Oestrus In Sows Research Articles

Circadian temperature rhythm in breeding sows: differences between days in oestrus and anoestrus after weaning

BackgroundMammals are subject to circadian rhythms for the control of various physiological events. One of the parameters known to be subject to variations throughout the day is body temperature, which is also subject to influences such as environmental temperature. However, there are not many studies on these rhythms in breeding sows. The aim of this study was to determine the circadian parameters for body temperature in post-weaning sows during oestrus period, throughout the seasons in a warm climate.ResultsDifferences were observed in inter-daily stability, intra-daily fragmentation and cycle length comparing the summer sows with the other seasons. Differences were also observed in the period that the sows were in oestrus compared to the non-oestrus period for intra-daily fragmentation, with these differences being more important in the warm seasons compared to the cold seasons. The parameters normalised by COSINOR also showed significant differences when comparing seasons, especially in the acrophase of the temperature maximum. Another significant finding was an increase in vaginal temperature during oestrus in sows monitored in summer compared to the other seasons. Correlations between body, vaginal and environmental temperature were observed.ConclusionThere is a seasonal influence on the circadian rhythm of temperature and summer is clearly the season with the greatest differences in circadian parameters when compared to the other seasons. The extreme summer conditions seem to definitely influence this rhythm and make the body and vaginal temperature of the sows different from the rest of the year. The increase in period robustness in both body and vaginal temperature during the days when sows are in oestrus could be related to the hormonal events of oestrus and ovulation and seems to be independent of weather since it occurs in all controlled seasons. However, this robustness is significantly higher in summer than in the other seasons both in the oestrus period and on days when sows are not in oestrus.

Developing a Sow Vulva Volume Estimation Pipeline Based on LiDAR Imagery and Deep Learning

Highlights An artificial intelligence-enabled imagery data processing pipeline. Sow vulva swelling can be quantified using imagery automatically. Biological signs of sow estrus are quantified. Abstract. Accurate and timely estrus detection is one of the critical factors for improving the conception rate of sows in swine reproduction. Estrus detection in the current industry relies on experienced breeding technicians using the back pressure test method, which is time-consuming, labor-intensive, and subjective. This study aimed to develop an image-processing pipeline that could predict the onset of estrus by monitoring the variation of the vulva volume of sows. A robotic imaging system consisting of a LiDAR camera was used to collect depth and infrared (IR) images of sows multiple times per hour. The developed image processing pipeline consisted of a deep learning model (MobileNet) to exclude images with defective postures (e.g., excreting posture, vulva region not showing) for vulva detection. The selected images were further processed to (1) segment sow vulva regions (3-dimensional surface) using a U-Net model, (2) exclude incorrectly segmented 3D vulva surfaces using a MobileNet model, and (3) calculate the vulva volume using the segmented 3D vulva surface. Results show that all three models achieved high test accuracy of 94.8% (MobileNet 1), 96.7% (U-Net), and 100% (MobileNet 2). The vulva volume was calculated using the developed pipeline for all the test sows. Daily average vulva volume showed a noticeable increase in all sows at 0-1 day prior to the onset of estrus. This study concluded that the developed image processing pipeline could automatically detect vulva swelling, which may be used as a biological sign indicating the onset of post-weaning estrus in sows. Keywords: 3D camera, Digital agriculture, Estrus detection, Robotic imaging system, Swine reproduction.

Identification of Estrus in Sows Based on Salivary Proteomics.

Simple SummaryThe conception rate of sows is an important factor affecting the efficiency and income of pig farms. At present, the traditional estrus identification methods used in production, such as the external observation method and back pressure reaction method, have the disadvantages of being time-consuming and laborious, with low accuracy and high requirements for technicians. In addition, the abnormal estrus status of sows, such as continuous estrus and short estrus, will also lead to misjudgment during estrus inspection, which will affect the conception rate of sows and reduce production efficiency. Therefore, the purpose of this study was to explore a new method for estrus identification, to provide an important reference for accurate estrus identification of sows by screening salivary proteins related to estrus, and to provide a reference for the development of kits/strips for estrus identification of sows.The estrus cycle of multiparous Large White sows was divided into three stages to solve the problems of heavy workload and low accuracy of the traditional estrus identification method in pig production. Saliva protein was extracted from the oral saliva of multiparous sows. Label-free quantitative proteomics was used to detect salivary proteome, and MaxQuant software was used for quality control. Results showed that 246 proteins were identified in the three stages, where 40 proteins were significantly different (p < 0.05). The total proteins identified were enriched by STEM software and the protein function was annotated by using the ClueGO plug-in in the Cytoscape software. The results were enriched to eight different trends. The annotated items were related to protein synthesis and processing and estrogen response. Gene ontology and the Kyoto Encyclopedia of Genes and Genomes enrichment analysis of differential proteins involved in the pathways and entries included oocyte meiosis, response to estradiol, and oogenesis. Further interaction analysis showed that an interaction occurred between P00355, F1SHL9, P28491, F1SDR7, F2Z558, F1RYY6, and F2Z5G3 proteins. The findings served as a basis for revealing the changes in salivary protein content in the sow estrus cycle and provided a reference for the development of an estrus identification kit/test strip in the next step.

Integrative analysis of transcriptome complexity in pig granulosa cells by long-read isoform sequencing.

BackgroundIn intensive and large-scale farms, abnormal estradiol levels in sows can cause reproductive disorders. The high incidence rate of reproductive disturbance will induce the elimination of productive sows in large quantities, and the poor management will bring great losses to the pig farms. The change in estradiol level has an important effect on follicular development and estrus of sows. To solve this practical problem and improve the productive capacity of sows, it is significant to further clarify the regulatory mechanism of estradiol synthesis in porcine granulosa cells (GCs). The most important function of granulosa cells is to synthesize estradiol. Thus, the studies about the complex transcriptome in porcine GCs are significant. As for precursor-messenger RNAs (pre-mRNAs), their post-transcriptional modification, such as alternative polyadenylation (APA) and alternative splicing (AS), together with long non-coding RNAs (lncRNAs), may regulate the functions of granulosa cells. However, the above modification events and their function are unclear within pig granulosa cells.MethodsCombined PacBio long-read isoform sequencing (Iso-Seq) was conducted in this work for generating porcine granulosa cells’ transcriptomic data. We discovered new transcripts and possible gene loci via comparison against reference genome. Later, combined Iso-Seq data were adopted to uncover those post-transcriptional modifications such as APA or AS, together with lncRNA within porcine granulosa cells. For confirming that the Iso-Seq data were reliable, we chose four AS genes and analyzed them through RT-PCR.ResultsThe present article illustrated that pig GCs had a complex transcriptome, which gave rise to 8,793 APA, 3,465 AS events, 703 candidate new gene loci, as well as 92 lncRNAs. The results of this study revealed the complex transcriptome in pig GCs. It provided a basis for the interpretation of the molecular mechanism in GCs.

Neither frozen-thawed seminal plasma nor commercial transforming growth factor-β1 infused intra-utero before insemination improved fertility and prolificacy in sows.

Seminal plasma (SP) affects reproduction, inducing cell and molecular changes in the female genital tract. A main active component in SP is the modulatory transforming growth factor-β (TGF-β), particularly its TGF-β1 isoform, which affects the synthesis of other cytokines as granulocyte-macrophage colony-stimulating factor, relevant for embryo development and pregnancy. This study evaluated the effect of pooled frozen-thawed SP and commercial TGF-β1 infused during oestrus in sows post-cervically inseminated with liquid extended semen, containing ~4ml of residual SP, on their fertility and prolificacy. For this, 250 sows in their post-weaning oestrus were used. Sows were randomly assigned to one of the following groups to be post-cervically treated 30min before insemination: (i) SP group: infused with 40ml of SP (N=57); ii) Group TFGß1 : infused with 40ml of BTS extender containing 3ng/ml of porcine TGF-β1 (N=64); iii) BTS group: infused with 40ml of BTS extender (N=60); and iv) Control Group: sows catheterized but not infused prior to AI (N=69). Farrowing rates (range: 86.7% to 91.3%) and numbers of live-born piglets (range: range: 12.8±2.9 to 13.4±3.1) were not affected by any treatment compared with Controls, indicating that neither pre-infusions of SP nor TGF-ß1 30min before AI influenced subsequent fertility and prolificacy.

Such a tease! Production and uses of teaser rams, bucks, boars and bulls

Background: Male livestock rendered sterile through vasectomy or epididymectomy, but still hormonally and behaviourally sexually active, have many uses. In small ruminants they can be used to advance the breeding season and puberty, synchronise and detect oestrus and improve conception rates to artificial insemination. In pigs, they can be used to hasten first oestrus in gilts and detect oestrus in sows. In cattle, they can be used to aid heat detection for artificial insemination.Aim of the article: This article outlines the surgical techniques used to produce such ‘teaser’ animals and discusses how they can be best used, as well as the alternatives to their use.

PSII-13 Supplemental Effects of Unrefined Fish Oil, Powdered/Coated Docosahexaenoic Acid on the Growth Performance in Weaner Pigs

Abstract A total of 18 sows (Landrace × Yorkshire) with an average body weight of (within 24 h after farrowing) were used for a 5- week experiment to determine the effects of varying dietary Valine, Lysine (V:L) ratios on performance and fecal score in lactating sows and litters. Sows were raised in individual pens, and assigned to one of three experimental diets consisting different concentration of Valine, Lysine ratios (0.83%, 0.85% and 0.88%). sows body weight was significantly improved by 0.85% valine and lysine ratio compared to 0.85% and 0.88%. However, no significant difference were observed on sows body weight loss, back fat thickness, average daily feed intake and days to return to estrus of sows during the three experiment period. In addition, growth performance of piglet weaning weight were significantly improved by 0.85% valine and lysine ratio compared to 0.85% and 0.88%. Morever, piglet average daily gain was significantly increased 0.88% valine and lysine ratio compared to 0.83% and 0.85%. The three dietary treatments had a significant differences (P&amp;gt;0.05) on fecal score of sows, farrowing and 14 d old age piglets were significantly observed by valine and lisiune ratio. In conclusion, Valine, Lysine had no positive effects on the fecal score of sows and litter during lactation and also no positive effect on gut and its microflora.

Ovulation and fertility responses for sows receiving once daily boar exposure after weaning and OvuGel® followed by a single fixed time post cervical artificial insemination

Boar exposure is used to stimulate follicle development and estrus in sows after weaning and also to improve semen uptake and sperm transport with insemination. However, the need and value of boar exposure is uncertain when ovulation induction is used. These studies were designed to determine the effect of daily boar exposure after weaning when used with ovulation induction and fixed time post-cervical artificial insemination (PCAI). In experiment 1, sows were weaned into stalls and assigned to receive 3 min of daily fenceline boar exposure (BE, n = 7) or no boar exposure (NBE, n = 8). All sows received OvuGel at 96 h after weaning and BE or NBE 30 min prior to a single PCAI 24 h after OvuGel. Ovaries were assessed daily for follicle size from weaning until ovulation. Cervical contractions were measured 30 min following BE or NBE and before PCAI, while uterine contractions were measured for 1 h following PCAI. In experiment 2, weaned sows (n = 244) were assigned by parity to receive once daily BE for 1.5 min each day or NBE. OvuGel, PCAI and ultrasound methods were performed similarly as in experiment 1. Results from experiment 1 indicated BE did not significantly influence follicle size or measures of fertility. However, BE did increase the frequency of cervical contractions (P < 0.05), but with no effect on the uterus. Results from experiment 2 indicated BE had no effect on catheter passage for PCAI but did increase the proportion of sows ovulating within 48 h after OvuGel (77.7 vs 67.5%, P = 0.05), and tended (P = 0.10) to increase the proportion of sows inseminated 24 h before ovulation (70.3 vs. 61.0%). However, BE had no effect on adjusted farrowing rate (84.4 vs. 77.4%) or total pigs born (13.2 vs. 12.5) for BE and NBE, respectively. There were treatment and parity interactions for follicle size at time of OvuGel and at time of PCAI (P < 0.05) with BE minimizing parity effects on follicle size. Parity effects were also evident on farrowing rate and litter size when inseminations occurred >24 h from ovulation but not when inseminations occurred ≤24 h before ovulation. The results indicate that boar exposure for only minutes each day after weaning had beneficial effects for improving follicle development, ovulation induction, and AI timing, most notably in parity 1 sows, but had no beneficial or detrimental effects on the ability to perform PCAI.

Investigation into the effect of season on oestrus in gilts over two years of climate adaptation

This study examined the changes in age at first oestrus, the weaning-to-oestrus interval (WEI), and duration of oestrus (DE) in a Yorkshire sow population during two years of adaptation from a northern (55°48′N, 9°13′W) European region to a southern (44°03′N, 23°35′W) one. The adaptation process induced a grouping effect of gilts around the mean age of the onset of puberty. Autumn and spring were characterized by the most enhanced gilt grouping effect at 201 to 210 days of age. The same effect was found for oestrus duration, which declined from a 12- to 96-hour range in the first year to an 18- to 90-hour range in the second year. The mean age of first oestrus was 0.8 days significantly lower in the second year compared with the first; the maximal lowering (1.7 days) occurred in the winter season. The WEI decreased significantly from the first to the second year in all four seasons, by a mean annual value of 0.88 days (15.9%). DE increased by 6.5 hours (significantly for all seasons) from the first year to the next. DE showed an ascending evolution from winter to spring and descending from summer to autumn, during each monitored year. Adaptation influences the oestrus in sows. The age to puberty and WEI tended to decrease, while DE tended to increase, with a simultaneous decrease in the variability of these oestrus parameters.

Relationship of vaginal impedance with speed of return to oestrus after weaning, oestrous behaviour, parity and lactation length in cyclic sows

The effect of weaning to oestrus interval, oestrus duration, parity, lactation length, breed and their interactions on changes of vaginal impedance in sows after weaning and during oestrus was examined. The impedance measurements were carried out by a four-electrode method. The interval from weaning to oestrus was significantly longer in sows with the length of lactation 21–25 days than 26–30 days and 31–36 days and in primiparous than multiparous sows. The interval from weaning to oestrus was negatively correlated with the length of lactation ( r = −0.21; P < 0.05), parity ( r = −0.36; P < 0.01) and oestrus duration ( r = −0.26; P < 0.01). The weaning to oestrus interval, oestrus duration, parity and lactation length had a significant effect and the breed of sows had no influence on the vaginal impedance in peri-oestrus. The decrease of vaginal impedance after weaning was delayed in sows with a longer weaning to oestrus interval and in primiparous than multiparous sows. The decline of vaginal impedance during peri-oestrus was more gradual in sows with a longer interval from weaning to oestrus, shorter lactation, primiparous sows and sows with the length of oestrus 36 h and 72 h and more. The nadir of vaginal impedance occurred earlier before oestrus in sows with a shorter oestrus. The interaction of weaning to oestrus interval with parity and oestrus duration and the interaction of oestrus duration with parity significantly affected the vaginal impedance in weaned sows. In conclusion, the weaning to oestrus interval, oestrus duration, parity and lactation length considerably influence the vaginal impedance in sows during peri-oestrus. The findings indicate that the impedance technique may be a useful method for a study of factors and processes that accelerate or slow down the return to oestrus after weaning and affect oestrus duration in sows.

Effects of artificial boar stimuli on the expression of oestrus in sows

In this study, the effects of artificial boar stimuli on oestrus expression in sows were compared to that of a boar. During consecutive cycles, 12 gilts and 38 sows were subjected to one of the three treatments. A Back-Pressure-Test (BPT) was carried out twice daily in the presence of a robot boar (R) with: (1) olfactory and auditory stimuli (R + O + A), (2) auditory stimuli (R + A) or (3) without additional stimuli (R). As a reference, a BPT was carried out in the presence of a mature boar 30 min after the robot procedure. With the boar, detection rate was higher (100% versus 66% (R + O + A), 81% (R + A), and 75% (R); P < 0.01) and the duration of oestrus was longer (56 ± 7 h versus 33 ± 4 h (R + O + A), 54 ± 5 h versus 36 ± 5 h (R + A), and 60 ± 3 h versus 38 ± 3 h (R); P < 0.01) than with any combination of artificial boar stimuli. The different combinations of artificial stimuli did not differ in detection rate and duration of oestrus ( P > 0.10). Artificial, olfactory and auditory stimuli did not add to the visual stimuli. Furthermore, the presence of a boar results in better oestrus expression than a combination of all artificial stimuli.

Effects of boar contact and housing conditions on estrus expression in sows

In this paper, the authors review the effects of boar contact and different components of boar presence on onset and expression of estrus in weaned sows. Evidence is presented that boar contact may influence LH release, onset of follicle development and timing of ovulation after weaning. Once the sow is in estrus it is important that she shows estrous behavior, because her expression of estrus determines whether she will be inseminated. Boar contact or components thereof affect expression of estrus in sows. There are distinct differences between different components of boar contact in their effectiveness in the induction of estrous behavior (standing response) in sows. Habituation to boars (due to frequency of boar contact or housing of boars near sows) also affects estrus expression in sows. It is important to inseminate sows at the correct moment relative to ovulation. The use of different estrus detection protocols (e.g., by giving sows different levels of boar stimuli during estrus detection) may result in the definition of distinct periods of estrus that may help to predict the moment of ovulation. However, results to date are not very encouraging. Besides boar stimuli, the housing conditions of sows may affect onset of estrus and estrus expression. This paper focuses on social sow-to-sow interactions. The effects of group housing (as compared to individual housing) on onset of estrus and expression of estrus are equivocal. These effects likely depend on factors like aggression between pen mates, reproductive status of pen mates and social rank of sows within the group.

Níveis de lisina em ração de lactação para fêmeas suínas primíparas

Foram utilizadas 40 porcas mestiças (Landrace x Large White) de primeiro parto, com peso médio de 182,2 ±16,5 kg para avaliar diferentes níveis de lisina total (0,95; 1,03; 1,10; 1,18; e 1,25%) na ração, mantendo-se a mesma relação de aminoácidos, durante a lactação (21 dias). Utilizou-se o delineamento de blocos ao acaso com cinco tratamentos, oito repetições, sendo a porca considerada a unidade experimental. O consumo total de ração não variou entre os tratamentos, com as porcas consumindo, em média, 4,2 kg de ração por dia. O consumo de lisina e o peso das porcas à desmama aumentaram de forma linear, em razão do nível de lisina das rações. Embora a variação de peso das porcas não tenha sido significativa, as porcas que consumiram as rações com níveis de lisina iguais ou superiores a 1,18% apresentaram menores valores absolutos de perda de peso durante a lactação. O ganho de peso e o peso à desmama dos leitões e da leitegada, a espessura de toucinho e o número de dias para a retomada do estro das porcas após a desmama não foram influenciados pelos níveis de lisina da ração. Concluiu-se que o nível de 0,95%, correspondente a um consumo diário de 40 g de lisina total, atende às exigências de lisina de porcas primíparas em lactação.

Myometrial activity around estrus in sows: spontaneous activity and effects of estrogens, cloprostenol, seminal plasma and clenbuterol

A new, nonsurgical, open-end catheter technique was used to study spontaneous uterine activity around estrus in sows, and the effects of estrogens, seminal plasma, cloprostenol, and clenbuterol on uterine activity. In the first experiment, uterine activity was studied in 14 multiparous, cyclic sows, during one or more estrous cycles, from day −4 to day 4 of the cycle (day 0: first day of standing estrus). From a few days before estrus until estrus, the percentage of sows showing any uterine contractions increased from 55 to 100%, and frequency and mean amplitude of uterine contractions for these sows increased from 15 to 22/h, and from 20 to 40 mmHg on average. After estrus, uterine activity decreased. There were large differences between sows in uterine activity, which were consistent over the days of the cycle. In the second experiment, 11.5 μg of estrogens in 100 ml saline ( n=17), 100 ml seminal plasma ( n=5), 1 mg cloprostenol in 100 ml saline ( n=10), 0.30 mg clenbuterol in 100 ml saline ( n=11), or 100 ml saline ( n=5) was infused IU, after recording spontaneous activity. Infusion with saline or seminal plasma did not affect uterine activity. Estrogens increased frequency of contractions. Cloprostenol increased both frequency and amplitude of contractions. Clenbuterol reduced both frequency and amplitude of contractions. In conclusion, this study shows that spontaneous uterine activity in sows is increased around estrus, and it supports the role of estrogens in boar seminal plasma in affecting uterine activity around mating. Further, this study has yielded possible tools to study the relation between uterine activity and sperm transport.

Vasectomy in the pig

VASECTOMISED or teaser boars have long been recognised as being a useful tool in the manipulation of oestrus in sows. The boar provides the greatest stimulus for oestrus and is...

Synchronization of the Estrous Cycle in Sows Using a Controlled Intravaginal Drug-releasing Device.

The aim of this study was to determine the effectiveness of an intravaginal drug-releasing device commercially produced for use in goats and sheep (CIDR-G device) at inducing estrus in sows. Thirteen Landrace sows were used in the this study, and the sows were randomly divided into three groups: group A (n=5), group B (n=4) and group C (n=4). Two CIDR-G devices were inserted into the vagina of each sow in groups A and B, and one CIDR-G device was inserted into the vagina of each sow in group C. The device was removed from each sow on the seventh day after insertion, and 0.2625 mg of PGF2α was applied to the vulva of each sow in groups A and C. All five sows in group A and all four sows in group C, the two groups of sows that were administered PGF2α, showed onset of estrus 3-5 days and 2-4 days after removal of the CIDR-G device, respectively. Three of the four sows in group C showed onset of estrus on the second day after removal of the device. On the other hand, onset of estrus was observed (on day 3 after removal of the device) in only one of the four sows in group B, the group of sows that were not administered PGF2α. Saliva progesterone concentrations continued to rise in both groups A and C after insertion of the device, and the saliva concentrations of progesterone on day 5 after insertion in these two groups were significantly higher than those just prior to insertion of the device (p<0.05). The number of devices inserted had no effect on the saliva progesterone concentration. The results of this study showed that insertion of a CIDR-G device for a period of seven days followed by application of PGF2α to the vulva is effective for induction of estrus in the swine.

Factors regulating Initiation of Oestrus in Sows

Reproduction in Domestic AnimalsVolume 33, Issue 3-4 p. 119-123 Factors regulating Initiation of Oestrus in Sows S Einarsson, Corresponding Author S Einarsson Department of Obstetrics and Gynaecology. Department of Animal Physiology. Centre for Reproductive Biology, Swedish University of Agricultural Sciences, Uppsala, SwedenAuthors' Address: Dept. of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Swedish University of Agricultural Science, Box 7039, S-750 07 Uppsala, SwedenSearch for more papers by this authorA Madej, Corresponding Author A Madej Department of Obstetrics and Gynaecology. Department of Animal Physiology. Centre for Reproductive Biology, Swedish University of Agricultural Sciences, Uppsala, SwedenAuthors' Address: Dept. of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Swedish University of Agricultural Science, Box 7039, S-750 07 Uppsala, SwedenSearch for more papers by this authorM Sterning, Corresponding Author M Sterning Department of Obstetrics and Gynaecology. Department of Animal Physiology. Centre for Reproductive Biology, Swedish University of Agricultural Sciences, Uppsala, SwedenAuthors' Address: Dept. of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Swedish University of Agricultural Science, Box 7039, S-750 07 Uppsala, SwedenSearch for more papers by this author S Einarsson, Corresponding Author S Einarsson Department of Obstetrics and Gynaecology. Department of Animal Physiology. Centre for Reproductive Biology, Swedish University of Agricultural Sciences, Uppsala, SwedenAuthors' Address: Dept. of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Swedish University of Agricultural Science, Box 7039, S-750 07 Uppsala, SwedenSearch for more papers by this authorA Madej, Corresponding Author A Madej Department of Obstetrics and Gynaecology. Department of Animal Physiology. Centre for Reproductive Biology, Swedish University of Agricultural Sciences, Uppsala, SwedenAuthors' Address: Dept. of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Swedish University of Agricultural Science, Box 7039, S-750 07 Uppsala, SwedenSearch for more papers by this authorM Sterning, Corresponding Author M Sterning Department of Obstetrics and Gynaecology. Department of Animal Physiology. Centre for Reproductive Biology, Swedish University of Agricultural Sciences, Uppsala, SwedenAuthors' Address: Dept. of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Swedish University of Agricultural Science, Box 7039, S-750 07 Uppsala, SwedenSearch for more papers by this author First published: 09 October 2007 https://doi.org/10.1111/j.1439-0531.1998.tb01328.xCitations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Citing Literature Volume33, Issue3-4June 1998Pages 119-123 RelatedInformation

Effect of exogenous gonadotropins on the weaning-to-estrus interval in sows

The efficacy of PG 600 (400 IU PMSG and 200 IU hCG) for accelerating the onset of estrus was determined for sows weaned during the summer. Yorkshire sows (average parity = 4.6), nursing 8.6 ± 0.2 pigs (mean ± SEM) were weaned after 27.7 ± 0.4 d of lactation and were treated intramuscularly with either PG 600 (n = 35) or with 0.9% saline (n = 35). Sows were checked for estrus once daily in the presence of a mature boar. Treatment with PG 600 increased (P < 0.05) the percentage of sows in estrus within 7 d after weaning (97.1 vs 82.9%). Relative to controls, sows given PG 600 expressed estrus sooner (3.8 ± 0.1 d vs 4.5 ± 0.1 d; P < 0.01). Sows exhibiting estrus within 7 d after treatments were artificially inseminated 0 and 24 h after first exhibiting estrus. The percentage of inseminated sows that farrowed tended to be higher (P < 0.07) for control than for PG 600-treated sows (96.6 vs 82.3%). The number of pigs born live was similar (P > 0.1) for sows treated with PG 600 and with saline, and was 12.7 ± 0.6 and 11.7 ± 0.7, respectively. Pigs farrowed by saline-treated sows, however, tended to be heavier (P < 0.09) than pigs farrowed by sows treated with PG 600 (1.49 ± 0.06 kg vs 1.34 ± 0.06 kg). In summary, PG 600 accelerated the onset of estrus in sows weaned during the summer. Sows mated during the induced estrus, however, tended to have a lower farrowing rate and farrowed lighter pigs than control sows inseminated during a natural estrus occurring within 7 d after weaning.

Farrowing induction with a combination of prostaglandin F 2α and a peripherally acting α 2-Adrenergic agonist AGN 190851 and a combination of prostaglandin F 2α and oxytocin

We studied the effect of prostaglandin (PG) F 2α-AGN 190851 on farrowing induction and compared it with that of PGF 2α-oxytocin. Eighty crossbred, multiparous sows were randomly assigned to the following 4 treatment groups of 20 sows each: 1) control, saline-saline; 2) PGF 2α (10 mg/sow)-oxytocin (30 IU/sow); 3) PGF 2α (10 mg/sow)-AGN 190851 (0.06 mg/kg); and 4) PGF 2α (10 mg/sow)-AGN 190851 (0.1 mg/kg). Either PGF 2α or saline was administered intramuscularly on Day 111 of gestation at 11:30 h; AGN 190851, oxytocin or saline was administered intramuscularly 20 h after the first injection. The PGF 2α-AGN 190851 (0.1 mg/kg) treated sows had the shortest mean farrowing interval (2.1 ± 1.6 h, mean ± SD) compared with the remaining treatment groups (control: 67.1 ± 26.2 h; PGF 2α-oxytocin: 5.6 ± 6.7 h; PGF 2α-AGN 190851 [0.06 mg/kg]: 3.0 ± 2.8 h). Duration of farrowing, litter size, litter weight and interval from weaning to first estrus in sows were not significantly changed by these treatments. The PGF 2α-oxytocin group had a significantly higher stillbirth rate than the control group, whereas the PGF 2α-AGN 190851 (0.1 mg/kg) group had the lowest number of pigs born dead and stillbirth rate among the 4 treatment groups. These results suggested that the PGF 2α-AGN 190851 combination can be used as an alternative method to PGF 2α-oxytocin for synchronizing farrowing.

OESTRUS (STANDING RESPONSE FOR BOAR and MAN) and OVULATION IN SOWS

Reproduction in Domestic AnimalsVolume 31, Issue 2 p. 293-294 OESTRUS (STANDING RESPONSE FOR BOAR and MAN) and OVULATION IN SOWS N.M. Soede, N.M. Soede Department of Animal Husbandry, Agricultural University, Wageningen, The NetherlandsSearch for more papers by this authorC.C.H. Wetzels, C.C.H. Wetzels Department of Animal Husbandry, Agricultural University, Wageningen, The NetherlandsSearch for more papers by this authorB. Kemp, B. Kemp Department of Animal Husbandry, Agricultural University, Wageningen, The NetherlandsSearch for more papers by this author N.M. Soede, N.M. Soede Department of Animal Husbandry, Agricultural University, Wageningen, The NetherlandsSearch for more papers by this authorC.C.H. Wetzels, C.C.H. Wetzels Department of Animal Husbandry, Agricultural University, Wageningen, The NetherlandsSearch for more papers by this authorB. Kemp, B. Kemp Department of Animal Husbandry, Agricultural University, Wageningen, The NetherlandsSearch for more papers by this author First published: September 1996 https://doi.org/10.1111/j.1439-0531.1996.tb00064.xCitations: 3AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume31, Issue2September 1996Pages 293-294 RelatedInformation