Pentachlorophenol affects doxycycline and tetracycline resistance genes in soil by altering microbial structure.

Tetracycline antibiotics play a vital role in animal husbandry, primarily employed to uphold the health of livestock and poultry. Consequently, when manure is reintegrated into farmland, tetracycline antibiotics can persist in the soil. Simultaneously, to ensure optimal crop production, organochlorine pesticides (OCPs) are frequently applied to farmland. The coexistence of tetracycline antibiotics and OCPs in soil may lead to an increased risk of transmission of tetracycline resistance genes (TRGs). Nevertheless, the precise mechanism underlying the effects of OCPs on tetracycline antibiotics and TRGs remains elusive. In this study, we aimed to investigate the effects of OCPs on soil tetracycline antibiotics and TRGs using different concentrations of doxycycline (DOX) and pentachlorophenol (PCP). The findings indicate that PCP and DOX mutually impede their degradation in soil. Furthermore, our investigation identifies Sphingomonas and Bacillus as potential pivotal microorganisms influencing the reciprocal inhibition of PCP and DOX. Additionally, it is observed that the concurrent presence of PCP and DOX could impede each other's degradation by elevating soil conductivity. Furthermore, we observed that a high concentration of PCP (10.7 mg/kg) reduced the content of efflux pump tetA, ribosome protective protein tetM, tetQ, and passivating enzyme tetX. In contrast, a low PCP concentration (6.4 mg/kg) only reduced the content of ribosome protective protein tetQ. This suggests that PCP may reduce the relative abundance of TRGs by altering the soil microbial community structure and inhibiting the potential host bacteria of TRGs. These findings have significant implications in understanding the combined pollution of veterinary antibiotics and OCPs. By shedding light on the interactions between these compounds and their impact on microbial communities, this study provides a theoretical basis for developing strategies to manage and mitigate their environmental impact, and may give some information regarding the sustainable use of antibiotics and pesticides to ensure the long-term health and productivity of agricultural systems.

A Systematic Review of Genomic Regions and Candidate Genes Underlying Behavioral Traits in Farmed Mammals and Their Link with Human Disorders.

The main objectives of this study were to perform a systematic review of genomic regions associated with various behavioral traits in the main farmed mammals and identify key candidate genes and potential causal mutations by contrasting the frequency of polymorphisms in cattle breeds with divergent behavioral traits (based on a subjective clustering approach). A total of 687 (cattle), 1391 (pigs), and 148 (sheep) genomic regions associated with 37 (cattle), 55 (pigs), and 22 (sheep) behavioral traits were identified in the literature. In total, 383, 317, and 15 genes overlap with genomic regions identified for cattle, pigs, and sheep, respectively. Six common genes (e.g., NR3C2, PITPNM3, RERG, SPNS3, U6, and ZFAT) were found for cattle and pigs. A combined gene-set of 634 human genes was produced through identified homologous genes. A total of 313 out of 634 genes have previously been associated with behavioral, mental, and neurologic disorders (e.g., anxiety and schizophrenia) in humans. Additionally, a total of 491 candidate genes had at least one statistically significant polymorphism (p-value < 0.05). Out of those, 110 genes were defined as having polymorphic regions differing in greater than 50% of exon regions. Therefore, conserved genomic regions controlling behavior were found across farmed mammal species and humans.

Contactless Video-Based Heart Rate Monitoring of a Resting and an Anesthetized Pig.

Heart rate (HR) is a vital bio-signal that is relatively easy to monitor with contact sensors and is related to a living organism's state of health, stress and well-being. The objective of this study was to develop an algorithm to extract HR (in beats per minute) of an anesthetized and a resting pig from raw video data as a first step towards continuous monitoring of health and welfare of pigs. Data were obtained from two experiments, wherein the pigs were video recorded whilst wearing an electrocardiography (ECG) monitoring system as gold standard (GS). In order to develop the algorithm, this study used a bandpass filter to remove noise. Then, a short-time Fourier transform (STFT) method was tested by evaluating different window sizes and window functions to accurately identify the HR. The resulting algorithm was first tested on videos of an anesthetized pig that maintained a relatively constant HR. The GS HR measurements for the anesthetized pig had a mean value of 71.76 bpm and standard deviation (SD) of 3.57 bpm. The developed algorithm had 2.33 bpm in mean absolute error (MAE), 3.09 bpm in root mean square error (RMSE) and 67% in HR estimation error below 3.5 bpm. The sensitivity of the algorithm was then tested on the video of a non-anaesthetized resting pig, as an animal in this state has more fluctuations in HR than an anaesthetized pig, while motion artefacts are still minimized due to resting. The GS HR measurements for the resting pig had a mean value of 161.43 bpm and SD of 10.11 bpm. The video-extracted HR showed a performance of 4.69 bpm in MAE, 6.43 bpm in RMSE and 57% in . The results showed that HR monitoring using only the green channel of the video signal was better than using three color channels, which reduces computing complexity. By comparing different regions of interest (ROI), the region around the abdomen was found physiologically better than the face and front leg parts. In summary, the developed algorithm based on video data has potential to be used for contactless HR measurement and may be applied on resting pigs for real-time monitoring of their health and welfare status, which is of significant interest for veterinarians and farmers.

Corrigendum: COVID-19 Effects on Livestock Production: A One Welfare Issue.

[This corrects the article DOI: 10.3389/fvets.2020.585787.].

In utero heat stress alters the postnatal innate immune response of pigs.

The effects of in utero heat stress (IUHS) range from decreased growth performance to altered behavior, but the long-term impact of IUHS on postnatal innate immune function in pigs is unknown. Therefore, the study objective was to determine the effects of early gestation IUHS on the immune, metabolic, and stress response of pigs subjected to an 8 hr lipopolysaccharide (LPS) challenge during postnatal life. Twenty-four pregnant gilts were exposed to thermoneutral (TN; n = 12; 17.5 ± 2.1 °C) or heat stress (HS; n = 12; cyclic 26 to 36 °C) conditions from days 6 to 59 of gestation, and then TN conditions (20.9 ± 2.3 °C) from day 60 of gestation to farrowing. At 12 wk of age, 16 IUHS and 16 in utero thermoneutral (IUTN) pigs were selected, balanced by sex and given an intravenous injection of LPS (2 µg/kg BW mixed with sterile saline [SAL] and injected at 2 µL/kg BW) or SAL (2 µL/kg BW). Body temperature was monitored every 30 min, and blood was obtained at 0, 1, 2, 3, 4, 6, and 8 hr following the LPS challenge. Blood samples were analyzed for glucose, insulin, non-esterified fatty acids (NEFA), cortisol, and cytokine concentrations. In addition, white blood cell counts were determined at 0 and 4 hr. Hour 0 data were used as covariates. Body temperature was increased (P < 0.01) in LPS (40.88 ± 0.08 °C) vs. SAL (39.83 ± 0.08 °C) pigs. Eosinophils tended to be decreased overall (P = 0.09; 43.9%) in IUHS vs. IUTN pigs. Glucose concentrations were reduced overall (P = 0.05; 5.9%) in IUHS vs. IUTN pigs. The NEFA concentrations tended to be greater (P = 0.07; 143.4%) in IUHS-LPS pigs compared with all other treatments, and IUTN-LPS pigs tended to have greater (127.4%) circulating NEFA concentrations compared with IUTN-SAL and IUHS-SAL pigs. Cortisol was increased (P = 0.04) in IUHS-LPS compared with IUTN-LPS pigs at 3 hr (21.5%) and 4 hr (64.3%). At 1 hr, tumor necrosis factor α was increased (P = 0.01; 115.1%) in IUHS-LPS compared with IUTN-LPS pigs. Overall, interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) were greater (P < 0.04; 281.3% and 297.8%, respectively) in IUHS-LPS pigs compared with all other treatments, and IUTN-LPS pigs had increased IL-1ß and IL-6 concentrations compared with IUTN-SAL and IUHS-SAL pigs. In summary, IUHS altered the postnatal cytokine, metabolic, and physiological stress response of pigs during postnatal life, which may have negative implications toward the innate immune response of IUHS pigs to pathogens.

COVID-19 Effects on Livestock Production: A One Welfare Issue.

The COVID-19 pandemic highlights that we exist in a global community. From a single city, it spread to 188 countries across the world and infected 30 million people by September 18, 2020. Decades of modeling pandemics predicted potential consequences, but COVID-19's impact on the food supply chain, and specifically livestock production was unexpected. Clusters of cases among workers in meat processing plants evolved quickly to affect human, animal, and environmental welfare in several countries. In processing plants, the hygiene focus is on product quality and food safety. Because of their close proximity to one another, COVID-19 spread rapidly between workers and the lack of sick leave and health insurance likely resulted in workers continuing to work when infectious. In the United States (U.S.) many processing plants shut down when they identified major outbreaks, putting pressure especially on pig and poultry industries. At one point, there was a 45% reduction in pig processing capacity meaning about 250,000 pigs per day were not slaughtered. This resulted in longer transport distances to plants in operation with extra capacity, but also to crowding of animals on farm. Producers were encouraged to slow growth rates, but some had to cull animals on farm in ways that likely included suffering and caused considerable upset to owners and workers. Carcass disposal was also associated with potential biosecurity risks and detrimental effects on the environment. Hence, this is a One Welfare issue, affecting human, animal, and environmental welfare and highlighting the fragility of intensive, high-throughput livestock production systems. This model needs to be re-shaped to include the animal, human, and environmental elements across the farm to fork chain. Such a One Welfare approach will ensure that food production systems are resilient, flexible, and fair in the face of future challenges.

Large-Scale Phenotyping of Livestock Welfare in Commercial Production Systems: A New Frontier in Animal Breeding.

Genomic breeding programs have been paramount in improving the rates of genetic progress of productive efficiency traits in livestock. Such improvement has been accompanied by the intensification of production systems, use of a wider range of precision technologies in routine management practices, and high-throughput phenotyping. Simultaneously, a greater public awareness of animal welfare has influenced livestock producers to place more emphasis on welfare relative to production traits. Therefore, management practices and breeding technologies in livestock have been developed in recent years to enhance animal welfare. In particular, genomic selection can be used to improve livestock social behavior, resilience to disease and other stress factors, and ease habituation to production system changes. The main requirements for including novel behavioral and welfare traits in genomic breeding schemes are: (1) to identify traits that represent the biological mechanisms of the industry breeding goals; (2) the availability of individual phenotypic records measured on a large number of animals (ideally with genomic information); (3) the derived traits are heritable, biologically meaningful, repeatable, and (ideally) not highly correlated with other traits already included in the selection indexes; and (4) genomic information is available for a large number of individuals (or genetically close individuals) with phenotypic records. In this review, we (1) describe a potential route for development of novel welfare indicator traits (using ideal phenotypes) for both genetic and genomic selection schemes; (2) summarize key indicator variables of livestock behavior and welfare, including a detailed assessment of thermal stress in livestock; (3) describe the primary statistical and bioinformatic methods available for large-scale data analyses of animal welfare; and (4) identify major advancements, challenges, and opportunities to generate high-throughput and large-scale datasets to enable genetic and genomic selection for improved welfare in livestock. A wide variety of novel welfare indicator traits can be derived from information captured by modern technology such as sensors, automatic feeding systems, milking robots, activity monitors, video cameras, and indirect biomarkers at the cellular and physiological levels. The development of novel traits coupled with genomic selection schemes for improved welfare in livestock can be feasible and optimized based on recently developed (or developing) technologies. Efficient implementation of genetic and genomic selection for improved animal welfare also requires the integration of a multitude of scientific fields such as cell and molecular biology, neuroscience, immunology, stress physiology, computer science, engineering, quantitative genomics, and bioinformatics.

Evaluation and mitigation of the effects of in utero heat stress on piglet growth performance, postabsorptive metabolism, and stress response following weaning and transport.

In utero heat stress (IUHS) increases the energy requirements of pigs during postnatal life, and this may compound weaning and transport stress. The study objective was to evaluate and mitigate the negative effects of IUHS following weaning and transport through the provision of a nutrient-dense (ND) nursery diet formulated to meet the greater energy requirements of IUHS pigs during the first 14 d postweaning and transport. Twenty-four pregnant gilts were exposed to thermoneutral (TN; n = 12; 17.5 ± 2.1 °C) or heat stress (HS; n = 12; cycling 26 to 36 °C) conditions for the first half of gestation (day 6 to 59) and then TN conditions (20.9 ± 2.3 °C) until farrowing. Nine TN gilts and 12 HS gilts produced litters. At weaning (16.2 ± 0.4 d), mixed-sex piglets (N = 160; 4.78 ± 0.15 kg body weight [BW]) were transported (loading + transport + unloading) for 11 h 40 min. Following transport, piglets were blocked into pens (n = 4 pigs/pen) by in utero and dietary treatments: in utero thermoneutral (IUTN) + control (C) diet (n = 10 pens), IUTN + ND (n = 10 pens), IUHS + C (n = 10 pens), and IUHS + ND (n = 10 pens). Treatment diets were fed from day 1 to 14 postweaning and transport (period 1), and the C diet was fed to all pigs from day 14 to 35 postweaning and transport (period 2). Production measures were taken in 7 d intervals to calculate average daily gain (ADG), average daily feed intake (ADFI), average daily net energy intake (ADEI), gain:feed, and gain:net energy intake. Blood samples were collected prior to transport, following transport, and on days 2, 7, 14, 28, and 35 postweaning and transport to analyze cortisol, glucose, insulin, and nonesterified fatty acids. Behavior was assessed through video-recording on days 3, 5, 8, 11, and 13 postweaning and transport. In period 1, ADG was reduced (P = 0.04; 20.0 g/d) in IUHS vs. IUTN pigs. Pigs fed ND diets had reduced ADFI (P = 0.02; 9.3%) compared with C diet-fed pigs during period 1, which resulted in similar ADEI (P = 0.23; 1,115 ± 35 kcal/d). During transport, cortisol was decreased (P = 0.03; 25.8%) in IUHS vs. IUTN pigs. On day 2, glucose was decreased (P = 0.01; 13.8%) in IUHS vs. IUTN pigs. No in utero treatment-related behavior differences were observed but lying was reduced (P = 0.03; 6.5%) and standing was increased (P = 0.04; 14.1%) in ND vs. C pigs overall. In summary, IUHS reduced growth performance in pigs following weaning and transport, and providing an ND diet did not rescue the lost performance.

Effect of Cornstalk Biochar Immobilized Bacteria on Ammonia Reduction in Laying Hen Manure Composting.

NH3 emission has become one of the key factors for aerobic composting of animal manure. It has been reported that adding microbial agents during aerobic composting can reduce NH3 emissions. However, environmental factors have a considerable influence on the activity and stability of the microbial agent. Therefore, this study used cornstalk biochar as carriers to find out the better biological immobilization method to examine the mitigation ability and mechanism of NH3 production from laying hen manure composting. The results from different immobilized methods showed that NH3 was reduced by 12.43%, 5.53%, 14.57%, and 22.61% in the cornstalk biochar group, free load bacteria group, mixed load bacteria group, and separate load bacteria group, respectively. Under the simulated composting condition, NH3 production was 46.52, 38.14, 39.08, and 30.81 g in the treatment of the control, mixed bacteria, cornstalk biochar, and cornstalk biochar separate load immobilized mixed bacteria, respectively. The cornstalk biochar separate load immobilized mixed bacteria treatment significantly reduced NH3 emission compared with the other treatments (p < 0.05). Compared with the control, adding cornstalk biochar immobilized mixed bacteria significantly decreased the electrical conductivity, water-soluble carbon, total nitrogen loss, and concentration of ammonium nitrogen (p < 0.05), and significantly increased the seed germination rate, total number of microorganisms, and relative abundance of lactic acid bacteria throughout the composting process (p < 0.05). Therefore, the reason for the low NH3 emission might be due not only to the adsorption of the cornstalk biochar but also because of the role of complex bacteria, which increases the relative abundance of lactic acid bacteria and promotes the acid production of lactic acid bacteria to reduce NH3 emissions. This result revealed the potential of using biological immobilization technology to reduce NH3 emissions during laying hen manure composting.

Effects of Three Distinct 2-Week Long Diet Strategies After Transport on Weaned Pigs' Short and Long-Term Welfare Markers, Behaviors, and Microbiota.

Alternative feed supplements have shown promising effects in terms of performance, but their effects on welfare have had little evaluation. In the present study, we aimed at evaluating the effect of diet supplementation on welfare indicators. A total of 246 piglets were weaned and transported for 12 h. After transport, they were assigned to one of 3 diets for a 14-day period: A-an antibiotic diet including chlortetracycline and tiamulin, NA-a control diet without any antibiotic or feed supplement, GLN-a diet including 0.20% L-glutamine. After the 14-day period, all piglets were fed the same diet. Tear staining was measured 11 times post-weaning (from d0 to 147). Skin lesions were counted before and after weaning (d-2, 2, and 36). Novel object tests (NOT) were done in groups 4 times post-weaning (d17, 47, 85, 111). Samples for 16S rRNA gene composition were collected prior to transport (d0), following the 14-day period (d14) and at the conclusion of the nursery phase (d34). The NA pigs appeared less interested in novel objects. On d17, they avoided the object less than A pigs (P < 0.05). They spent less time exploring the object on d85 and took longer to interact with the object on d111 than A and GLN pigs (P < 0.05). NA pigs also appeared more sensitive to environment and management. They had larger tear stains than GLN pigs on d84 and 110 (P < 0.05). On d2, NA pigs had more lesions than A and GLN (P < 0.01). In terms of microbiota composition, GLN had higher α-diversity than A and NA (P < 0.001). Differences between dietary treatments were absent at d0, were demonstrated at d14 and disappeared at d34. Pearson correlations between aggression, stress and anxiety indicators and bacterial populations were medium to high from 0.31 to 0.69. The results demonstrate that short-term feeding strategy can have both short- and long-term effects on behavior and welfare, that may partly be explained by changes in gut microbiota composition. Supplementation with GLN appears to confer similar benefits to dietary antibiotics and thus could be a viable alternative.

Effect of Floor Cooling on Behavior and Heart Rate of Late Lactation Sows Under Acute Heat Stress.

Much U.S. swine production is in Köppen climate types classified as "hot-summer humid continental" and "humid subtropical." As a result, farrowing sows are often exposed to temperatures above their upper critical temperature. This heat stress (HS) can affect sow welfare and productivity and have a negative economic impact. The study objective was to evaluate the impact of a cooling pad on sows' behavioral and heart rate responses to acute HS. Treatments were randomly allotted to ten multiparous sows to receive a constant cool water flow of 0.00 (CONTROL, n = 4), 0.25 (LOW, n = 2), 0.55 (MEDIUM, n = 2), or 0.85 (HIGH, n = 2) L/min for 100 min and replicated eight times, switching treatments so that each sow was exposed to each treatment. The cooling was initiated 1 h after the room reached 35°C for 100 min. Eating, drinking and nursing behaviors, postures, and heart rate were recorded before heating (Period 1), prior to cooling (Period 2), and during cooling (Period 3). There were no differences between LOW, MEDIUM, and HIGH flow rates for any periods on all behavioral and heart rate traits, so data were pooled (COOLED). There were no differences in any of the measures during Periods 1 and 2, except for the ratio of short term to long term heart rate variability (SD1:SD2) with higher values for CONTROL than COOLED sows in Period 2. During Period 3, CONTROL sows changed postures more frequently (11.5 ±1.6 vs. 5.1 ±1.6 changes per hour), spent more time drinker-pressing/drinking (4.4 ± 0.5 vs. 1.4 ± 0.4% of time), standing (6.6 ± 1.7 vs. 3.8 ± 1.6% of time), sitting (10.0 ± 1.2 vs. 4.0 ± 1.1), less time lying (83.0 ±1.8 vs. 92.0 ±1.7% of time), especially lying laterally (62.0 ± 5.6 vs. 75.0 ± 5.3% of time), than sows in all three cooling treatments (all P < 0.001). Heart rate during Period 3 was lower for COOLED sows compared to the CONTROL sows (100.2 ± 3.4 vs. 119.0 ± 4.0 beat per min, P < 0.001). Sows response to increased thermal load can be effectively reduced using water-cooled cooling pads, thereby improving sow comfort and welfare. The beneficial effects on behavior are noticeable from the lowest flow rate.

Mother's exercise during pregnancy programmes vasomotor function in adult offspring.

The intrauterine environment is influenced by maternal behaviour and programmes atherosclerotic disease susceptibility in offspring. The aim of this investigation was to test the hypothesis that mothers' exercise during pregnancy improves endothelial function in 3-, 5- and 9-month-old porcine offspring. The pregnant sows in the exercise group ran for an average of 39.35 ± 0.75 min at 4.81 ± 0.35 km h(-1) each day for 5 days per week for all but the last week of gestation. This induced a significant reduction in resting heart rate (exercised group, 89.3 ± 3.5 beats min(-1); sedentary group, 102.1 ± 3.1 beats min(-1); P < 0.05) but no significant differences in gestational weight gain (65.8 ± 2.1 versus 63.3 ± 1.9%). No significant effect on bradykinin-induced vasorelaxation with and without l-NAME was observed. A significant main effect was identified on sodium nitroprusside-induced vasorelaxation (P = 0.01), manifested by a reduced response in femoral arteries of all age groups from exercised-trained swine. Nitric oxide signalling was not affected by maternal exercise. Protein expression of MYPT1 was reduced in femoral arteries from 3-month-old offspring of exercised animals. A significant interaction was observed for PPP1R14A (P < 0.05) transcript abundance and its protein product CPI-17. In conclusion, pregnant swine are able to complete an exercise-training protocol that matches the current recommendations for pregnant women. Gestational exercise is a potent stimulus for programming vascular smooth muscle relaxation in adult offspring. Specifically, exercise training for the finite duration of pregnancy decreases vascular smooth muscle responsiveness in adult offspring to an exogenous nitric oxide donor.

Assessment of juvenile pigs to serve as human pediatric surrogates for preclinical formulation pharmacokinetic testing.

Pediatric drug development is hampered by biological, clinical, and formulation challenges associated with age-based populations. A primary cause for this lack of development is the inability to accurately predict ontogenic changes that affect pharmacokinetics (PK) in children using traditional preclinical animal models. In response to this issue, our laboratory has conducted a proof-of-concept study to investigate the potential utility of juvenile pigs to serve as surrogates for children during preclinical PK testing of selected rifampin dosage forms. Pigs were surgically modified with jugular vein catheters that were externalized in the dorsal scapular region and connected to an automated blood sampling system (PigTurn-Culex-L). Commercially available rifampin capsules were administered to both 20 and 40 kg pigs to determine relevant PK parameters. Orally disintegrating tablet formulations of rifampin were also developed and administered to 20 kg pigs. Plasma samples were prepared from whole blood by centrifugation and analyzed for rifampin content by liquid chromatography-tandem mass spectrometry. Porcine PK parameters were determined from the resultant plasma-concentration time profiles and contrasted with published rifampin PK data in human adults and children. Results indicated significant similarities in dose-normalized absorption and elimination parameters between pigs and humans. Moreover, ontogenic changes observed in porcine PK parameters were consistent with ontogenic changes reported for human PK. These results demonstrate the potential utility of the juvenile porcine model for predicting human pediatric PK for rifampin. Furthermore, utilization of juvenile pigs during formulation testing may provide an alternative approach to expedite reformulation efforts during pediatric drug development.