Emotions are an integral part of animal welfare.Facial expressions are increasingly used as a non-invasive method for assessing the emotional state of animals.Dogs(Canis familiaris)are closely related to humans,and facial expressions are crucial for interspecies communication and emotional expression.This paper reviews the neurobiological mechanisms of facial expressions and the anatomical structure of the facial muscles and their evolution in dogs,the analogy between dog and human facial expressions,and the expression of various parts of the dog's face under different emotions.These studies demonstrate that dog's facial expressions can be used as a potential indicator of animal welfare,and that dogs can be used as a model animal for studying interspecies facial emotional communication.The use of dog's facial expressions to assess emotions will aid multidisciplinary research,including in the fields of neuroscience,psychopharmacology,animal behavior,and animal welfare.

Emotions are an integral part of animal welfare.Facial expressions are increasingly used as a non-invasive method for assessing the emotional state of animals.Dogs(Canis familiaris)are closely related to humans,and facial expressions are crucial for interspecies communication and emotional expression.This paper reviews the neurobiological mechanisms of facial expressions and the anatomical structure of the facial muscles and their evolution in dogs,the analogy between dog and human facial expressions,and the expression of various parts of the dog's face under different emotions.These studies demonstrate that dog's facial expressions can be used as a potential indicator of animal welfare,and that dogs can be used as a model animal for studying interspecies facial emotional communication.The use of dog's facial expressions to assess emotions will aid multidisciplinary research,including in the fields of neuroscience,psychopharmacology,animal behavior,and animal welfare.

Objective:To investigate the protective effect and mechanism of hydroxysafflor yellow A (HSYA) on severe acute pancreatitis (SAP) related lung injury.Methods:Fifty mice were randomly (random number) divided into five groups: the sham-operated group, SAP group and different doses (20, 40 and 80 mg/kg) of HSYA pretreatment group. Mice were pretreated with HSYA 24 h before SAP induction, pancreatic and lung tissues were isolated for histopathological examination at 72 h after modeling, and bronchoalveolar lavage fluid (BALF) was collected for biochemical analysis. Results:Compared with the sham-operated group, serum amylase activity, lung injury pathological score and BALF protein concentration in the SAP group were significantly increased [(2120.44 ± 354.50) U/L vs. (226.72 ± 20.84) U/L; (6.91 ± 0.28) vs. (0.53±0.18); (2563.25±348.22) μg/mL vs. (345.62±56.35) μg/mL, all P<0.05]. Inflammatory factors tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels and myeloperoxidase (MPO) activity were increased [(120.5±14.25) pg/mL vs. (31.5±4.82) pg/mL; (214.72±10.62) pg/mL vs. (39.26±5.66) pg/mL; (4.52±0.34) U/mg vs. (1.03±0.17) U/mg]. Compared with the SAP group, HSYA pretreatment significantly attenuated SAP-related pancreatic and lung tissue damage and the activities of the inflammatory factors TNF-α, IL-6 and MPO in BALF. In addition, HSYA promoted the expression of the antioxidant protein heme oxygenase-1 and blocked the activation of the NF-κB signaling pathway. Conclusions:HSYA exerts anti-inflammatory and antioxidant activities to inhibit SAP-related lung injury, which indicated that HSYA may be a potential therapeutic drug for SAP-induced lung injury.