Ultrasonographic examination of postpartum uterine involution in sows

Use of chorionic gonadotropins during lactation to optimize postpartum sow reproductive performance: a review

Treating lactating sows with chorionic gonadotropins may allow controlling their post-weaning reproductive function, despite the occurrence of anestrous during lactation. This article reviews the potential effectiveness of treatment with both equine and human chorionic gonadotropins (eCG and hCG, respectively) during lactation on the control of estrus expression and ovulation in weaned sows. The use of 1,000 IU hCG at 24 and 48 h postpartum may induce ovulation in the treated sows, but the ovulation rate may be variable. Pregnancy rates may be improved with combined treatment after the second week of lactation with both chorionic gonadotropins: 1,500 IU eCG plus 500 - 1,000 hCG; or 1,000 IU eCG plus 1,000 IU hCG. Treatment with eCG (1,000 - 2,000 IU) at the end of lactation may result in acceptable estrus expression and ovulation rates, although with marginal benefit for pregnancy rates. The subsequent response to treatments with chorionic gonadotropins during lactation is likely influenced by the treatment period, the suckling frequency during lactation, and the boar exposure during the weaning-to-estrus interval. A better understanding of the efficiency of such steroid-free treatments is increasingly relevant due to the constraints of the use of steroid hormones in livestock reproductive management.

Effects of free farrowing system on the productive performance and welfare of sows and piglets

Regardless of international animal welfare regulations, most sows in production currently spend most of their lives and the peripartum period in caged housing systems. Although this type of management is intended to reduce neonatal mortality in piglets, several studies consider that there has been no significant reduction in its incidence over the last 30 years. On the contrary, cage housing has promoted the appearance of alterations during the farrowing process such as dystocia, as well as in maternal behavior and health, promoting stereotypes, skin lesions and other alterations, which not only impact the sows but also their progeny during the lactational period. Therefore, the aim of the present review is to compare the productive performance and welfare of sows and their piglets within the farrowing, lactation, and post-weaning period in both traditional and free-farrowing systems, highlighting the differences in these indicators in each of them.

General and comparative aspects of endometritis in domestic species: A review

Endometritis is a leading cause of sub- and infertility in domestic animal species. The healthy uterus is colonized by commensal bacteria, viruses and yeast/fungi that represent the nonpathogenic microbiota. A shift in the number or type of organisms accompanied by immune dysfunction, however, may trigger uterine infection and inflammation. Metritis is associated with inflammation of all uterine layers (endometrium, myometrium and perimetrium), whereas endometritis is a more superficial inflammation involving solely the endometrium. Endometritis generally occurs at two time points in domestic animal species, postpartum and postmating. Postpartum endometritis may chronically persist, either as a low-grade disease that often manifests as a vaginal discharge but not a systemic illness (in some species termed clinical endometritis) or sometimes subclinical where features are only detected by endometrial sampling. Contamination of the uterus at the time of mating occurs by direct deposition of semen (ejaculated or artificially inseminated) into the uterus. Improper drainage of the ejaculatory fluid or an inadequate immune response may result in persistent mating-induced endometritis. Both postpartum and postmating endometritis interferes with fertility by creating a suboptimal environment for embryo development and placentation, and chronic endometritis may have an impact on sperm survival and fertilization ability. In the postpartum animal, there may also be changes in milk production and maternal behaviour, which can affect offspring health and survival. Preventive strategies for endometritis largely depend on monitoring their known risk factors, which are sometimes specific with regard to the species. Effective, nonantibiotic therapy for endometritis is not available to date. Overall, extensive research has been performed in cattle and horses to unravel key aspects of endometritis, but in sows and bitches, the available literature is scant. Thus, the need and opportunity to investigate the condition vary considerably among domestic species and necessitate their comparative assessment. This article reviews general and comparative aspects of the diagnosis and classification, pathogenesis, preventive strategies and therapeutics of endometritis in domestic species with a specific focus on cows, mares, sows and bitches.

Reproductive health of the sow during puerperium

The modern hyperprolific sow is susceptible to metabolic disease and chronic inflammation. The most sensitive phase is parturition, when the sow experiences systemic inflammation and stress, and major changes in metabolism and endocrinology. Resolution of inflammation and stress needs to happen quickly to ensure good reproductive health during puerperium. If the sow fails to adapt to these changes, puerperal disease may occur. The economically most important puerperal disease complex is the postpartum dysgalactia syndrome (PPDS). Other puerperal diseases include infections of the urogenital tract. Diagnosis of PPDS and urogenital disease on-farm is challenging but several diagnostic methods, including clinical examination, behavioral observations, ultrasonography and biomarkers are available. Ultrasonography is an excellent tool for monitoring the health of the urogenital tract, the mammary gland, and uterine involution and guide further diagnostic interventions. Biomarkers such as Chromogranin A, tumor necrosis factor-α, and interleukin-6 represent promising tools to monitor general health and the systemic state of inflammation and oxidative stress of the sow. Nonsteroidal anti-inflammatory drugs, dopamine antagonists, and oxytocin are promising to address the symptoms of PPDS. Reducing of stress, improving nutrition and intestinal health, and supporting animal welfare-friendly husbandry help in the prevention of PPDS.

Evaluation of different point-of-care tests to characterize the vaginal discharge of sows after parturition and parameters' correlation with subsequent reproductive performance

The lochia is the physiological uterine discharge post-partum, whereas abnormal fluids are often indicators of puerperal disorders in sows, which negatively influence the further reproductive performance. The aim of the study was to characterize the vaginal discharge in sows employing simple and feasible tests and to correlate the evaluated parameters with the subsequent reproductive performance of these sows. The birth process of 48 clinically healthy free farrowing sows was monitored and several parameters characterizing the vaginal discharge such as total amount, colour, amount of cells (somatic cell count) and cell characteristics (cytology) were collected daily from first to fifth day after parturition. Finally, the reproductive performance of the following gestation was evaluated and compared to the characteristics of the lochia. The amount of vaginal discharge was significantly increased on the second (p < 0.01), third (p = 0.019) and fourth (p = 0.011) day post-partum compared to day one. Furthermore, a decrease in the percentage of neutrophilic granulocytes from day one to three (p = 0.038), four (p = 0.038) and five (p = 0.048) post-partum was observed. The percentage of neutrophilic granulocytes in the yellowish vaginal discharge was increased compared to whitish (p = 0.02) or clear (p = 0.027) vaginal discharge. In addition, obstetrics (p = 0.003) and an increased farrowing duration (p = 0.017) significantly increased the amount of vaginal discharge. Sows with a high amount of vaginal discharge had a significant higher body temperature than sows with no (p = 0.014) or low amount (p < 0.01) of vaginal discharge. No correlation was detected between the evaluated parameters of the lochia and the subsequent reproductive performance. It is hypothesised that the amount of vaginal discharge alone is not a predictor for the performance of sows during their next gestation. However, it might serve as indicator for acute endometritis. In summary, the different parameters of the vaginal discharge determined by means of point-of-care tests might be useful to strengthen a presumptive diagnose of endometritis in sows during the first five days after parturition.