Monitoring of sows’ health is the key to preventing and controlling diseases in sows, and it guarantees optimal rearing conditions for piglets. The aim of this study was to investigate the relationship between the health status of sows shortly after parturition, and to analyze thermographic images of the mammary gland and the sows’ performance. Clinical examination of a total of 513 db.Viktoria hybrid sows was bundled individually using a modified score system. According to this, animals were divided into three health classes: healthy, clinically suspicious, and diseased. Simultaneously, the mammary glands were investigated by infrared thermography. Total born piglets (TBP), number of piglets born alive (NBA), and the daily weight gain of the piglets were significantly lower in the diseased group (p < 0.05). Regarding the results of the thermographic images of the mammary gland, significantly higher mean value of the warmest pixels was found in the diseased group (38.3 °C ± 0.57), while the significantly lowest value was reported in the healthy group (37.2 °C ± 0.54; p < 0.05). The results of this study show that thermography of the mammary gland at birth contains information that can help to identify diseased animals whose disease has negative effects on their piglets.

Colostrum is the primary source of nutrients for newborn piglets, significantly influencing their growth, health and survival. This study examines the relationship between sow litter weight gain and the fatty acid composition of colostrum, including crude protein, lactose, calculated gross energy and total solids. The n-6:n-3 fatty acid ratio was higher in low-performing sows (p < 0.05), suggesting that a lower ratio, associated with higher n-3 fatty acid content, may positively impact litter weight gain. Specific fatty acids such as myristic acid (C14:0), pentadecanoic acid (C15:0), palmitic acid (C16:0), palmitoleic acid (C16:1), margaric acid (C17:0), elaidic acid (C18:1n9t), linoleic acid (C18:2n6c), α-linolenic acid (C18:3n3), behenic acid (C22:0), docosadienoic acid (C22:2) and eicosapentaenoic acid (C20:5n3) were also found in lower concentrations in the colostrum of low-performing sows (p < 0.05). The study suggests that the content of n-3 fatty acids and perhaps the n-6:n-3 ratio of the colostrum and the content of some special fatty acids could serve as a selection criterion for improving litter performance in the future.

The present study aimed to adjust the previously developed milk score (MS) to increase on-farm practicability in sows’ foster performance assessment. A total of 1,728 litters and thereof 574 litters from sows with at least two consecutive parities were used. The network analysis demonstrated that 65.80% of sows achieved the same performance group in the subsequent parity again. To increase the MS applicability, a linear regression model was developed, omitting a second piglet weighing during the suckling period and using the mean litter birth weight. This model can predict sow performance with 81.66% accuracy. High-performing sows are characterized as sows with the significantly highest relative weight loss during lactation (P < 0.05). The MS only selects the best-performing old parity sows with high piglet weights and low stillbirth piglets for the subsequent parity. Thus, the application might help to increase sow longevity and the litter quality of the herd. In contrast to previously developed sow replacement models, smaller litter sizes, lower piglet mortality, and higher piglet weights are better assessed in the adjusted MS, which reduces adverse animal welfare effects caused by larger litter sizes. The adjusted MS provides a data-based and welfare-oriented performance assessment that farmers can use to support their farm-specific replacement decisions.

Colostrum is the main source of nutrients and proteins for newborn piglets. To give each piglet the best possible start in life, it is necessary to evaluate the colostrum according to quality. This has to be done by analysing the components, as component composition is a main quality parameter. To achieve this aim, in this study, the content of total solids, crude protein and 24 fatty acids in colostrum samples was analysed. The colostrum samples from 334 sows were classified according to the parity of the donor sow. Parity group 1 contained parity 1 and 2 sows ( n  = 93), parity group 2 contained parity 3 and 4 sows ( n = 109), parity group 3 contained parity 5 and 6 sows ( n = 61) and parity group 4 contained sows in parity 7 and higher ( n = 71). In addition, 187 sows were investigated clinically within 2 days after farrowing and divided into three groups according to their health status with regard to postpartum dysgalactia syndrome (PDS) (healthy [ n = 83], clinically suspicious [ n = 74] and diseased sows [ n = 30]). In this way, it was tested whether puerperal diseases affected the content of fatty acids, crude protein and total solids. Only a few of the colostrum constituents were directly linked to the health of the sows regarding PDS after farrowing. When comparing the contents of the different fatty acids in % of total fatty acids, the content of C18:0 in the colostrum of clinically suspicious sows was higher than in the colostrum of sows without PDS. The colostrum of sows without PDS had a higher content of C18:2n6c and C18:3n3 than the colostrum of clinically suspicious sows. Furthermore, the colostrum of PDS‐diseased sows had a higher proportion of C20:2 than that of clinically suspicious sows. With regard to C24:1, the colostrum of sows without PDS had a higher proportion than that of PDS‐diseased sows. In contrast, the parity group of the sows affected the quantity of 15 of the 24 analysed fatty acids. With regard to the proportion of the colostrum constituents in the whole colostrum, the colostrum of younger sows up to the 4th parity compared to older sows often had higher proportions of fatty acids (16 out of 24 parameters with significant differences), especially n‐3 (C20:5n3, C22:6n3, C18:3n3) compared with n‐6 (C18:2n6c, C18:3n6, C20:3n6, C20:4n6) and n3:n6 ratio (parity group 1: 14.6; parity group 2: 15.1; parity group 3: 15.4 and parity group 4: 15.5). No differences in total solids or crude protein were observed between the health groups regarding PDS or among the parity groups. In summary, there was rarely any link between health status regarding PDS and colostrum constituents, as opposed to a more consistent link between parity groups and colostrum constituents.