Serum albumin concentration of donor cows as an indicator of developmental competence of oocytes

Effects of dietary inclusion of 3 Nordic brown macroalgae on enteric methane emission and productivity of dairy cows

Macroalgae are receiving increased attention as antimethanogenic feed additives for cattle, but most in vivo studies are limited to investigating effects of the red macroalgae Asparagopsis spp. Hence, this study aimed to investigate the CH4 mitigating potential of 3 brown macroalgae from the Northern Hemisphere when fed to dairy cows, and to study the effects on feed intake, milk production, feed digestibility, and animal health indicators. The experiment was conducted as a 4 × 4 Latin square design using 4 lactating rumen, duodenal, and ileal cannulated Danish Holstein dairy cows. The cows were fed a total mixed ration (TMR) without any macroalgae or the same TMR diluted with, on a dry matter basis, either 4% ensiled Saccharina latissima, 4% Ascophyllum nodosum (NOD), or 2% Sargassum muticum (MUT). Each period consisted of 14 d of adaptation, 3 d of digesta and blood sampling, and 4 d of gas exchange measurements using respiration chambers. Milk yield and dry matter intake (DMI) were recorded daily. Blood was sampled on d 13 and 16 and analyzed for health status indicators. None of the 3 species affected the CH4 emission. Moreover, milk yield and DMI were also unaffected. Total-tract digestibility of crude protein was significantly lower for NOD compared with other diets, and additionally, the NOD diet also tended to reduce total-tract digestibility of neutral detergent fiber compared with MUT. Blood biomarkers did not indicate negative effects of the dietary inclusion of macroalgae on cow health. In conclusion, none of the 3 brown macroalgae reduced CH4 emission and did not affect DMI and milk production of dairy cows, whereas negative effects on the digestibility of nutrients were observed when A. nodosum was added. None of the diets would be allowed to be fed in commercial dairy herds due to high contents of iodine, cadmium, and arsenic.

Measures of Oxidative Status Markers in Relation to Age, Sex, and Season in Sick and Healthy Captive Asian Elephants in Thailand

Oxidative stress is a pathological condition that can have adverse effects on animal health, although little research has been conducted on wildlife species. In this study, blood was collected from captive Asian elephants for the assessment of five serum oxidative status markers (reactive oxygen species (ROS) concentrations; malondialdehyde, MDA; albumin; glutathione peroxidase, GPx; and catalase) in healthy (n = 137) and sick (n = 20) animals. Health problems consisted of weakness, puncture wounds, gastrointestinal distress, eye and musculoskeletal problems, and elephant endotheliotropic herpesvirus hemorrhagic disease (EEHV-HD). Fecal samples were also collected to assess glucocorticoid metabolites (fGCMs) as a measure of stress. All data were analyzed in relation to age, sex, sampling season, and their interactions using generalized linear models, and a correlation matrix was constructed. ROS and serum albumin concentrations exhibited the highest concentrations in aged elephants (>45 years). No sex differences were found for any biomarker. Interactions were observed for age groups and seasons for ROS and catalase, while GPx displayed a significant interaction between sex and season. In pairwise comparisons, significant increases in ROS and catalase were observed in summer, with higher ROS concentrations observed only in the adult female group. Lower catalase activity was exhibited in juvenile males, subadult males, adult females, and aged females compared to subadult and adult elephants (males and females) in winter and the rainy season. There was a positive association between catalase activity and fGCMs (r = 0.23, p < 0.05), and a number of red blood cell parameters were positively associated with several of these biomarkers, suggesting high oxidative and antioxidative activity covary in red cells (p < 0.05). According to health status, elephants with EEHV-HD showed the most significant changes in oxidative stress markers, with MDA, GPx, and catalase being higher and albumin being lower than in healthy elephants. This study provides an analysis of understudied health biomarkers in Asian elephants, which can be used as additional tools for assessing the health condition of this species and suggests age and season may be important factors in data interpretation.

Species Differences in Tryptophan Metabolism and Disposition

Major species differences in tryptophan (Trp) metabolism and disposition exist with important physiological, functional and toxicity implications. Unlike mammalian and other species in which plasma Trp exists largely bound to albumin, teleosts and other aquatic species possess little or no albumin, such that Trp entry into their tissues is not hampered, neither is that of environmental chemicals and toxins, hence the need for strict measures to safeguard their aquatic environments. In species sensitive to toxicity of excess Trp, hepatic Trp 2,3-dioxygenase (TDO) lacks the free apoenzyme and its glucocorticoid induction mechanism. These species, which are largely herbivorous, however, dispose of Trp more rapidly and their TDO is activated by smaller doses of Trp than Trp-tolerant species. In general, sensitive species may possess a higher indoleamine 2,3-dioxygenase (IDO) activity which equips them to resist immune insults up to a point. Of the enzymes of the kynurenine pathway beyond TDO and IDO, 2-amino-3-carboxymuconic acid-6-semialdehyde decarboxylase (ACMSD) determines the extent of progress of the pathway towards NAD⁺ synthesis and its activity varies across species, with the domestic cat (Felis catus) being the leading species possessing the highest activity, hence its inability to utilise Trp for NAD⁺ synthesis. The paucity of current knowledge of Trp metabolism and disposition in wild carnivores, invertebrates and many other animal species described here underscores the need for further studies of the physiology of these species and its interaction with Trp metabolism.

Colostrogenesis: Role and Mechanism of the Bovine Fc Receptor of the Neonate (FcRn)

Colostrogenesis is a separate and unique phase of mammary epithelial cell activity occurring in the weeks before parturition and rather abruptly ending after birth in the bovine. It has been the focus of research to define what controls this process and how it produces high concentrations of specific biologically active components important for the neonate. In this review we consider colostrum composition and focus upon components that appear in first milked colostrum in concentrations exceeding that in blood serum. The Fc Receptor of the Neonate (FcRn) is recognized as the major immunoglobulin G (IgG) and albumin binding protein that accounts for the proteins' long half-lives. We integrate the action of the pinocytotic (fluid phase) uptake of extracellular components and merge them with FcRn in sorting endosomes. We define and explore the means of binding, sorting, and the transcytotic delivery of IgG1 while recycling IgG2 and albumin. We consider the means of releasing the ligands from the receptor within the endosome and describe a new secretion mechanism of cargo release into colostrum without the appearance of FcRn itself in colostrum. We integrate the insulin-like growth factor family, some of which are highly concentrated bioactive components of colostrum, with the mechanisms related to FcRn endosome action. In addition to secretion, we highlight the recent findings of a role of the FcRn in phagocytosis and antigen presentation and relate its significant and abrupt change in cellular location after parturition to a role in the prevention and resistance to mastitis infections.

Productive performance of beef cows subjected to different nutritional levels in the third trimester of gestation

In general, calf production occurs in less intensive systems. The limitation of nutrients during the gestation phase of beef cows can have negative impacts on the consequent productivity of females. Therefore, this study aimed to evaluate the effects of nutritional levels in the third trimester of pregnancy on the productive performance of beef cows kept in a natural pasture (NP). Eighty-three Charolais × Nelore cows were used, ranging in age from 4 to 12 years, which were divided according to their nutritional levels during the third trimester of pregnancy: NP, cows supplemented with 100% of their energy and protein requirements (SP100) and cows supplemented with 150% of their energy and protein requirements (SP150). The experimental design was completely randomized with three treatments and a varied number of repetitions. The SP100 and SP150 cows presented better body condition at calving (2.92 and 2.99 vs 2.81 points) and at the start of the breeding season (2.90 and 2.95 vs 2.80 points) than did NP cows. The nutritional level of the cows in the third trimester of gestation did not influence the blood metabolite concentrations. The plasma levels of albumin and total proteins were 3.11 and 8.18 g/dl, respectively. Glucose and cholesterol showed values of 74.96 and 166.50 mg/dl. The lowest concentration of blood metabolites was observed in the first postpartum weeks. The SP100 and SP150 cows showed faster follicular growth and, consequently, a higher percentage of females with ovulatory follicles at 21 days postpartum than did NP cows (45.68, 41.11, and 11.00%, respectively). The SP150 cows had a higher pregnancy rate (40.74%), total calf production (295.88 kg/cow), and consequently, offspring sale value. An increased nutritional level in the third trimester of pregnancy improves the postpartum metabolic condition and productive efficiency of beef cows kept on NP.

Nutrient requirements in Hanwoo cows with artificial insemination: effects on blood metabolites and embryo recovery rate

Here, we investigated the effects of different nutrient requirements (NR) on blood metabolites, transferable embryo number after multiple superovulations with artificial insemination (AI), body condition score (BCS), and estrus cycle in Hanwoo cow. Nineteen Hanwoo cows were randomly divided into three groups (80%, 100%, and 120% NR, containing 6, 8, and 5 individuals, respectively) and fed based on the NR. In experiment 1, glucose, total cholesterol, triglyceride, blood urea nitrogen (BUN), aspartate aminotransferase (AST), alanine aminotransferase (ALT), non-esterified fatty acids (NEFA), albumin (ALB), and total protein (TP) were analyzed. In experiment 2, total number of recovered embryos and transferable embryos was examined after embryo recovery and multiple superovulations with AI. In experiment 3, body weight, BCS, and estrus cycle were examined. In experiment 1, total cholesterol was significantly different among the 80%, 100%, and 120% NR groups (126.5 ± 3.3, 152.6 ± 2.4, and 177.4 ± 1.8 mg/dL, respectively, p < 0.05). The triglyceride and BUN levels in the 120% NR group were significantly higher than those in the 80% and 100% groups (p < 0.05). The NEFA levels were significantly different among the 80%, 100%, and 120% NR groups (440.5 ± 18.2, 318.5 ± 23.1, and 195.1 ± 8.5 ЧEq/L, respectively, p < 0.05). The AST and TP levels in the 80% NR group were significantly lower than those in the 100% and 120% NR groups (p < 0.05). In experiment 2, the 120% NR group showed a higher percentage of transferable embryos than the 80% and 100% groups (p < 0.01). The mean body weight and BCS among the 80%, 100%, and 120% NR groups were significantly different (p < 0.05). The estrus cycle in the 80% NR group was delayed compared with the 100% and 120% NR groups (20.8 ± 0.2 and 21.2 ± 0.5 days, respectively). In conclusion, the blood metabolic tests proved that Hanwoo cows with 120% NR can produce a large number of transferable embryos. Thus, 120% NR is the appropriate feeding level for this type of cows as it results in the production of a large number of transferable embryos by multiple superovulations with AI.

Associations of plasma total phospholipid fatty acid patterns with feeding practices, growth, and psychomotor development in 6-month-old South African infants

The objective of this study was to assess plasma fatty acid (FA) patterns of 6-month-old South African infants and to determine their association with feeding practices, growth, and psychomotor development. Plasma total phospholipid FA composition (% of total FAs) of 6-month-old infants (n = 353) from a peri-urban township was analysed, and principal component and factor analysis were performed to identify plasma FA patterns. Feeding practices, anthropometric measurements, and psychomotor development scores were determined. Four major plasma phospholipid FA patterns were identified: A plant-based C18 FA, a high n-6 long-chain polyunsaturated fatty acids (LCPUFA), a C16:1 and long-chain saturated fatty acid (SFA), and a high n-3 and low n-6 LCPUFA pattern. Formula feeding was associated with higher, whereas breastfeeding was associated with lower scores for the plant-based C18 FA and C16:1 and long-chain SFA patterns. On the other hand, breastfeeding, the consumption of cow's milk, and the consumption of semisolid foods were associated with higher scores, whereas formula feeding was associated with lower scores for the high n-6 LCPUFA pattern. Breastfeeding and the consumption of semisolids were also associated with higher high n-3 and low n-6 LCPUFA pattern scores. The C16:1 and long-chain SFA and high n-3 and low n-6 LCPUFA patterns were positively associated with psychomotor development scores. In 6-month-old South African infants, we identified distinct plasma FA patterns that presumably represent the FA quality of their diet and that are associated with psychomotor development. Our results suggest that breast milk is an important source of n-6 LCPUFAs and formula-fed infants may be at risk of inadequate LCPUFA intake.

Embryo production in middle-aged and mature Bos taurus × Bos indicus cows induced to multiple ovulation in a tropical environment

The objective of the study was to evaluate embryo production in middle-aged and mature Bos taurus × Bos indicus cows induced to multiple ovulation (MO) in a tropical environment. Twenty-eight cows were assigned into two groups: (1) middle-aged cows = 4-6 years old (n = 13), and (2) mature cows = 8-12 years old (n = 15). All donors received the same MO protocol with follicle-stimulating hormone in decreasing dose during 4 days and two artificial insemination services. Total numbers of corpora lutea at embryo collection, structures collected, and viable embryos obtained, as well as recovery rate, were higher in middle-aged cows compared with mature cows (P < 0.05). A total number of degenerate embryos and unfertilized oocytes, as well as viability rate, were similar in both groups (P > 0.05). In conclusion, the mature cows responded to the MO treatment, but the average of viable embryos recovered per donor was lower than in middle-aged cows. Therefore, the inclusion of cows ≥ 8 years old as donors in MO programs in tropical environments should be avoided.