Application of liquid chromatography coupled to high-resolution mass spectrometry to measure urinary cortisol in loose housed sows

Cortisol is the most common physiological parameter used to measure welfare in pigs. In field studies evaluating stress in individual pigs which are group housed, the collection of spontaneously voided urine is practical. The purpose of the study was to apply a liquid chromatography coupled to high-resolution mass spectrometry approach to observe the patterns of diurnal urinary cortisol excretion among loose sows of three herds. We applied the analytical method in spontaneously voided urine of thirty, repeatedly sampled within a day, multiparous sows of three Greek herds. We found the level of urinary cortisol being highest before morning feeding [geometric mean of urinary cortisol to creatinine ratio being 2.72 (95% confidence interval: 1.17, 6.30), 5.65 (3.15, 10.14) and 2.60 (1.50, 4.50) in sows of herds A, B, and C, respectively] and lowest at 19: 00 h [0.56 (0.27, 1.18), 1.24 (0.74, 2.07), 0.88 (0.55, 1.44)]. However, the patterns of diurnal urinary cortisol excretion appeared different among herds

Effect of diet supplementation with chelated zinc, copper and manganese on hoof lesions of loose housed sows

Background: Hoof lesions are very common among sows and have been associated with lameness, early removal and compromised welfare and productivity. Although housing conditions and management can have an external effect on hoof health status, the role of trace mineral intake is vital in developing hoof structure and integrity. Therefore, the objective of this study was to investigate the effect of a diet supplemented with organic complexes of trace minerals (Zn, Cu, Mn), partly substituting their inorganic form, on hoof lesions of sows in three Greek swine herds. Results: A total of 518 sows were initially examined for hoof lesions and their respective severity was scored. For each hoof, the length of toes and dew claws were evaluated and five anatomical hoof sites, the heel, the sole, the white line, the wall and the coronary band, were examined for lesions. Subsequently, the same sows were re-scored after one or two gestations on diets supplemented with organic trace minerals, partly substituting their inorganic salt form (organic form of Zn 45 ppm, Cu 14 ppm and Mn 25 ppm of the total 125 ppm of Zn, 15 ppm of Cu and 40 ppm of Mn, respectively). The odds of the higher versus the lower lesion scores were significantly lower after than before the inclusion of the organic minerals in sows' diet, for each of the considered foot sites with the exception of the coronary band, with a distinct effect according to foot location. Specifically, on rear feet the improvement of hoof lesions was either smaller (for heel, sole and wall) than on front feet or not significant (for white line, toe and dew claw length). Additionally, for each foot site and herd examined, after the inclusion of the organic minerals, there were more sows with either the same or lower lesion score, with the exception of the toe and the dew claw length in one of the herds. Conclusions: Within the specific conditions in the three studied herds, our findings highlight the role of chelated trace minerals in sows' hoof health, suggesting an applicable and rewarding intervention to prevent hoof lesions. © The Author(s). 2018

Effect of increased dietary fiber on hoof lesions of loose housed sows

Loose dry sow housing became mandatory in the European Union from January 2013 onwards. One of the major causes of injuries to sows' hooves and associated lameness is fighting on concrete/slatted flooring at grouping. Previous studies observed that in sows submitted to feed restriction, feed supplemented with dietary fiber reduced the time spent in the standing position and increased the time spent in the lying position. Therefore, we investigated the effect of increased levels of dietary fiber (7.2-7.5% crude fiber/kg dry matter) on the severity of hoof lesions of group housed sows in three Greek swine herds. The feet of 596 sows were initially examined for lesions upon their entry to the lactation facilities. Lesions scored included hoof hyperkeratinization, erosions or cracks and toe and dew claws overgrowths. When exiting the farrowing facilities they were offered recipes with increased dietary fiber throughout one or two subsequent gestations. Thirty-eight percent were re-examined for feet lesions during the first and sixty-two percent during the second lactation after initial examination. The proportion of sows with at least one lesion on any foot, at first scoring, was more than 95% in all herds. The most frequently and severely affected sites were the heel and the elongated toes and dew claws. The increased dietary fiber had no effect on lesion severity on any of the hoof sites considered

Hoof lesions and lameness in sows in three Greek swine herds

Objectives: To characterize foot lesions, estimate their frequency and severity, and investigate their association with parity and lameness in three Greek farrow-to-finish swine herds. Materials and methods: The studied sows, which had been individually stalled during previous gestations, were examined for foot lesions upon entry into the lactation facilities. Lesions scored included heel hyperkeratinization, erosions or cracks, and toe and dew claw overgrowths. When exiting the farrowing facilities, the sows were observed while walking along an alley and their degree of lameness was scored. Results: The proportion of sows with at least one lesion on any foot was very high and similar among herds, with 121 of 125 (96.8%), 123 of 125 (98.4%), and 377 of 386 (97.7%) sows affected in herds A, B, and C, respectively. The most frequent lesions were those located on the heel, and overgrown toes and dew claws. For these sites, lesion severity increased with sow parity. The concurrent presence of lesions on more than one foot site, on the same or different feet or both, had a multiplicative effect on the likelihood of lameness. Implications: Under the conditions in the herds participating in this study, sow foot lesions are extremely common, with older sows more likely than younger sows to have lesions on the heel and overgrown toes and dew claws. The degree of lameness may be affected by a causal interface among foot lesions

Effect of sow diets supplementation with chelated trace minerals on their reproductive performance

Trace minerals are constituents of proteins and enzymes that are involved in a variety of metabolic processes, having functional implications in growth, development, reproduction and health. Chelated minerals, are minerals bound to organic ligands. usually amino acids, providing higher levels of bioavailability compared to conventional inorganic mineral sources. In the present study, we investigated the effect of partial substitution of inorganic mineral sources with chelated minerals in sows' diets, on three important reproductive parameters, the number of liveborn and weaned piglets and the wean-to-first service interval, in three Greek farrow-to-finish herds. Before initiation of the study the sows were on diets supplemented with 15 mg/kg feed Cu (from CuS04), 125 mg/kg Zn (from ZnO) and 40 mg/kg Mn (from MnO). After exiting the farrowing facilities they were ottered diets in which 93.3%, 36.0% and 62.5% of the supplemented Cu. Zn and Mn. respectively, originated from commercially available chelated minerals. For the last farrowing on inorganic minerals diet and the subsequent one or two (for 35.0% and 65.0% of the studied sows, respectively) on chelated minerals, each sow's reproductive data (total number of parities, number of liveborn and weaned piglets and wean-to-first service interval) were recorded. The reproductive parameters, before and after the supplementation with chelated minerals, were compared in two mixed-effect linear regression models, lor the number of liveborn and weaned piglets, and in a zero inflated negative binomial model for the weaning-to-first service interval. There was an improvement of the mean number ofliveborn piglets after partial substitution of inorganic source of minerals with chelated minerals by almost half a piglet (P=0.015). whereas there was no effect on the total number of weaned piglets (P=0.15) and the wean-to-first service interval (P=0.65). The increase in the number ofliveborn piglets may be directly attributed to improved embryo survival due to increased bioavailability of the organic minerals or indirectly to the beneficial effect of chelated minerals on sows' hoof health, locomotor ability, feed intake and body condition

Associations between claw lesions and reproductive performance of sows in three Greek herds

Claw lesions, which are nowadays very common in sows, are associated with a high risk of early culling and compromised welfare. In this study, we investigated the associations between the severity of claw lesions and three of the most important reproductive indicators, the number of live-born and weaned piglets and the wean-to-first service interval in three Greek farrow-to-finish herds. All studied sows were individually housed during their previous gestations. Sows were examined for lesions, which were scored on a severity scale, on several anatomical sites of the claws, before farrowing. Data on the examined reproductive indicators were retrieved from productivity databases of the herds. Because scoring of lesions on several claw sites resulted in many correlated variables for each sow examined, we employed factor analysis to create a smaller set of uncorrelated variables (factors) which contained all the information in the original variables and produced the corresponding factor scores. The number of live-born and weaned piglets was associated with the produced factor scores in two multivariable linear regression models, whereas the possible associations between the wean-to-first service interval and the factor scores was modelled with the use of zero-inflated negative binomial regression. The number of live-born piglets was negatively associated with factor scores representing lesions on heel (P <= 0.001) and sole of front feet (P = 0.019). The number of weaned piglets was also negatively associated with factor scores representing lesions on heel (P = 0.003) of any foot, on sole of front feet (P = 0.001) and on white line, sole and wall of rear feet (P = 0.008), while the wean-to-first service interval was associated with factor scores representing lesions on heel of any foot (P = 0.02), on sole of front feet (P = 0.02) and of dew claw length of front feet (P = 0.009). Our results indicate that combinations of lesions on the dorsal and ventral part of the claws, negatively affected the reproduction parameters considered, emphasising the importance of general improvement of feet health

Pathological evaluation of claw lesions in culled sows from a Greek herd

Objectives: To characterize macroscopic claw lesions of culled sows, describe the histologic characteristics observed in the laminar corium and investigate their associations with lesion severity, and compare the morphometric characteristics of horn tubules among claws according to lesion severity. Materials and methods: One front and the opposite rear foot from 74 culled sows of one herd were examined for lesions. From each claw, a tissue sample consisting of dermis and epidermis was examined histologically for changes suggesting laminitis. Slices from the lateral claws of the rear feet of 48 sows were examined morphometrically to evaluate the density and size of horn tubules. Results: The most frequent lesions were those located on the heel, wall, and white line, with 146 (49.3%), 94 (31.8%), and 81 (27.4%) affected claws, respectively, among the 296 examined. Lamellar hyperplasia was the most frequently recorded characteristic in the epidermis of 87 of 296 claws (29.4%) in 51 of the 74 examined sows (68.9%). The total lesion score of the claw was higher (P > .001) when lamellar hyperplasia was recorded than when no histologic change was recorded. The density of horn tubules was lowest (P = .018) and the size was largest (P > .001) among animals with severe wall lesions, compared to those without wall lesions. Implications: The histologic changes observed in the dermis and epidermis of the sows' claws have been described in cases of equine and bovine laminitis. Sow laminitis may frequently occur, causing production of low quality hoof horn