Jinhyeon Yun

Benefits of Prepartum Nest-building Behaviour on Parturition and Lactation in Sows — A Review

It is well known that prepartum sows have an innate motivation to build a nest before parturition. Under commercial conditions, however, the farrowing crate, which is widely used in modern pig husbandry, inhibits this innate behaviour through the lack of space, materials, or both. Thus, restriction of nest-building behaviour could generate increased stress, resulting in a decrease in maternal endogenous hormones. Hence, it could lead to detrimental effects on farrowing and lactating performance. Here we review interactions between prepartum nest-building behaviour, stress and maternal endogenous hormone levels, and discuss their effects on parturition, lactation, and welfare of sows and offspring.

Serial transvaginal ultrasound-guided biopsy of the porcine corpus luteum in vivo

The aims of the present study was to develop and describe a transvaginal ultrasound-guided biopsy method for luteal tissue in the porcine and to evaluate the effects of the method on the reproductive tract, ovarian status and pregnancy status. Biopsies were performed in four multiparous sows on Days 9 and 15 of three consecutive oestrous cycles; the size and histological composition of the samples obtained were evaluated and the reproductive tract of the sows was monitored. Furthermore, biopsies were performed in 26 multiparous sows on Days 10 and 13 after insemination, and the pregnancy rate, gestation length and subsequent litter size were evaluated. RNA was extracted from the samples obtained and the quality and quantity were determined. Altogether, 76 biopsies were performed and 38 samples were obtained. Compared with sows from which no samples were obtained (n = 6), sows from which one or more samples were obtained (n = 24) were older (parity 5.0 ± 2.8 vs 2.2 ± 0.4, mean ± s.d.), heavier (290 ± 26 vs 244 ± 27 kg) and had higher back fat (11.4 ± 2.7 vs 6.4 ± 2.5 mm; P < 0.05 for all). No effect of the biopsies (P > 0.05) was observed on the cyclicity and reproductive organs of the sows, or on corpus luteum diameter on Day 13 (8.9 ± 1.0 vs 9.2 ± 1.1 mm), pregnancy rate (95% vs 96%), gestation length (115 ± 1 vs 115 ± 1 days) and subsequent litter size (12.7 ± 2.5 vs 13.3 ± 2.8) between sows from which samples were obtained and those from which no samples were obtained. The samples obtained had a diameter of 1 mm and contained heterogeneous tissue with various cell types. The RNA quantity was 520 ± 160 µg per sample and the RNA integrity number was 8.5 ± 1.0. In conclusion, an ultrasound-guided biopsy method for ovarian tissue, which can be used for gene expression studies, was established in the porcine. No effect on corpus luteum function was found.

Predicting farrowing of sows housed in crates and pens using accelerometers and CUSUM charts

Accelerometer collar to measure the activity in sows before farrowing.Used a dynamic linear model to extract trend from data with diurnal components.Used a CUSUM chart to detect a raise in activity.A single model to detect approaching farrowing in both pens and crates. Piglet mortality is a continuing problem in modern pig production. It is high especially during the first few days after birth and can be reduced by supervision of farrowing.There is currently a trend to move towards housing without crates due to animal welfare concerns. Thus, automatic systems that can predict farrowing equally well in different housing systems would have wider applicability than ones developed for crated systems only. A method that works with same parameters in different housing systems would be easier to maintain and reuse in different conditions. The aim of this study was to develop a new accelerometer based system to measure sow activity before farrowing. This data was then used to build a model to predict the approach of farrowing, based on increased activity, within 24h before the start of farrowing.We used a wireless 3D accelerometer to measure the activity of sows in order to detect farrowing. The accelerometer collars were attached to neck collars of 29 sows farrowing in crates and 33 sows farrowing in pens. We expected sows in pens to show higher activity, but a similar rise in the level.We used a single model to detect farrowing in both crates and pens. A dynamic linear model was used to model the activity of the sows before farrowing and to extract trend component from seasonal components and a CUSUM chart was used to detect activity increase.The model detected a rise in activity on average 13ź4.8h (meanźstandard deviation) before farrowing in sows housed in crates and pens with sensitivity of 96.7% and specificity of 100%. The fact that we were able to use a single model with a constant set of parameters gives indication that the method has potential to become a robust indicator of farrowing in different housing systems, even though pre-farrowing activity was higher in sows housed in pens than in crates.

The effects of ovarian biopsy and blood sampling methods on salivary cortisol and behaviour in sows

In reproductive physiology research, experimental animals are often subjected to stressful procedures, including blood sampling and biopsy. In this present study, presence of pain or distress induced by four different procedures was examined using a measurement of salivary cortisol levels and activity observations in sows. The treatments were: 1) PAL: The ovary was palpated through the rectum without snaring, 2) TUB: transvaginal ultrasound-guided biopsy of the ovary was conducted without snaring, 3) SNA: a soft rope snare was placed around the maxilla, 4) CAT: A soft rope snare was placed around the maxilla, and an intravenous catheter was inserted through the ear vein of the sows. Activities, social cohesion and other pain-related behaviour, and salivary cortisol concentrations were recorded. Salivary cortisol concentrations in CAT sows increased in response to the procedure (P<0.05), whereas the other treatments did not trigger a significant response. The CAT sows had higher cortisol concentrations than the other groups for 10min after initiation of the procedures (P<0.01), and they maintained higher cortisol levels than the PAL and TUB groups 15min post-treatment (P<0.05). Furthermore, the CAT sows showed the highest frequency of head shaking (P<0.001) and trembling behaviour (P<0.05) during the 1h post-treatment. Summarizing, the catheterization procedure might induce a short-term pain or stress response during and after the procedure in terms of pain-related behaviour and salivary cortisol status. We suggest that TUB might not cause appreciable pain or distress.

The effects of amoxicillin treatment of newborn piglets on the prevalence of hernias and abscesses, growth and ampicillin resistance of intestinal coliform bacteria in weaned pigs

This study investigated the effects of a single amoxicillin treatment of newborn piglets on the prevalence of hernias and abscesses until the age of nine weeks. We also studied whether the treatment was associated with growth and mortality, the need for treatment of other diseases, the proportions of ampicillin resistant coliforms and antimicrobial resistance patterns of intestinal Escherichia coli (E. coli). A total of 7156 piglets, from approximately 480 litters, were divided into two treatment groups: ANT (N = 3661) and CON (N = 3495), where piglets were treated with or without a single intramuscular injection of 75 mg amoxicillin one day after birth, respectively. The umbilical and inguinal areas of weaned pigs were palpated at four and nine weeks of age. At the same time, altogether 124 pigs with hernias or abscesses and 820 non-defective pigs from three pens per batch were weighed individually. Mortality and the need to treat piglets for other diseases were recorded. Piglet faecal samples were collected from three areas of the floors of each pen at four weeks of age. The prevalence of umbilical hernias or abscesses did not differ between the groups at four weeks of age, but it was higher in the CON group than in the ANT group at nine weeks of age (2.3% vs. 0.7%, P < 0.05). Numbers of inguinal hernias and abscesses did not differ between the groups at four or nine weeks of age. The ANT group, when it compared with the CON group, increased the weight gain between four and nine weeks of age (LS means ± SE; 497.5 g/d ± 5.0 vs. 475.3 g/d ± 4.9, P < 0.01), and decreased piglet mortality (19.5% ± 1.0 vs. 6.9% ± 1.0, P < 0.05) and the need to treat the piglets for leg problems (3.4% ± 0.3 vs. 1.9% ± 0.3%, P < 0.01) but not for other diseases by the age of four weeks. The proportion of ampicillin resistant intestinal coliform bacteria and the resistance patterns of the E. coli isolates were not different between the ANT and CON groups. In conclusion, our results showed that the amoxicillin treatment of new-born piglets produced statistically significant effect in some of the parameters studied. However, as these effects were only minor, we did not find grounds to recommend preventive antibiotic treatment. Further, continuous antimicrobial treatment of newborn piglets could negatively influence the development of the normal microbiota of the piglet and promote selection of antimicrobial resistance genes in herds. Therefore we suggest rejection of the use of routine administration of antimicrobial agents at birth.

Image Quality Assessment and Outliers Filtering in an Image-Based Animal Supervision System

This paper presents a probabilistic framework for the image quality assessment (QA), and filtering of outliers, in an image-based animal supervision system (asup). The proposed framework recognizes asups imperfect frames in two stages. The first stage deals with the similarity analysis of the same-class distributions. The objective of this stage is to maximize the separability measures by defining a set of similarity indicators (SI) under the condition that the number of permissible values for them is restricted to be relatively low. The second stage, namely faulty frame recognition (FFR), deals with asups QA training and real-time quality assessment (RTQS). In RTQS, decisions are made based on a real-time quality assessment mechanism such that the majority of the defected frames are removed from the consecutive sub routines that calculate the movements. The underlying approach consists of a set of SI indexes employed in a simple Bayesian inference model. The results confirm that a significant amount of defected frames can be efficiently classified by this approach. The performance of the proposed technique is demonstrated by the classification on a cross-validation set of mixed high and low quality frames. The classification shows a true positive rate of 88.6% while the false negative rate is only about 2.5%.