Austral Journal of Veterinary Sciences
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A comparison of behavioral and biochemical changes associated with pain between primiparous and multiparous goats around parturition
Get PDFThis study aimed to examine the physiological, biochemical, and behavioral responses of primiparous and multiparous goats during peripartum, as well as their relationship with the discomfort caused by parturition. Eleven primiparous and 10 multiparous dairy goats maintained under intensive conditions were used in this study. Goat behavior was monitored immediately before and during expulsion phase. The behavior of the mother and kid was recorded during the first 2 h postpartum. In the three stages of parturition, the intensity of maternal vocalizations, changes in facial Grimace scale, and blood samples to determine the cortisol, estradiol, and protein concentrations were determined. The weight of the kids and litter size were also considered. Primiparous goats took longer to expel the kid than did multiparous goats (P = 0.04). A negative correlation was found between cortisol concentration and maternal motivation score at 12 and 8 days prepartum (P ? 0.06), as well as at 24 and 48 h postpartum (P ? 0.05). Cortisol concentrations at 4 h postpartum were negatively correlated with the latency of the first lick to the kid (P = 0.01). The latency to suckle was shorter in twin births than in single births kids (P = 0.02). Single birth kids weighed more than twin births kids (P = 0.004). The duration of the first grooming of the kid was shorter in the heavier than in the lighter kids (P = 0.028). The intensity of the vocalizations emitted by the mother in the pre-birth period was greater in the births of heavy offsprings than in those of light offsprings (P = 0.032). The expulsion phase was affected only in primiparous goats. Regardless of parity, cortisol and estradiol concentrations were elevated during parturition; the facial Grimace score and the intensity of vocalizations were greater in the expulsive and postpartum phases
Efficacy of the main anthelmintics used in the control of bovine flukes in warm and humid climate in Mexico
Get PDFFasciola hepatica and paramphistomids are common endoparasites in cattle. Chemical control is the main method to avoid the effects of both trematodes on herd health. This study aimed to evaluate the efficacy of the most commonly used anthelmintics against trematodes (paramphistomids and F. hepatica) in cattle raised in a warm climate in Mexico. Fecal samples were obtained from 393 cows that were naturally infected with F. hepatica and paramphistomids. The fecal egg count was determined using the sedimentation technique, recording the eggs per gram of feces (EPG). Only trematode-positive cows were used to assess anthelmintics such as nitroxynil (NITROX), triclabendazole (TCBZ), fenbendazole (FBZ), rafoxanide (RAFOX), albendazole (ABZ) and oxyclozanide (OCZ). Efficacy was determined following the WAAVP guidelines; samples were taken 15 days post-treatment to perform the fecal egg count reduction test (FECRT). According to FECRT, the efficacy of anthelmintics was 0–83.3% against paramphistomids and 51.8%–100% against F. hepatica. The most effective anthelmintics against F. hepatica were NITROX (89–100%) and RAFOX (93–100%). Triclabendazole in all its combinations (TCBZ + FBZ and ABZ) had lower efficacy in controlling paramphistomids (0–39%), but high efficacy against F. hepatica (59-73%). Most anthelmintics were effective against F. hepatica; however, control alternatives for paramphistomids require further investigation.
Acute Stress Response to Winter Pre-Lambing Shearing in Ewes With and Without Maternal Experience
Get PDFThis study aimed to compare the acute stress response to winter pre-lambing shearing between ewes with and without maternal experience. Twenty-four Finnish Landrace x Polwarth ewes in the last month of gestation were used. Twelve ewes had previous maternal experience (ME), and 12 ewes were undergoing their first pregnancy and were therefore considered without maternal experience (WME). Heart rate, rectal temperature, and eye temperature were recorded immediately before shearing (0 min) and immediately after shearing (5 min). Blood samples were collected, and hormonal (cortisol) and biochemical (total protein, albumin, globulin, and glucose) indicators were determined. Heart rate, rectal temperature, eye temperature, serum cortisol concentration, and plasma glucose level increased after shearing (P < 0.05). Eye temperature significantly increased after shearing only in WME ewes (P = 0.004). The rectal temperature tended to be higher in WME ewes than in ME ewes (P = 0.07). WME ewes had higher serum cortisol concentrations after shearing than ME ewes (P = 0.049). Biochemical indicators did not vary according to the ewes’ maternal experience. In conclusion, ewes’ maternal experience influenced the acute stress response to shearing during late gestation. WME had a greater stress response to shearing than ME, which was evidenced by a higher increases in serum cortisol concentration and eye temperature
Stabilization of Traumatic Thoracolumbar Subluxation using Patient-specific Drill Guide with Double Pin and Polymethylmethacrylate in a 12-year-old Maltese Dog
Get PDFSpinal instability in a 12-year-old Maltese with T11-12 subluxation presenting with neurological symptoms, including hindlimb paraplegia, was treated using double-pin and polymethyl methacrylate (PMMA) fixation. Postoperatively, neurological deficits and hindlimb paraplegia improved, enabling the dog to regain independent ambulation without assistance. Patient-specific drill guides enhanced the accuracy and safety of screw placement, highlighting their potential as an effective method for managing thoracolumbar subluxations in veterinary medicine.
Response of tibia bone morphology, biomechanics and minerals to Organic Hawthorn (Crataegus tanacetifolia) Fruit Vinegar application in broiler chickens exposed to cyclic heat stress
Get PDFThis study aimed to determine the effects of adding different doses of organic hawthorn fruit vinegar (HFV) to the drinking water of male broilers (Ross 308) reared under cyclic heat stress (CHS) on tibia bone morphology, biomechanics, and minerals. Broilers were distributed into six groups based on a 2 × 3 factorial design, testing two ambient temperatures (24 and 35°C CHS for 8 h/day starting from day 21) and three HFV levels (0, 2, and 4 ml/L). Cyclic heat stress had no effect on the morphological and biomechanical properties of the tibia bone, except for a decrease in cortex thickness (P < 0.05). However, CHS significantly decreased the bone Ca, P, Mg, Cu, Zn, Mn, and K levels, while increasing the Fe levels (P < 0.01). The addition of 2 and 4 ml/L HFV had no effect on the morphological and biomechanical properties of the tibia bone (P > 0.05), except for an increase in bone diameter with 2 ml/L HFV (P < 0.05). HFV additions were not sufficient to increase the Ca level decreased by CHS, and the tibia bone Ca level of birds under CHS decreased further with HFV additions (P < 0.01). Conversely, 2 ml/L HFV increased Mg levels, and both 2 and 4 ml/L HFV increased Cu, Fe, Zn, and Mn levels, whereas P levels decreased (P < 0.01). K level decreased with 2 ml/L HFV and increased with 4 ml/L HFV supplementation. In conclusion, HFV supplementation has positive effects on bone mineralization in broilers exposed to HS and can be used up to 4 ml/L to mitigate the negative effects of heat stress
Effects of age, season, breed, and sperm counting chamber on boar semen quality variables in tropical conditions
Get PDFIn the porcine industry, male sperm quality plays a relevant role in the productivity and profitability of the productive system in the tropics. Understanding the factors affecting semen quality is important for optimizing male reproductive efficiency. The present study aimed to evaluate the seminal quality associated with season, breed, age, and sperm counting chamber in boar ejaculates. A total of 22 sexually mature and healthy boars from maternal and sire commercial breeds were utilized as semen donors, with an average age (mean ± standard deviation) of 21.0 ± 7.2 months. The boars were housed individually in well-ventilated pens and fed a standard breeder mix. The boars were grouped according to age into three categories: <12 months, 12-24 months, and >24 months, and semen doses were collected from each boar during the dry and rainy seasons. Ejaculates with at least 75 % morphologically normal sperm and more than 8.5 x 109 total sperm per ejaculate were used. The semen doses were analyzed using Computer-Assisted Semen Analysis (CASA; ISAS® v1). The results showed that younger boars (<12 months) exhibited higher progressive and total sperm motility and faster swimming patterns than older boars. The estimation of total motility and fast spermatozoa increased during the rainy season. The kinematic variables showed significant differences (P < 0.05) between the sperm counting chambers. The Duroc and Landrace breeds presented spermatozoa with greater total motility, whereas the terminal sire line breeds showed accelerated linear progressiveness (P < 0.05). Overall, the impact of various factors on seminal and kinematic variables in boar ejaculates, including age, season, genetic breed composition, and sperm counting chamber, enables us to better understand semen quality in boars. This emphasizes the importance of optimizing swine reproductive management practices in sexually active boars
Epidemiological and clinicopathological characteristics of mammary tumors in female dogs: A retrospective analysis
Get PDFMammary tumors are common neoplasms in female dogs and pose a clinical challenge because of their high malignancy potential. This retrospective study analyzed the medical records of 724 female dogs with 1,638 mammary tumors treated between 2012 and 2022 to assess epidemiological and clinicopathological associations. Malignant tumors (84.6%) were larger than benign ones (3.4 cm vs. 2.3 cm, P<0.01) and were associated with advanced age, multiple tumors, size >5 cm, and ulceration. Tumors >5 cm in size were associated with histological grade III, ulceration, adhesion, and regional metastases. In the multivariate analysis, tumor malignancy was 3.2 times more likely with each additional tumor, 3.3 times more likely with each additional year of age, and 4.8 times more likely with ulcerated tumors. These findings highlight the importance of early diagnosis, comprehensive evaluation, and regular monitoring, especially in high-risk dogs such as elderly and overweight female dogs
Application of a Patient-Specific Saw Guide for Patellar Groove Replacement in a Dog with Medial Patellar Luxation, Osteoarthritis, and Femoral Varus: A Case Report
Get PDFThis case report describes the application of a patient-specific saw guide (PSSG) for patellar groove replacement (PGR) in a dog with severe medial patellar luxation, stifle osteoarthritis, and minor femoral varus deformity. The design, fabrication, and surgical implementation of the PSSG is described, highlighting its feasibility and potential to improve the precision of osteotomy and implant placement in complex orthopedic cases
Research on enteric methane mitigation in Chile: Ten years of scientific insights
Get PDFResearch on enteric methane abatement in Chile began approximately ten years ago and has steadily accelerated. A key challenge in developing strategies to decrease enteric methane emissions in Chile and other countries where ruminant production is largely pasture-based is that globally, most mitigation strategies have been developed and evaluated with confined ruminants fed total mixed rations, requiring adaptation and validation in pasture-based systems. In this review, we discuss in vitro and in vivo applied research of anti-methanogenic strategies conducted in Chile. The reviewed studies included the evaluation of grazing management, different genotypes and species of forages, seasonal forage crops, by-products, oilseeds, and algae supplementation, as well as the use of a chemical inhibitor of methanogenesis, 3-nitrooxypropanol, and the combination of more than one anti-methanogenic strategy. Global meta-analyses and reviews show that intensification of ruminant production consistently decreases methane output per unit of meat or milk and is often economically attractive to producers and acceptable to governments and consumers alike; however, it is generally associated with increased emissions of other greenhouse gases and can result in greater output of carbon dioxide equivalents. Results obtained in Chile with production intensification varied depending on the intensification strategy. We consider that at present, none of the anti-methanogenic strategies investigated thus far in Chile can be recommended for adoption in pasture-based systems. Important aspects to be addressed are the lack of published life cycle assessments, in vivo research in ruminants other than dairy cows, and a considerable proportion of research results available only as conference summaries. Efforts are ongoing to generate solutions to effectively and persistently decrease the emissions of greenhouse gases from Chilean ruminant livestock; however, more research is required to design, adapt, and evaluate enteric methane mitigation strategies applicable to pasture-based systems, which require greater funding from the public and private sectors
Copper toxicosis with hepatic cirrhosis in three dogs: report of a safety alert
Get PDFIn 2020, hundreds of thousands of dogs in Chile were exposed to toxic copper levels in commercial dog food, exceeding the legal copper limit tenfold. We report three fatal hepatic cirrhosis cases after at least three months of consumption of this product. All showed advanced stage liver injury, micro and macroscopic lesions, and high hepatic copper levels.