Revista Colombiana de Ciencias Pecuarias

Genotypic and allelic variability of calpain CAPN1-316 gene in Tropical Milking Criollo cattle

Anayeli Torres-Beltrán — 2024-07-16

Background: Genes and their variants associated with milk and beef production traits in cattle can be identified through molecular markers. Calpain gene CAPN1-316 has been associated with meat tenderness in several breeds. Tropical Milking Criollo males not selected as breeders are usually destined to commercial beef production. Objective: To estimate genotypic and allelic frequencies of calpain CAPN1-316 gene -associated with meat tenderness- in Tropical Milking Criollo cattle breed. Methods: Molecular marker microsatellites of single sequence repeats (SSR) from DNA were extracted from blood samples of 423 purebred animals from three farms to identify variants of CAPN1-316 using polymerase chain reaction (PCR). Genotypic and allelic frequencies within populations, genetic distance, heterozygosity, and Xi squared (X2) test were performed using POPGENE software. Results: Genotypic frequencies of the whole population were CC 0.31, GG 0.18, and CG 0.51. Allelic frequencies of variant C per farm were 0.62, 0.60, and 0.52. Genotypic and allelic frequencies of the CAPN1-316 polymorphisms were in Hardy-Weinberg equilibrium (X2, p>0.05). The CC genotype showed indication of greater meat tenderness. Conclusion: The C variant of CAPN1-316 gene -favorable to meat tenderness- has higher frequency than the G variant in Tropical Milking Criollo cattle.

Effect of breed, parity number, and location on productive and reproductive parameters of dairy cattle

Cristian-Camilo Rúa-Giraldo — 2024-06-19

Background: Productive and reproductive parameters of dairy cattle in the high tropics are affected by various factors related to management, but also by specific factors such as breed, calving, and herd location. Objective: To analyze the effects of breed, calving, and location on herd efficiency by assessing productive and reproductive information from dairy herds in Antioquia province (Colombia). Methods: Productive and reproductive information from 5,440 records of cows between 1 and 11 calvings and various breeds and crosses was obtained. The animals belonged to 57 herds from 16 municipalities in three dairy regions of Antioquia province: North-N, East-E, and Valle de Aburrá-V. The variables analyzed were milk production adjusted to 305 days (PLa), kilograms of protein per lactation (KgPRO), kilograms of fat per lactation (KgF), somatic cell score (SCS), number of services per conception (S/C), days open (DO), and calving interval (CI). The independent variables were associated with the parameters through a generalized linear model (GLM). Results: The total PLa average was 5,492.6 (±1,027.2) kg/lactation. The values were 177.1 (±29.5) and 215.1 (±37.1) kg/lactation for KgPROa and KgFa, respectively. For SCS, an average value of 3.62 (±1.6) was found. Reproductive parameters were 2.02 (±1.4), 385.7 (±52.8) days, and 110.9 (±55.4) days for S/C, CI, and DO, respectively. Ayrshire × Holstein cows from region V, presented low PLa (58%). Holstein cows in their third parturition presented low PLa (31%), somewhat similar to the decrease in PLa of Ayrshire in second calving (56%). Furthermore, decreased milk production was observed in Angus × Holstein cows (46% less PLa) and in Brown Swiss in region V, with 41% less milk per lactation. The KgFa data decreased when compared to the general average, with values of 172.9±24.7 kg for Holstein, 132.5±46.2 kg for Ayrshire × Holstein in E region, and 102.2±26.5 kg in Ayrshire × Jersey cows. The longest CI was significantly (p<0.05) associated with the third parity and with the Holstein breed (37% increase) and with BON × Holstein crosses (57% increase). Conclusions: Productive and reproductive parameters are variable, and multiple interacting independent variables –such as breed, parity and location- lead to decrease or increase in the studied parameters.

Effect of iron injection strategies for suckling piglets on pre- and post-weaning growth performance and hematocrit levels

Gabriella Lima — 2024-08-01

Background: A single, 200-mg iron injection for newborn pigs is a common practice in swine production. It is required to provide sufficient iron for newborn pigs while avoiding the potential risk of excessive amount of iron causing oxidative stress. Objective: To evaluate the quantity and timing of a single or second iron injection into suckling piglets on growth performance and hematocrit levels. Methods: A total of 24 piglets from four litters were used in each experiment (3). Treatments were: Experiment 1- 1) Control: 150 mg iron injection at d 1-3 of age, 2) Iron14: additional 100 mg iron injection at 14 d before weaning, and 3) Iron7: additional 100 mg iron injection at 7 d before weaning; Experiment 2- 1) Control: 100 mg iron injection at d 1-3 of age, 2) Iron100/100: 100 mg iron at d 1-3 of age and 9 d after the first injection, and 3) Iron200: 200 mg iron injection at d 1-3 of age; and Experiment 3 (at d 3-4 of age)- 1) Fe100: 100 mg iron injection, 2) Fe200: 200 mg iron injection, and 3) BW200: 125 mg iron injection/kg body weight. Pigs were weaned at d 25-28 of age. Growth performance and hematocrit levels were measured until d 13-14 postweaning. Results: In Experiment 1, the Iron14 treatment had a greater final body weight than the control treatment (p=0.07). Hematocrit levels were greater in the Iron14 (p=0.10) and Iron7 (p<0.05) treatments than in the control treatment at d 14 postweaning. In Experiment 2, average daily gain in the postweaning period was greater in the Iron100/100 treatment than in the control (p<0.05) and Iron200 (p=0.08) treatments. Hematocrit levels in the Iron200 treatment were greater than those in the control treatment (p<0.05) at d 13 postweaning. In Experiment 3, there was no difference in growth performance, but the BW200 treatment increased hematocrit levels to a greater degree than the Fe200 treatment (p<0.10). Conclusion: An additional iron injection earlier and a split iron injection to newborn pigs could benefit postweaning growth, but not by body weight-based iron injection. Hematocrit levels increase with a greater dose of iron injected although the magnitude varies depending on injection strategies.

Effect of acetaminophen on hepatic enzymes and renal analytes of ovary-hysterectomized dogs

Angelica Olivares-Muñoz — 2024-07-16

Background: Pain treatment in companion animals is of great importance nowadays. Alternative pain therapies should be studied in small species to improve life quality and well-being of patients. For years, acetaminophen has been misused in dogs and cats, producing toxic effects after administration at high doses. Objective: To evaluate the effects of pre- and post-surgical administration of acetaminophen (also called paracetamol) on renal and hepatic enzymes in dogs undergoing ovarian hysterectomy surgery, and its effect as a trans- and post-surgical analgesic therapy. Methods: An acetaminophen dose was administered 30 minutes before surgery and 48 hours after the procedure. Pain was assessed with the Glasgow Pain Scale during surgery and at 2, 6, 12 and 24 hours after the surgical procedure. Blood studies were performed seven days before surgery and five days after to evaluate the effect of acetaminophen on liver enzymes and renal analytes. Results: No significant changes in renal analytes and liver enzymes were observed after drug application every 6 and 8 hours for 48 hours. Furthermore, anesthesia and analgesia remained stable during the surgical procedure and a low score on pain scale was observed, indicating absence of postoperative pain despite the total time of surgery was longer than usual. Conclusion: Acetaminophen is an excellent analgesic for prolonged surgery and also for postoperative pain. Furthermore, it does not produce hepatic or renal alterations at the tested doses.

Barriers and strategies for scaling up livestock agroforestry systems in the Colombian amazon piedmont

Antonio Solarte — 2024-06-24

Background: Silvopastoral systems (SPS) are sustainable livestock production systems with multiple benefits. Nevertheless, its adoption has been limited. Objective: To identify the barriers encountered by farmers to adopt SPS, considering the perceptions of producers and the strategies to promote its adoption as a tool for sustainable cattle ranching in the Amazonian foothills of Caquetá province, Colombia. Methods: Experts on sustainable cattle ranching from public and private organizations implementing projects in Caquetá were called to contribute to participatory rural appraisal workshops and focus groups. In these workshops also participated producers from the south of the province with three to five years of experience in establishment SPS, and producers from north of the province who were just starting with SPS. Results: The experts recognized 13 practices promoted by institutions for sustainable cattle ranching. These alternatives were categorized into pasture management, livestock agroforestry, conservation, and renewable energy systems. They also identified 21 barriers that limit the adoption of these alternatives, which were grouped into skills and knowledge, social, economic, environmental, and technical and operational barriers. The cattle farmers prioritized and established the advantages and disadvantages of the four main SPS. In response to the barriers, 22 scaling-up strategies were identified and classified into five categories contributing to promote the adoption of SPS. Conclusions: Organizations promoting sustainable practices for cattle ranching and farmers in the Caquetá foothills recognize the importance of SPS, but there are still barriers related to knowledge, implementation costs, environmental, and cultural conditions that need to be addressed to increase its adoption.