and calf birth weight. Also, interactions between the cow-level risk factors associated with dystocia and stillbirth were identified. The incidence of dystocia was associated with the interactions of twin status × calf birth weight and twin status × stillbirth. According to our analysis, the incidence of stillbirth is caused by interactions among several factors, such as twin status × length of dry period, twin status × calving season, and twin status × parity. The highest incidence of dystocia (21.3%) and stillbirths (5.4%) was observed in hypo-calcemic cows. In conclusion, twin status seems to be a determining factor for the incidence of stillbirths but not for dystocia. Finally, the results of this study may help the dairy industry make management decisions aimed at reducing dystocia and stillbirth rates.

Calving Ease Risk Factors and Subsequent Survival, Fertility and Milk Production in Italian Holstein Cows

Simple Summary

Several studies have analyzed the potential risk factors for assisted calvings and the consequences of calving ease on cow performances. The present study used national data to focus on Italian Holstein cow herds. In summary, herd, number of calvings/herd/year, cow parity, gestation length, twinning, calf sex, previous calving-to-conception interval, dry period and close-up length, and calving season were identified as risk factors associated with calving ease. Regarding lactation performance, cows with assisted calving had higher 30 days in milk (DIM) culling risk, lower 150 DIM pregnancy risk and lower milk yield, measured as 60-d cumulative and as 305-d predicted milk yield. These results may be beneficial to focus attention on control, management and specific factors associated with calving ease in Italian Holstein herds and also to support adequate training and education of the personnel.

Abstract

The objectives of this study were to investigate the main risk factors associated with calving ease (CE) in Italian Holstein cow herds, and to estimate the association between CE and subsequent survival, fertility and milk production. Data obtained from Holstein cows in 40 Italian herds were retrospectively investigated. Calvings were surveilled and classified into two categories of CE, unassisted calving or assisted calving, based on the need for intervention. The following factors were analyzed as possible risk factor affecting CE: herd, number of calvings/herd/year, age at first calving (AFC), cow parity, gestation length, twinning, calf sex, previous calving-to-conception interval, previous milk yield, dry period and close-up length, and season of calving. The association between CE and culling risk within the first 30 days-in-milk (DIM), cumulative 60-d milk yield and predicted 305-d milk yield, and pregnancy risk within 150 DIM were also investigated. Of the 47,672 calvings, 37,892 (79.5%) were unassisted, while 9780 (20.5%) required some type of assistance. Among the risk factors, only the AFC was not correlated with CE, while for all the other risk factors an association with CE was detected. Assisted calvings were associated with an increased culling risk at 30 DIM, decreased 60-d milk yield, decreased 305-d milk yield and reduced pregnancy risk at 150 DIM. In conclusion, dairy herd management should aim at correcting/reducing the risk factors in order to limit the incidence of assisted calving, and possibly improve the quality of calving assistance; controlling CE within the herd is crucial to reducing culling risk, and achieving higher lactation and reproductive performance.

How to Predict Parturition in Cattle? A Literature Review of Automatic Devices and Technologies for Remote Monitoring and Calving Prediction

Cattle farming is facing an increase in number of animals that farmers must care for, together with decreasing time for observation of the single animal. Remote monitoring systems are needed in order to optimize workload and animal welfare. Where the presence of personnel is constant, for example in dairy farms with great number of lactating cows or with three milking/day, calving monitoring systems which send alerts during the prodromal stage of labor (stage I) could be beneficial. On the contrary, where the presence of farm personnel is not guaranteed, for example in smaller farms, systems which alert at the beginning of labor (stage II) could be preferred. In this case, time spent observing periparturient animals is reduced. The reliability of each calving alarm should also be considered: automatic sensors for body temperature and activity are characterized by a time interval of 6-12 h between the alarm and calving. Promising results have been shown by devices which could be placed within the vaginal canal, thus identifying the beginning of fetal expulsion and optimizing the timing of calving assistance. However, some cases of non-optimal local tolerability and cow welfare issues are reported. Future research should be aimed to improve Sensitivity (Se), Specificity (Sp) and Positive Predictive Value (PPV) of calving alert devices in order to decrease the number of false positive alarms and focusing on easy-to-apply, re-usable and well tolerated products.

Assessment of Sensitivity and Profitability of an Intravaginal Sensor for Remote Calving Prediction in Dairy Cattle

One critical point of dairy farm management is calving and neonatal first care. Timely calving assistance is associated with the reduction of calf mortality and postpartum uterine disease, and with improved fertility in dairy cattle. This study aimed to evaluate the performance and profitability of an intravaginal sensor for the prediction of stage II of labor in dairy farms, thus allowing proper calving assistance. Seventy-three late-gestating Italian Holstein cows were submitted to the insertion of an intravaginal device, equipped with light and temperature sensors, connected with a Central Unit for the commutation of a radio-signal into a cell phone alert. The remote calving alarm correctly identified the beginning of the expulsive phase of labor in 86.3% of the monitored cows. The mean interval from alarm to complete expulsion of the fetus was 71.56 ± 52.98 min, with a greater range in cows with dystocia (p = 0.012). The sensor worked correctly in both cold and warm weather conditions, and during day- or night-time. The intravaginal probe was well tolerated, as any cow showed lesions to the vaginal mucosa after calving. Using sex-sorted semen in heifers and beef bull semen in cows at their last lactation, the economic estimation performed through PrecisionTree™ software led to an income improvement of 119 € and 123 €/monitored delivery in primiparous and pluriparous cows, respectively. Remote calving alarm devices are key components of "precision farming" management and proven to improve animal welfare, to reduce calf losses and to increase farm incomes.

Incidence, clinical patterns, and risk factors of postpartum uterine diseases in dairy cows from high-altitude tropical herds

The cow's uterus sustains bacterial contamination and active inflammation after calving as part of the normal physiological process of uterine involution. Although the definition, incidence, and risk factors for postpartum uterine diseases (PUD) have been documented in annual calving systems with high-producing cows on total mixed ration, the literature contains little information for other production systems. The objective of this study was to quantify the incidence risk and factors associated with metritis, clinical endometritis, and cytological endometritis in high-altitude tropical dairy herds in a pasture-based system. A total of 248 cows from 5 commercial dairy herds in northern Antioquia, Colombia, were enrolled in this prospective observational longitudinal cohort study. Data collection and PUD diagnosis were performed at d 0, 3, 10, 17, 24, 31, 38, 45, and 52 (±1) after parturition. Between 60 and 70 d, cows were systematically enrolled in a synchronization protocol, and herds were visited monthly for pregnancy diagnosis until 180 ±15 d. The multivariable logistic regression model of variables associated with PUD occurrence included (a) parity, season of calving, transition diet, and body condition score at calving; (b) blood calcium, phosphorus, and magnesium concentrations, and milk urea nitrogen, β-hydroxybutyrate and fat-to-protein ratio; and (c) dystocia, retained placenta, and delayed uterine involution. The incidences of puerperal metritis, clinical metritis (MET), clinical endometritis (CE), and cytological endometritis (CYTO) were 2.8, 25, 29, and 26%, respectively. Retained placenta and dystocia were associated with MET, and MET was associated with CE. Low blood calcium concentration at calving was associated with CYTO. Overall, 51.2% of the cows suffered at least 1 category of PUD during the first 60 d postpartum (DPP). However, cows also suffered from different consecutive clinical events of PUD (MET, CE, and CYTO) during the follow-up period (0 to 180 ±15 DPP). These events could be grouped into 4 types (which were referred to as "clinical patterns") based on interactions between MET, CE, and CYTO.

Genetic relationships of calving difficulty with birth measurements and carcass traits in Japanese Black cattle

The objectives of this study were to compare the genetic parameters for calving difficulty (CD), which were treated as both a calf trait (CD_calf) and as a dam trait (CD_dam), and to clarify genetic relationships of these CDs with body size traits of calves at birth and carcass traits. In total, the CD records and calf body measurements of 2,258 Japanese Black cattle heifers were used in this study, in addition to the carcass records of 4,300 feedlot steers and heifers. Direct heritability of CD_calf (0.44) was higher than maternal heritability of CD_calf (0.30), as well as CD_dam heritability (0.25). Direct genetic correlations between CD_calf and calf body size were moderate to strongly positive (0.64 to 0.81). The correlations between EBVs of CDs and carcass weight were also positive (0.30 to 0.64). These positive relationships showed that genetically improving CD (reducing dystocia) could produce smaller calves and carcasses. In contrast, the correlations between CDs and beef marbling score were weak, suggesting that improving CD would not influence meat quality traits. Fitting an animal model to CD_calf could be more preferred to fitting the model to CD_dam, because the former could separate the genetic effects of dams and calves.

Predicting the start of calving in Japanese Black cattle using camera image analysis

This study assessed the feasibility of using camera image analysis to detect behavioral changes as an indicator of the onset of calving in Japanese Black cattle. Thirty-five pregnant cattle individually housed in pens were used and were continuously monitored using a digital camera system. For the automatic determination of the x and y coordinates of a cow, trajectory analysis was conducted using thermal image and analysis software, and the distances moved were calculated using coordinate data. Further, the frequency of postural changes and the time spent tail raising per hour were measured for 14 cows using visible images. The measurement data were used to calculate hourly data for 12 h prior to amniorrhexis (first rupture of the allantoic sac). The hourly distances moved tended to increase at the time of amniorrhexis, with significantly longer distances measured 3–0 h before amniorrhexis than those at 12–8 h before amniorrhexis (P < 0.05). In all cows, amniorrhexis occurred within 11 h of hourly distances moved by more than 50% compared with distance moved the previous hour. The overall average elapsed time before amniorrhexis was 9 h 30 min (range: 5–11 h). Tail raising time and the frequency of postural changes significantly increased at 1–0 h and 2–0 h before amniorrhexis, respectively. This suggests that predicting the time of calving is possible by measuring the activity of Japanese Black cows during late pregnancy using camera image analysis as a non-invasive technique.

Prevalence, survival and subsequent fertility of dairy and beef cows with uterine prolapse

The aim of this study was to evaluate the prevalence of uterine prolapse in cows and assess its effects on survival and subsequent fertility. Of 33,450 calving cows considered retrospectively, 216 (0.6%) developed uterine prolapse. A higher prevalence was found in beef cows (n = 57/5,700 cows, 1%) compared to dairy cows (n = 157/27,750 cows, 0.6%). Treatment consisted of cleaning and replacing the uterus with local administration of antibiotics, and applying a harness for uterine containment. The recovery rate was 81.9% (n = 177), similar in dairy (n = 129; 81.1%) and beef (n = 48; 84.2%) cows. Of the 216 cows with uterine prolapse, 18 (8.3%) died before or immediately after treatment; 21 cows (9.7%) were voluntarily culled for economic reasons (low milk yield, low fertility, insufficient weight gain). All recovered dairy cows were artificially inseminated with semen of proven fertility after a voluntary waiting period of 50 days; the beef cows were naturally mated. Among the 172 inseminated/mated cows, 84.7% (n = 150) became pregnant (83.7% dairy cows, 87.5% beef cows), while 15.2% (n = 27) did not conceive. Recurrence of uterine prolapse at subsequent calvings was recorded in one dairy cow. Based upon the data presented here, treated cows with uterine prolapse showed high chances of survival and conception, and a low risk of recurrence.

Serum biochemistry in cows of different breeds presented with reproductive conditions

Minimising health problems and increasing yield have always been the objectives in livestock agriculture. Hence, increases in incidences of reproductive conditions in cattle farming pose a great threat to productivity and impose undesirable economic implications. This study aimed to examine the concentrations of different biochemical compounds in cows with reproductive conditions. Seventy-seven blood samples were collected from cows at different rural areas around Mafikeng, following cases of downer cow syndrome, dystocia, retained placenta, vaginal prolapse and abortion. Means of serum metabolites across the different reproductive conditions were statistically compared using Pearson's chi-square test to determine variations of serum metabolites in cows of different breeds. In mixed breed cows, higher than normal calcium concentrations were observed in downer cow syndrome (25.25 ± 8.47) and dystocia (85.50 ± 8.46) cases. It was also observed that cholesterol concentrations were significantly low in abortion (2.52 ± 0.79), retained placenta (3.18 ± 0.61) and vaginal prolapse (2.37 ± 0.97) cases in Afrikaner cows. The study showed that Brahman (43.1%) and Afrikaner (43.1%) breeds were mostly affected by downer cow syndrome. Additionally, the occurrences of downer cow syndrome (53.9%) and abortions (60%) were mostly observed in cows of 1-3 years, in second and first parities, respectively. This study proves that concentrations of calcium, urea or blood urea nitrogen (BUN), magnesium and cholesterol are significantly altered in incidences of reproductive conditions in cows of different breeds. It is also shown that serum biochemistry is affected by reproductive conditions in cows of different ages and parity. This data serves as a tool that could be used to enhance research in animal production and reproduction.