Retrospective analysis of factors associated with umbilical diseases in foals

In neonatal foals, umbilical remnants can be affected by infectious and non-infectious diseases. This study aimed to retrospectively evaluate historical, management and clinical factors that may be related to the occurrence of umbilical remnant diseases. Clinical reports of foals born or hospitalized within 24 h of life during the 2017-2021 foaling seasons were reviewed. Forty/183 foals (21.9 %) developed umbilical remnant diseases (URD group), while 143/183 foals (78.1 %) had normal umbilical remnants (NUR group). In the URD group, 24/40 (60 %) had a patent urachus, 16/40 (40 %) omphalo-arteritis, 4/40 (10 %) omphalo-phlebitis, 10/40 (25 %) urachitis, 9/40 (22.5 %) abscess, 3/40 (7.5 %) periumbilical hematoma and 12/40 (30 %) more than one condition. URD frequency was higher in foals hospitalized after birth than in those born at the hospital (17/46 vs 23/137; P = 0.0068), lower in those that had access to the paddock before three days of life (p = 0.0426) and higher in recumbent foals (P = 0.0001). URD occurred more frequently after dystocia (P = 0.0068), prolonged stage II parturition (19±20.51 min vs 13±6.41 in NUR group; P = 0.0279), traction at parturition (P = 0.0005), and in foals with lower APGAR scores (8±1.72 vs 9±0.86 in NUR; P = 0.0063). Sepsis (P = 0.0245), neonatal encephalopathy (P = 0.0014), meconium retention (P = 0.0241) and congenital flexural limb deformities (P = 0.0049) were the most common associated diseases. Umbilical cord (UC) coiling, abnormal UC rupture, umbilical hemorrhage and increased umbilical stump volume occurred more frequently in URD than in NUR group (P = 0.0329, P = 0.0191, P = 0.0007 and P < 0.00001, respectively). Recognition of the identified predisposing historical, management and clinical factors should prompt careful umbilical remnant monitoring in neonatal foals.

Analysis of histone H3K4me3 modifications in bovine placenta derived from different calf-production methods

In ruminants, the overgrowth of offspring produced by in vitro fertilization (IVF) is a common problem. Abnormal epigenetic modifications caused by environmental factors during the early embryonic period are suspected as an aetiology of overgrowth. In this study, we investigated the genome-wide histone H3K4me3 profiles of bovine placentae that play a pivotal role in foetal development and compared their characteristics between artificial insemination (AI)- and IVF-derived samples. Cotyledons were harvested from the placentae obtained at parturition of 5 AI- and 13 IVF-derived calves, and chromatin immunoprecipitation sequencing was performed for H3K4me3. We confirmed no significant maternal tissue contamination in the samples we used. The revealed H3K4me3 profiles reflected the general characteristics of the H3K4me3 modification, which is abundantly distributed in the promoter region of active genes. By extracting common modifications from multiple samples, the genes involved in placenta-specific biological processes could be enriched. Comparison with the H3K4me3 modifications of blastocyst samples was also effective for enriching the placenta-specific features. Principal component analysis suggested the presence of differential H3K4me3 modifications in AI- and IVF-derived samples. The genes contributing to the difference were related to the developmental biological processes. Imprinted genes such as BEGAIN, ZNF215 and DLX5 were among the extracted genes. Principal component and discriminant analyses using only male samples categorized the samples into three groups based on foetal weight and calf-production methods. To our knowledge, this is the first study to profile the genome-wide histone modifications of bovine foetal placentae and reveal their differential characteristics between different calf-production methods.

Evaluation of blood minerals and oxidative stress changing pattern in prepartum and postpartum Achai and Holstein Friesian dairy cows

This research focused on evaluating blood mineral levels and malondialdehyde (MDA) as an indicator of oxidative stress before and after giving birth in Achai and Holstein Friesian (HF) dairy cows. Blood samples were obtained from a total of 50 cows representing both breeds on the third, second, and first week prior to calving, as well as on the day of calving (day 0). Subsequently, samples were collected on the 1-3 weeks postpartum to allow a comprehensive evaluation of blood parameters throughout the peripartum period. Results showed a significant (p < .01) decrease in serum zinc (Zn) levels on the day of parturition in both breeds. Additionally, HF cows exhibited higher (p < .01) Zn levels on week 2 before giving birth. Interestingly, blood selenium (Se) concentration increased (p < .01) in HF cows on weeks 2 and 3 after calving. In contrast, Achai cows showed a rise (p < .01) in blood Se on week 3 of parturition. Blood copper (Cu) levels were higher (p < .01) on weeks 2 and 3 after parturition in HF cows and on third week before parturition compared to Achai cows, where serum Cu remained high on week 1 of parturition. The findings indicated that blood magnesium (Mg) was higher (p < .01) on third week before parturition in Achai cows and on weeks 2 and 3 after parturition. Serum calcium (Ca) was higher (p < .01) in both HF and Achai cows on weeks 2 and 3 after parturition, and lower (p < .01) on third week before giving birth in both breeds. The mean blood MDA levels in Achai cows were lower (p < .01) on weeks 1 to 3 postpartum or 3 weeks before giving birth. In HF cows, serum MDA increased (p < .01) just before 2 weeks of parturition and remained elevated until 3 weeks of parturition. Thus, both breeds exhibited a similar pattern of mineral fluctuations; yet, Achai cows demonstrated greater resilience to oxidative stress compared to HF cows during the transition period.

[Morbidity and mortality of mare and foal following dystocia - a literature review]

Dystocia represents a life-threatening condition for mare and foal. Morbidity and mortality rates due to a difficult birth, as well as the influence on fertility of the mare were analyzed, based on a review of publications. This was aggravated by the fact that no standardized diagnostic code was used and that most publications do not clearly describe how extensively the examinations were performed beforehand. Retentio secundinarum is the most common complication caused by dystocia. Other complications are injuries to the soft birth canal and the colon. These occur more frequently after surgical obstetrics than following assisted vaginal deliveries. Performing a fetotomy increases the risk of injury to the birth canal. After a caesarean section, the risk for retained placenta increases significantly. In order to evaluate the possibility of medical progress over time, mortality rates of mare and foal were investigated and divided in surgical and conservative obstetrics within the period of 1970-1990 and 1991-2021. The average maternal mortality rate following caesarean section amounted to 18% in the time period between 1970 and 1990 and 14% between the years from 1991-2021. After fetotomy, the two determined mortality rates amounted to 29% and 10% for the time between 1970 and 1990. In the period 1991-2021, the rate varies between 4% and 44% with an average mortality rate of 14%. Following controlled vaginal delivery, the average mortality rate is 9%. Literary sources were however only available for the current time period and range between 6% and 29%. The morbidity and mortality rate of foals is very high. Following caesarean section on average 53% of foals are dead on delivery, with a range of 13-79% in case reports from the years 1991-2021. The number of dead foals in the context of conservative obstetrics is of a similar scale. Postnatal foal diseases are largely due to intrapartum hypoxia during dystocia and obstetric injury. In consequence of a difficult delivery, mares experience reduced fertility. In numerous cases this however may be compensated by pausing from further breeding in the same year. The number of cases evaluated in this context however remains too small to advocate any recommendations for breeding following incidents of dystocia.

[Diagnostic Imaging during pregnancy of the dog]

Diagnostic imaging represents an important part during modern pregnancy management of the dog. Ultrasound has become the modality of choice for an early pregnancy diagnosis, enabling a verification as early as 17-20 days after LH surge. Furthermore an evaluation of fetal viability and development is possible as well as the depiction of malformations and an early assessment of fetal stress. Doppler imaging may also be of supporting value in this context . Using fetal maturity as well as measurements of fetal and extrafetal structures, a calculation of the gestational age and therefore the time of parturition is achievable. Radiographs of the caudal abdomen enable pregnancy diagnosis from the 43rd day after LH surge onward. In addition, an assessment of fetal size as well as litter size is possible. Both modalities allow for complementary statements concerning possible labor complications and possess supporting value concerning the decision of necessary obstetric intervention and further management in patients with dystocia.

Clinical and pathological findings for rabbits with dystocia: 10 cases (1996-2016)

OBJECTIVE

To characterize clinical and pathological findings of rabbits evaluated at a veterinary teaching hospital because of dystocia.

DESIGN

Retrospective case series.

ANIMALS

9 client-owned rabbits and 1 wild rabbit with signs of dystocia evaluated at a veterinary teaching hospital from 1996 through 2016.

PROCEDURES

Medical records of rabbits were reviewed to collect data on signalment; medical history; physical examination, laboratory, diagnostic imaging, and procedural findings; treatment; final diagnosis; and outcome. Data were summarized.

RESULTS

Dystocia in 7 rabbits was successfully managed through medical treatment, assisted vaginal delivery, or both (n = 6) or surgery alone (1); 3 rabbits were euthanized. Primiparous does, does ≤ 4 years old, and does of small breeds (< 2 kg [4.4 lb]) were most common. All client-owned rabbits had clinical signs of abnormal second-stage parturition, whereas the wild rabbit had only hemorrhagic vulvar discharge. Imaging was used to identify the number, size, and state of fetuses in most rabbits. Overall, 35 fetuses were accounted for, 25 of which were dead or later died. The cause of dystocia was determined for 8 rabbits and included fetal-maternal mismatch (n = 4), uterine inertia (2), fetal death or mummification (1), and stress-induced abortion (1).

CONCLUSIONS AND CLINICAL RELEVANCE

Obstructive dystocia from fetal macrosomia with or without secondary uterine inertia was the most common cause of dystocia in the evaluated rabbits. Although medical management was successful for many rabbits with dystocia in this study, surgery could still be required in other affected rabbits, particularly when fetal-maternal mismatch is involved.

Comparison of Foaling Prediction Technologies in Periparturient Standardbred Mares

The ability to predict impending foaling is invaluable, as attending foaling improves mare and foal outcome during parturition; therefore, a comparison of foaling prediction technologies is warranted. The purpose of this study was to compare technologies to predict foaling. Forty Standardbred mares were monitored daily for parturition. Prefoaling mammary secretion was collected daily and evaluated using a: calcium titration method (Ca titration), calcium and magnesium strip (Ca and Mg), handheld digital pH device (pH digital), pH strip, and refractometer (Brix). In addition, a birth monitoring system that was attached in the mare's vulva was studied and all positive alarms (foaling) and negative alarms (false alerts) were recorded. Analysis of variance, correlation, and logistic analysis were used to analyze the different technologies and their associations between parity and foal gender. Receiver operator characteristic analysis for cutoff value and subsequently sensitivity, specificity, positive, and negative predictive values for each technology were obtained. Maiden mares and mares carrying a colt had a longer gestational length. Multiparous and maiden mares had no difference in their prefoaling mammary secretion pH using the digital and pH strip technologies when predicting foaling; however, the calcium concentrations measured using the Ca titration technology were lower in multiparous than in maiden mares. The Ca titration technology was the single best technology to predict when the mare was not going to foal; and when the Ca titration and pH digital were used in combination, their prediction for foaling increased when compared with using each technology individually.

[Treatment of long bone fractures in 125 newborn calves. A retrospective study]

OBJECTIVES

Retrospective study of the causes, location, configuration, treatment and outcome of long bone fractures in newborn calves.

MATERIAL AND METHODS

The medical records of 125 calves presented during a 16-year period because of fracture of the humerus (3 calves), radius/ulna (14), femur (50) or tibia (58) were evaluated. The majority of calves (61.6%) sustained the fractures during assisted delivery. Of 125 calves, 107 were treated and 18 were euthanized because of concurrent diseases. Conservative treatment was used in 16 calves and surgical treatment in 91. Four of the latter were euthanized because of muscle contraction which prevented fracture reduction, and five others died in surgery.

RESULTS

Fracture healing occurred after conservative treatment in 10 of 16 calves and after surgical treatment in 44 of 82 calves. The outcome was better in calves with plate and clamp-rod internal fixation (37/58 healed) than with intramedullary pinning (4/16 healed) or external fixation (3/8 healed). There were significant associations (chi2-test, p<0.01) between concurrent diseases and choice of therapy and fracture healing. Of 67 calves that developed complications, only 26 could be cured. Common complications were implant loosening and instability, which were often followed by osteomyelitis and sepsis. Implants were removed in 39 of 44 surgically treated calves that survived up to 6 months postoperatively. Long-term follow up (> 6 months postoperatively) by clinical and radiographic re-examination (25 calves) or telephone inquiry (29 calves) revealed that 54 animals were sound and had returned to their intended use.

CONCLUSIONS AND CLINICAL RELEVANCE

The treatment of long bone fractures in newborn calves remains difficult because of a high incidence of complications. These are most likely attributable to trauma during delivery, which results in insufficient colostrum intake and predisposes to concurrent diseases. In addition, the characteristics of juvenile bones do not provide sufficient physical strength for implants. Therefore, professional and diligent assistance during forced extraction, particularly in presentations with "stifle lock" or "hip lock", is required to minimize the incidence of long bone fractures in newborn calves. Most cases require surgical fixation, which is time consuming, expensive and carries a guarded prognosis.

Retrospective study of dystocia in mares at a referral hospital

REASONS FOR PERFORMING STUDY

The period between the onset of dystocia and its resolution has an important bearing on fetal outcome. There are few published data on which to base decisions regarding optimum management of cases in practice.

OBJECTIVES

To evaluate and compare the effects of a coordinated dystocia management protocol (CDMP) with that of a previous protocol of random management on time to resolution and outcome in both an emergency dystocia referral population of mares (referred emergency cases: EM) and in a population of mares residing in hospital due to high risk pregnancy (HRP) concerns that then experience dystocia at parturition.

METHODS

Retrospective study performed at a university hospital referral centre of cases presenting from 1991-2004 divided into Group 1 (pre-CDMP) and Group 2 (CDMP).

RESULTS

Medical records of 71 cases with dystocia were retrieved and data recorded. For referred emergency cases (EM), time from hospital presentation to resolution decreased significantly by 32 min (P = 0.03) after institution of CDMP. Survival rate of mares at discharge was 86%. Survival of EM foals was low, with 10% in Group 1 and 13% in Group 2, surviving to discharge. For EM foals delivered alive, survival to discharge was 30% and 43% in Groups 1 and 2, respectively. Median Stage II was significantly (P < 0.001) different at 71 and 282 min for EM foals delivered alive vs. those not alive at delivery, respectively. Median duration of Stage II was also significantly (P < 0.001) different between EM foals surviving and not surviving to discharge, at 44 and 249 min, respectively. Survival of HRP dystocia foals to discharge was 79%.

CONCLUSIONS

Although CDMP reduced the time from presentation at the hospital to resolution significantly for EM, total duration of Stage II for EM was unchanged, as was foal outcome.

POTENTIAL RELEVANCE

Very early referral of mares with dystocia to referral centres with dystocia management protocols may improve fetal outcome as increased duration of Stage II in the horse affects fetal outcome negatively.

Survival rate and short-term fertility rate associated with the use of fetotomy for resolution of dystocia in mares: 72 cases (1991–2005)

OBJECTIVE

To determine survival rate, complications, and short-term fertility rate after fetotomy in mares.

DESIGN

Retrospective study.

ANIMALS

72 mares with severe dystocia.

PROCEDURES

Records from 1991 to 2005 were searched for mares with dystocia in which a fetotomy was performed. Data relating to presentation and position of foals; survival rate, complications, and short-term fertility rate in mares; and 45-day pregnancy rate in mares bred 2 to 3 months after fetotomy were recorded.

RESULTS

Anterior fetal presentation was detected for 54 of 72 (75%) mares, posterior presentation was detected for 13 (18.1%), and transverse presentation was detected for 5 (6.9%). One fetus in anterior presentation was hydrocephalic. Survival rate after fetotomy was 95.8%. Complications included retained fetal membranes (5.5%), laminitis (6.9%), vaginal and cervical lacerations (2.8%), and delayed uterine involution (2.8%). Mares bred 2 to 3 months after fetotomy had good short-term fertility, with a mean pregnancy rate of 79.4% at 45 days after breeding.

CONCLUSIONS AND CLINICAL RELEVANCE

The survival rate was high, compared with rates reported after cesarean section, and short-term fertility rate was similar to those reported for mares that had a controlled vaginal delivery or cesarean section. Fetotomy performed by a skilled veterinarian on a nonviable fetus should be considered as a means of quick and safe correction of dystocia that does not necessarily impair short-term fertility in affected mares.

Serum protein pattern during cow pregnancy: Acute-phase proteins increase in the peripartum period

Serum collected in a time-course mode during the pregnancy of a group of heifers was analyzed by 2-DE under various experimental conditions to optimize resolution of all protein spots. Changes in the levels of some components were detected during the last phase of pregnancy and early postpartum. These included a decrease of alpha2-HS-glycoprotein, an increase of alpha1-antichymotrypsin and, with a much larger and more abrupt variation, of orosomucoid and haptoglobin. These findings associate the weeks preceding calving with an acute-phase reaction. Analysis of individual animal's sera by 1-DE demonstrated a higher level of orosomucoid in the sera of cows developing postpartum endometritis during the 2 wk after calving (i.e., in the course of the infection) but a lower level during the 2 wk before calving. This observation could represent an important tool for the prepartum detection of animals prone to develop postpartum endometritis and lead to a more accurate peripartum management of those animals.

The management and welfare of some common ovine obstetrical problems in the United Kingdom

This review approaches sheep welfare during the periparturient period from a veterinary practitioner viewpoint. At the most fundamental husbandry level, the general hygiene standards adopted on many sheep farms in the United Kingdom (UK) during the lambing period are unacceptable and require urgent improvement. Concerns also arise from obstetrical conditions attended by farmers which cause pain that can be identified using clinical criteria such as altered demeanour and behaviour of the ewe, and the presence of inflammation of the reproductive tract. Reduced production is evidenced by poor milk production and hungry lambs, the necessity to rear such lambs artificially and, in neglected cases, death of the ewe and her lambs. The correction of dystocia, periparturient vaginal, uterine and rectal prolapses is greatly facilitated after epidural injection of lignocaine, or a combination of xylazine and lignocaine administered by a veterinary surgeon. However, the perceived high professional fees charged for these services, and for Caesarean operations, result in few sheep receiving veterinary care, with such neglect directly contributing to poor welfare standards and an increased ewe mortality rate during the periparturient period. Whilst ending any welfare concern, the destruction of ewes rather than requesting veterinary services purely for economic reasons is a disturbing trend in sheep production in the UK and raises concerns regarding positive interaction between veterinary practitioner and farmer. In this article, veterinary treatments which provide effective analgesia are described and costed for obstetrical conditions in sheep. Recommended treatment protocols are described for the common obstetrical problems in sheep. In addition to appropriate treatment of obstetrical problems and alleviation of pain, if veterinary involvement could reduce ewe periparturient mortality from estimated figures of 4-2% this would save an estimated 400,000 ewes annually in the UK. Sheep welfare could be considerably improved by practising veterinarians providing practical instruction to small groups of clients with funding provided by government agencies.

Calving and calving management of beef cows and heifers on cow-calf operations in the United States

A national sample of cow-calf producers was contacted to participate in a study to describe selected calving management practices on operations throughout the United States. Information was gathered on calving season, frequency of dystocia, frequency of observation, timing of assistance, and calving facilities. Regional and herd size differences existed in all parameters evaluated. Most calves (63.9%) were born in the months of February, March, and April. Overall, 16.7% of heifers and 2.7% of cows required some level of assistance in calving. Heifers and cows were checked an average of only 3.6 and 2.5 times per 24 h period during the calving season. Producers allowed heifers to labor for an average of 2.8h prior to lending assistance in calving while cows were allowed an average of 3.5h before providing assistance. In addition, only 39.6% of calvings took place in specialized calving areas presumably to allow increased observation frequency, timely intervention and protection from the elements. Collectively, these management practices illustrate that opportunities exist to improve calf survivability and increase reproductive efficiency in many cow herds.

Prediction from ultrasonographic measurements of the expected delivery date in two species of bottlenosed dolphin (Tursiops truncatus and Tursiops aduncus)

Ultrasonographic measurements were made at least once a month during 14 gestations in seven Tursiops truncatus and 12 gestations in five Tursiops aduncus (bottlenosed dolphins). The 121 measurements of the fetal biparietal diameter and 139 measurements of the fetal thoracic diameter in T truncatus and the 97 measurements of the biparietal diameter and 97 measurements of the thoracic diameter in Taduncus were used to establish regression lines for the increases in the diameter of the head and thorax of the fetus with time. From these relationships an easy-to-use computer program was developed to predict the date of birth of the two species of bottlenosed dolphin, and its predictions were compared with the actual dates of birth of other calves of both species. The births occurred within the range of predicted dates, and even when only a few measurements were available, the program provided accurate predictions.

Outcome and subsequent fertility of sheep and goats undergoing cesarean section because of dystocia: 110 cases (1981-2001)

OBJECTIVE

To determine the outcome and subsequent fertility of sheep and goats undergoing a cesarean section because of dystocia.

DESIGN

Retrospective study.

ANIMALS

85 sheep and 25 goats.

PROCEDURE

Medical records were reviewed, and information was obtained on signalment, history, physical examination findings, anesthesia protocol, surgical technique, number of lambs or kids delivered, pre- and postoperative treatments, duration of hospitalization, and postoperative complications. Follow-up information was obtained through telephone conversations with owners.

RESULTS

The proportion of sheep admitted to the veterinary teaching hospital during the study period that underwent a cesarean section (4.4%) was significantly higher than the proportion of goats that did (2.2%). Pygmy goats were overrepresented, compared with the hospital population. The most common reason for cesarean section was inadequate dilatation of the cervix. The most common surgical approach was via the left paralumbar fossa. Two hundred one lambs and kids were delivered, of which 116 were dead at delivery or died shortly afterward. Forty-two of the 65 dams with 1 or more dead fetuses had been in stage-2 labor for > 6 hours, and fetal death was significantly associated with a prolonged duration of dystocia. The most common complication following surgery was retained placenta (n = 49). Use of antimicrobials was associated with a lower rate of complications. All 16 dams that were rebred became pregnant and had no problems with dystocia.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that cesarean section is an effective method of resolving dystocia in sheep and goats and does not adversely affect subsequent fertility.

Poly(ADP-ribose) polymerase in bovine retained and not retained placenta

Poly(ADP-ribose) polymerase (PARP) synthesizes poly(ADP-ribose) in response to DNA strand breaks using NAD+ as a substrate. It leads to consequences for metabolism not only on a cellular level, but also on a tissue level, among others: NAD+ and ATP depletion. Retention of foetal membranes (RF) in cows is supposed to be connected with the imbalance between production and neutralization of reactive oxygen species, leading to oxidative damage to DNA, lipids and proteins. The aim of this preliminary study was to detect the presence of PARP in bovine placenta and to describe the enzyme with respect to type of placental tissue, time and mode of delivery. Placentomes, collected after spontaneous delivery or caesarian section, were divided into maternal and foetal parts of placenta, homogenized, and subjected to electrophoresis. Cows were divided into six groups as follows: (A) caesarian section before term with RF, (B) caesarian section before term without RF, (C) spontaneous delivery at term with RF, (D) spontaneous delivery at term without RF, (E) caesarian section at term with RF, (F) caesarian section at term without RF. PARP was detected by Western blotting using commercially available bovine anti PARP antibody. Bands referred to as bovine PARP standard were present in all examined tissues as well as the products of its cleavage. However, the patterns of bands were different with respect to type of tissue, time, and mode of delivery. Further experiments on detailed relationship between PARP activity and the process of releasing and retaining of bovine placenta are necessary.

Dystocia in a referral hospital setting: approach and results

REASONS FOR PERFORMING STUDY

Dystocia in the mare is an emergency in which duration has a profound effect on survival of the foal. Specific examination of the effects of dystocia duration on foal survival provides information to enable horse care personnel and veterinarians to manage these cases more effectively and maximise the chances of obtaining a live foal.

HYPOTHESIS

Dystocia duration would have a negative impact on foal survival while method of dystocia resolution would not have an effect on foal survival. Additionally, we were interested in determining the effects of dystocia on subsequent fertility.

METHODS AND RESULTS

In the years 1986-1999, 247 dystocias were admitted. Of these, 91 % resulted in survival and discharge of the mare, 42% in delivery of a live foal, and 29% of foals survived to discharge. Period from hospital arrival to delivery for foals alive at discharge (23.0 +/- 14.1 mins) was not significantly different than for foals not surviving (24.8 +/- 10.6 mins) (P > 0.05); and from chorioallantoic rupture to delivery for foals alive at discharge (71.7 +/- 343 mins) was significantly less than for foals not surviving (853 +/- 37.4 mins) (P < 0.05). Average predystocia live foaling rates for all mares with available records was 84%. Overall post dystocia live foaling rates over the entire period of this study were 67%. Of mares bred in the year of the dystocia, 59% had a live foal in the year following.

CONCLUSIONS

Based on these results, dystocia duration has a significant effect on foal survival and resolution methods should be chosen to minimise this time, as the difference between mean dystocia duration for foals that lived and those that did not in this study was 13.6 mins. Post dystocia foaling rates reported here are higher than previously reported for both same-season and overall breedings, indicating same-season breeding may be rewarding for select dystocia cases.

POTENTIAL RELEVANCE

Dystocia resolution methods that minimise delivery time may maximise foal survival. Post dystoicia breeding may be rewarding in select cases.

[Investigations about kind and frequency of mechanical dystocia in ewes with special regard to the vaginal prolapse ante partum]

The incidence of dystocia from ewes in nine lambing periods (1992-2000) was recorded at an obstetrical clinic. First we analysed parturition difficulties in normal pregnant sheep (group 1, n = 229). In the second group parturitions of ewes with vaginal prolapse ante partum were investigated (n = 129). In group 1 maternal causes of dystocia occurred more often than fetal ones (50% maternal, 45% fetal). In maternal parturition difficulties ringwomb was the dominating reason (64%), while abnormal presentations, position and/or posture of the lambs occurred most frequently in fetal dystocia (67%). But there was no statistical influence of age and number of parturitions in both groups. The average of the first notice of prolapsed vaginal tissue was 11 days before lambing. There was a predominance in the affection of sheep at first and second pregnancy (52%). Only 26% of the group 2 sheep had a spontaneous delivery. In 58% of the cases a dystocia was diagnosed. A preterm caesarean section had carried out in 12%, five ewes died before parturition because of septicemia (4%). Sheep suffering from vaginal prolapse ante partum showed maternal caused dystocia significant more frequently than members of group 1 (p < 0.001), with ringwomb as dominating reason (70%). The number of born lambs was significant higher in group 2 than in group 1 (p = 0.019).

Spontaneous oxidative DNA damage in bovine retained and nonretained placental membranes

Retention of fetal membranes (RFM) is believed to be associated with conditions of oxidative stress. In this study, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) was used for the determination of spontaneous oxidative DNA lesions in maternal and fetal parts of bovine retained and nonretained placentas. Placental specimens were collected directly after spontaneous delivery or during cesarean section from cows divided into 6 groups: (A) cesarean section before term without RFM, (B) with RFM, (C) cesarean section at term without RFM, (D) with RFM, (E) spontaneous delivery at term without RFM and (F) with RFM. Isolated DNA was hydrolyzed and analyzed by HPLC; native nucleosides were monitored at 254 nm and 8-OH-dG by electrochemical detection. No significant differences in 8-OH-dG levels between retained and nonretained placental tissues were found in all samples from preterm groups (mean concentrations between 13 and 42 micromol/mol deoxyguanosine (dG)). In the term cesarean section group with RFM a significant increase in 8-OH-dG concentration in DNA from maternal (8-fold) and fetal (18-fold) membranes were detected when compared to the respective nonretained tissues. Also, in the term spontaneous delivery groups maternal nonretained placental tissues showed increased levels of 8-OH-dG in comparison to the respective tissues of the retained placenta group. In placental tissues oxidative DNA lesions appear to be controlled by responsive mechanisms which, possibly following exhaustion, give rise to increased 8-OH-dG levels.

Reproductive performance of Friesian mares after retained placenta and manual removal of the placenta

Because the incidence of retained placenta in Friesian mares is estimated to be high, and no reports have been published on the reproductive performance of Friesian mares after retained placenta, we studied postpartum reproductive performance in Friesian brood mares with (n = 54) and without (n = 50) retained placenta. We defined a retained placenta as the failure to expel all fetal membranes within 3 h after the delivery of a foal. We subdivided the group of mares with retained placenta into mares in which the placenta had been removed manually (n = 30) and mares in which it had not (n = 24). Within each group, we compared reproductive performance after breeding in the foal heat and breeding in a subsequent heat. We also recorded the age of the mares, number of mares treated with antibiotics after insemination, and number of mares treated with prostaglandins. The interval between delivery and conception, efficacy rate (number of served cycles divided by the number of mares that had a positive pregnancy diagnosis), seasonal pregnancy rate, pregnancy rate after first insemination, pregnancy loss rate, and foaling rate did not differ between mares with and without retained placenta or between mares with and without manual removal of the retained placenta. Within each group, the pregnancy rate after first insemination did not differ between breeding for the first time in the foal heat and breeding for the first time in a subsequent heat. We concluded that reproductive performance did not differ between (1) Friesian mares with and without retained placenta and (2) Friesian mares with and without manual removal of the placenta. With regard to reproductive performance, retained placenta and manual removal of the placenta are not valid reasons to avoid foal heat breeding in Friesian mares.

Management of calving in Norwegian cubicle-housed dairy herds

Sixty of the 65 dairy farms with cubicle houses in the Norwegian county of Oppland were included in a field study of the management of calving in 1990. The farmers recorded the location of the cow when giving birth, farmer presence and whether assistance was given during calving, occurrence of suckling, and time after birth when cow and calf were separated. Such data were recorded for a total of 1125 calvings. About 10% occurred on pasture, while 78% of the remaining calvings took place in the cubicle-equipped section. Thirteen percent calved in a calving pen, the remaining cows being tethered at the time of calving. Thirty-two percent of the calvings took place in houses lacking a calving pen altogether. Farmers were present during 41% of the calvings. Suckling most frequently occurred after pasture calvings, and was least frequent after calvings within the cubicle-equipped section of the cowhouse. Injuries to the calf caused by trampling or contact with fittings etc. were rare, and no more common in association with calving in the cubicle-equipped section than with calving taking place with the cow isolated from the rest of the herd. All calves were removed from their dams within 24 h after birth.

Influence of thyrotrophin-releasing hormone on thermoregulation in newborn lambs

This study examined the effect of thyrotrophin-releasing hormone (TRH) administration on thermoregulation in the newborn. Twin lambs were either delivered near-term by caesarean section or born vaginally at term. Colonic temperature, O2 consumption, CO2 production, breathing and heart rates, plus plasma thyroid hormone and nonesterified fatty acid (NEFA) concentrations and thermogenic activity (i.e. GDP binding) of brown adipose tissue (BAT) were measured. In caesarean section delivered lambs colonic temperature decreased rapidly after birth, a response that was greater in the group designated for TRH treatment, in which colonic temperature fell to below 36.0 degrees C at 80 min of life, prior to TRH administration. At this age colonic temperature had been restored to a mean of 38.70 degrees C in controls. TRH had no influence on the composition or thermogenic activity of BAT. The incidence of shivering was not influenced by TRH, but treated lambs maintained a higher rate of O2 consumption and ventilation compared with controls after colonic temperature had been restored to 38.56 degrees C. TRH appeared to promote fat oxidation as O2 consumption remained unchanged and CO2 production declined by a greater rate in treated lambs, resulting in a lower respiratory quotient compared to controls. Heart rate and plasma concentrations of NEFA increased following TRH administration although this did not result in values greater than controls. Normothermic lambs born vaginally had BAT with a greater thermogenic activity, higher plasma thyroid hormone and NEFA concentrations compared with caesarean section delivered lambs, but a thermogenic response was not observed to TRH despite a rise in thyroid hormone concentrations. In conclusion, TRH can improve thermoregulation, an effect that could be linked to an increase in fat oxidation.

Postnatal function of the somatotrophic axis in pigs born naturally or by Caesarian section

This study was designed to determine what effects the birth process would have on development of the somatotrophic axis in neonatal pigs. Eight crossbred sows were selected (n = 4 natural birth and n = 4 Caesarian section) for the present study. Blood and tissue samples from 38 pigs were collected at birth. Twenty pigs were maintained with natural birth sows until sacrificed for blood and tissue collection at 2 wk of age. Gestational age at birth did not differ (P > 0.16) between natural birth and C-section pigs. Average daily gain (ADG) from birth until 2 wk of age was reduced (P < 0.0001) by 39.3% in the C-section pigs as compared to the natural birth pigs. Serum growth hormone (GH) did not differ (P > 0.86) at birth, but was greater (P < 0.024) at 2 wk in C-section pigs. Serum insulin-like growth factor 1 (IGF-1) was greater at birth (P < 0. 0025) and at 2 wk of age (P < 0.035) in the natural birth pigs. Serum concentration of IGF-2 did not differ at birth (P > 0.8) but was greater (P < 0.043) in natural birth pigs at 2 wk of age. Pituitary content of GH mRNA and GH-releasing hormone receptor mRNA did not differ (P > 0.90) between groups regardless of age; however, expression of both mRNAs declined (P < 0.0003) from birth until 2 wk of age. There tended to be a birth type X age interaction (P < 0. 082) for liver IGF-1 mRNA such that C-section pigs had a greater expression at 2 wk of age. Liver IGF-1 mRNA expression increased (P < 0.0001) in both groups from birth to 2 wk of age. Liver expression of GH receptor mRNA was greater in C-section pigs at birth (P < 0. 04) and 2 wk of age (P < 0.03). These data provide evidence that the natural birth process affects postnatal development and/or function of the somatotrophic axis in the neonatal pig.

Caesarean section and other methods for assisted delivery: comparison of effects on mare mortality and complications

Data from 116 mares that had caesarean section or vaginal delivery at 2 university hospitals were analysed in 5 groups, as follows: dystocia corrected by caesarean section, Group DCS (n = 48); elective caesarean section, Group ECS (n = 10); caesarean section concurrently with colic surgery, Group CCS (n = 8); assisted vaginal delivery, Group AVD (n = 22); and controlled vaginal delivery under general anaesthesia, Group CVD (n = 28). Survival rate in all mares that had caesarean section, excluding Group CCS, was 88% (51/58). All mares in Group ECS survived and Group CCS had the lowest survival rate (38%). In 98 mares with dystocia, Groups DCS (15%) and AVD (14%) had significantly lower (P<0.05) mortality rates than Group CVD (29%). There were no differences between groups for duration of dystocia. The placenta was retained in 75 (65%) of 116 mares, and for a longer period following elective caesarean section than following assisted vaginal delivery. Multiple complications (> or = 3) were recorded in 6 mares in Group CVD but not in the other groups. Of the 102 foals delivered from 98 mares with dystocia, 11 (11%) were alive at delivery and 5 (5%) survived to discharge. Survival rate for foals was 38% in Group CCS, and 90% in Group ECS. Under conditions similar to those in this study, it is calculated that caesarean section is preferable to CVD if dystocia is protracted and great difficulty and trauma is involved, even if CVD allows delivery of the foal.

Quarter-milk somatic cell count at calving and at the first six milkings after calving

Thirty cows were studied during the first six milkings after calving. Quarter foremilk samples were collected by the farmers at calving and at six subsequent milkings. Geometric-mean somatic cell count (SCC) decreased from 593,000 at calving to 126,000 cells/ml at the sixth milking after calving. In quarters infected with major pathogenic bacteria, geometric-mean SCC was 3,229,000 cells/ml at calving, and 1,257,000 cells/ml at the sixth milking after calving. In quarters infected with minor pathogenic bacteria, geometric-mean SCC was 1,000,000 cells/ml at calving, and 170,000 cells/ml at the sixth milking after calving. In culture-negative quarters, geometric-mean SCC decreased from 306,000 at calving to 42,000 cells/ml at the sixth milking after calving. Quarter SCC can be used early postpartum to give an indication of intra-mammary infection status.

[Pustular dermatitis in veterinarians following delivery in farm animals; an occupational disease]

OBJECTIVE

To assess the prevalence of contact dermatitis after deliveries in cattle or sheep among veterinarians.

DESIGN

Retrospective.

SETTING

Provinces of Groningen, Friesland, and Drenthe, The Netherlands.

METHODS

By means of a short inquiry 310 veterinarians were asked whether and how often they had experienced pustular dermatitis after deliveries in cattle and sheep and what course the dermatitis had run. They were also asked about details of the deliveries (type of animal, condition of the foetus, course of the partus), about microbiological investigation, preventive measurements and therapy.

RESULTS

The response to the questionnaires was 24.5%. One or more episodes of pustular dermatitis on an arm after a delivery in cattle or sheep was noticed by 62 (81.5%) of the 76 respondents. Sometimes it was associated with secondary symptoms like headache, fever and lymphadenitis. Listeria monocytogenes (7 times out of 13) and Salmonella dublin (4/13) were the agents cultured most often.

CONCLUSION

Contact dermatitis after deliveries in cattle or sheep occurs frequently as an occupational disease of veterinarians.

Ultrasonographic pregnancy detection and inhalation anesthesia in the gray short-tailed opossum (Monodelphis domestica)

Female gray short-tailed opossums (Monodelphis domestica) with known breeding dates were anesthetized with isoflurane for ultrasonographic pregnancy detection. Beginning on gestational day 9, gravid females could be identified using a 9-MHz mechanical sector-scanning transducer equipped with a standoff pad. Fluid-filled vesicles 3 to 4 mm in diameter were seen within the thick-walled uteri on gestational days 9 and 10. Visualization revealed loss of individual vesicles, with replacement by thick, irregular uterine walls and some free luminal fluid by gestational days 12 and 13. On the basis of subsequent birth of pups, sonographic diagnosis of pregnancy was accurate in 27 of 28 oppossums examined.

Early developmental profiles of plasma corticosterone are altered by birth condition in the rat: a comparison of vaginal birth, cesarean section, and cesarean section with added anoxia

Circulating glucocorticoids play a role during the immediate postnatal period in adapting the neonate to extrauterine life and are also thought to influence tissue development and function in the later postnatal period. In the present study we have used a rat model to test whether birth by cesarean section (C-section), either alone or with an added period of acute anoxia, affects the development profile of basal corticosterone secretion during the first 5 wk of life. Plasma levels of total corticosterone and of corticosteroid-binding globulin were measured at various times after birth in rats born vaginally, by C-section, or by C-section with 15 min of added anoxia. These measures allowed for calculation of levels of free, biologically active, corticosterone. Under all conditions, total corticosterone appeared to accurately reflect levels of free corticosterone. Plasma corticosterone levels measured immediately (< 5 min) after birth were similar in male rat pups born vaginally, by C-section, or by C-section with added anoxia, whereas female pups born by C-section showed a significant increase in free corticosterone at birth, in comparison with vaginally born females. Both male and female animals born by C-section showed a reduction in plasma corticosterone at 1 h (male: 31% of control, p < 0.01; female: 45% of control, p < 0.05) and at 7 d (male: 61% of control, p < 0.01; female: 55% of control, p < 0.05) after birth, in comparison with vaginally born controls. In animals born by C-section with added anoxia, significant reductions in plasma corticosterone were observed for males at 1 h (58% of control; p < 0.05) and for females at 7 d (62% of control; p < 0.05) after birth. At 14 d of age, corticosterone levels were higher in male rats born by C-section either with (227% of control; p < 0.05) or without (239% of control; p < 0.05) added anoxia, in comparison with vaginally born controls. Thus C-section birth produces an early rise in plasma corticosterone on d 14 away from the low values associated with the adrenal quiescent period in the first 1-2 wk in the rat. By 35 d of age, there were no differences in plasma corticosterone attributable to C-section birth and/or acute birth anoxia, in either male or female rats. It is concluded that, in a rat model, birth by C-section has significant effects on the profile of plasma corticosterone during the early weeks of development, a period though to be critical for effects of corticosteroids on developing tissues. Because the rat at birth is developmentally less mature than is the term human neonate, these findings may have implications for development of the premature human neonate.

[The onset of the ovarian cycle following calving]

The onset of ovarian activity post partum was investigated by measuring progesterone concentrations in milk samples, in two dairy herds consisting of 118 cows with an average milk yield of 8340 kg FCM. Samples were taken three times a week till 50 days post partum. In 17 cows (14.4%) anoestrus occurred. The daily milk yield in this group was 2.65 kg FCM higher than the average yield in the group returning to oestrus before day 50 post partum. In cows returning to oestrus within 50 days post partum the first rise in progesterone was detected on average 27.6 days after calving. In first calvers (31.4 +/- 10.2) and in multiparous cows in the winter period (26.9 +/- 9.4) the onset of ovarian activity was delayed compared to start of ovarian activity in the summer period. In the first cycle only 28% of the cows had a normal luteal phase (12-17 days), 36% of the cows had a shortened luteal phase (less than 6 days), and 24% of the cows had a short luteal phase (6-11 days). In 12% of the cows the luteal phase was longer than 17 days. In the second cycle 56% of the cows had a normal luteal phase while 17% had a shortened luteal phase, and 17% had a short luteal phase. Pregnancy rates after first insemination in cows with a short dioestrus (10-25 days) were higher than in cows with a prolonged dioestrus (26-50 days). On the basis of these result it might be expected that postponing the first insemination until the second or even the third cycle in high-yielding cows will have only a marginal effect on the number of open days and a large effect on the number of inseminations per pregnancy.

[Pustular dermatitis in veterinarians following delivery in domestic animals; an occupational disease]

OBJECTIVE

To assess the prevalence of contact dermatitis after deliveries in cattle or sheep among veterinarians.

DESIGN

Retrospective.

SETTING

Provinces of Groningen, Friesland and Drenthe, The Netherlands.

METHODS

By means of a short inquiry 31O veterinarians were asked whether and how often they had experienced pustular dermatitis after deliveries in cattle and sheep and what course the dermatitis had run. They were also asked about details of the deliveries (type of animal, condition of the foetus, course of the partus), about microbiological investigation, preventive measurements and therapy.

RESULTS

The response to the questionnaires was 24.5%. One or more episodes of pustular dermatitis on an arm after a delivery in cattle or sheep was noticed by 6(2) (81.5%) of the 7(6) respondents. Sometimes it was associated with secondary symptoms like headache, fever and lymphadenitis. Listeria monocytogenes (7 times out of 13) and Salmonella dublin (4/13) were the agents cultured most often.

CONCLUSION

Contact dermatitis after deliveries in cattle or sheep occurs frequently as an occupational disease of veterinarians.

[Adaptation reaction of dairy calves in the first days of life. Effects of type of delivery and individuality of the newborn]

Surveying a calving period of tethered dairy cows, newborn dairy calves of different breeds were investigated just after birth and at 24 hours and 48 hours of their postnatal life as well. Blood samples taken by venipuncture in calves were analyzed for acid-base-balance, hemoglobin, catecholamine and cortisol. Comparing the mean values of the newborns from calvings without assistance, with slight pulling and with heavy pulling, differences could be found only in the first hours of postnatal life between some of them without hemoglobin content of the blood that was of individually specificity and all the time lowest in calves delivered by heavy traction. Great scattering of and strong relationship between some of the measured values are assessed on the basis of constitutional features, maturity and adaptability of the calves.

[Non-recognition of a second fetus in a recumbent cow during veterinary obstetrical assistance (expert opinion)]

The objective of the expert opinion presented in this paper is the missing of a second fetus after veterinary obstetrical assistance in a downer cow. The necessity of a thorough examination after obstetrical manipulation is stressed with special reference to problems occurring in recumbent cows. In addition, possible complications after inappropriate removal of retained placental fetal membranes are discussed.

Causes of perinatal lamb mortality amongst Dormer and SA Mutton Merino lambs

Perinatal lamb deaths were investigated in Dormer (n = 290) and SA Mutton Merino (n = 306) progeny born to 166 and 147 ewes respectively. Causes of mortality were investigated by autopsy in 30 Dormer and 61 SA Mutton Merino lambs that died during the perinatal period. Perinatal lamb deaths were higher (P < or = 0.01) in SA Mutton Merino lambs than in Dormers (0.199 vs 0.103). Anteparturient deaths (APD) were confined almost exclusively to triplet lambs, and contributed 10-12% of the overall perinatal lamb mortalities in both breeds. This category was closely associated with prolonged parturition, with 86% of the 7 ewes involved needing assistance after more than 4 h. The majority of parturient deaths (PD) were associated with stressful births, which contributed a higher (P < or = 0.05) proportion of total perinatal deaths in SA Mutton Merino lambs than in Dormers (0.508 vs 0.267). Ewes giving birth to litters consisting of one or more lambs in the birth stressed PD or birth stressed post parturient death (PPD) categories (also including APD deaths because of their obvious relationship to prolonged births), furthermore had longer (P < or = 0.05) parturitions than contemporaries that lost one or more lambs as a result of other causes, or ewes that reared all lambs born through the perinatal period (214 vs 98 and 74 min respectively). Uncomplicated starvation/mismothering/exposure (SME) syndromes mostly contributed to the PPD category, and constituted 21-27% of perinatal lamb deaths in the 2 breeds. Deaths with clinical signs of SME could mainly be related to udder malfunction, which was observed in nearly 60% of the cases.(ABSTRACT TRUNCATED AT 250 WORDS)

[Reproduction of beef cattle]

The literature on the reproduction of beef cattle is reviewed in the present paper. To begin with the differences between dairy and beef cattle are elucidated. Secondly, the most important reproductive problems of beef cows are discussed. Items discussed include: the arrival of puberty, the interval between parturition and the first service and infertility. In Belgium, where nearly all beef cows belong to the double muscled White and Blue breed and have to be delivered by caesarean sections, many fertility problems are due to adhesions between the uterus and the surrounding tissues. Besides the quality of the semen of many of the bulls used is rather poor. This is probably caused by the extreme selection for beef production. Finally, the criteria which should be used to determine the reproductive efficiency of beef cows are discussed. Such as the percentage of pregnant cows, the proportion of live and weaned calves and the calving interval.

Correlations between calving ease and calf survival

Multitrait restricted maximum likelihood methods were used for estimation of heritabilities and genetic and phenotypic correlations between calving ease and calf survival. These analyses examined both direct and maternal effects. Genetic correlation for direct effects between calving ease and calf survival was approximately -.8 in both heifers and cows, indicating favorable associations, whereas phenotypic correlations were -.32 and -.22.