Tratamiento de la alergia a la proteína de la leche de vaca. Consenso interdisciplinario de expertos / Cow's milk allergy treatment. An expert consensus

El tratamiento de la alergia a las proteínas de la leche de vaca se basa en la eliminación completa de las proteínas de leche de vaca de la dieta del niño y de la madre en los que reciben leche materna. Para lograr la remisión de los síntomas y la tolerancia futura, la exclusión debe ser total. En los niños que reciben fórmula, esta deberá tener hidrolizado extenso de proteínas en las formas leves o moderadas, mientras que aquellas a base de aminoácidos se reservan para los casos más graves. El tiempo de tratamiento, la adquisición de tolerancia y el momento para la prueba de provocación oral van a variar según el cuadro clínico, el mecanismo inmunológico implicado y la edad del paciente. El objetivo de este consenso ha sido reflejar el conocimiento actualizado junto con la experiencia de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología.

The treatment of cow's milk protein allergy is based on the complete elimination of cow's milk protein from the diet. To achieve remission of symptoms and future tolerance, exclusion must be total. In formula fed infants the extensively hydrolysed formula is the most appropriate option in mild or moderate forms, while those based on amino acids are reserved for the most severe cases. The treatment time, the acquisition of tolerance and the moment for the oral provocation test will vary according to the clinical picture, the immunological mechanism involved and the age of the patient. The aim of this consensus has been to reflect the updated knowledge together with the experience of neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology

Association between non-esterified fatty acids and calcium concentrations at calving with early lactation clinical diseases, fertility and culling in grazing dairy cows in Uruguay.

This study describes the association of non-esterified fatty acids (NEFA) and calcium concentrations at calving with early lactation disease, reproductive performance and culling in 646 dairy cows from 13 commercial grazing dairy herds in Uruguay. During one year, health events were recorded from calving to 30 days in milk (DIM). The first author visited each farm every 20 days. During each visit, body condition score (BCS) was recorded (scale 1-5), defining BCS < 3 as suboptimal and BCS > 3 as optimal, and a blood sample was taken from cows between 0 and 4 DIM for metabolite determination. To evaluate the association between health events (i.e., retained placenta-metritis and clinical mastitis) and risk factors (parity, BCS, high NEFA (> 0.6 mmol/L) and subclinical hypocalcemia (SCH) (< 2.10 mM)) data were analysed using multivariable logistic regression models. To evaluate the association of health events and risk factors with reproductive performance and culling, data were analysed using Cox proportional hazard regression models. A risk factor and an outcome of interest were assumed to be associated at P < 0.05 and a tendency to be associated was defined at P < 0.10. Overall, 47 % (n = 303) of the cows showed elevated NEFA concentration and 77 % (n = 499) had SCH. In addition, 21.5 % (n = 139) of the cows recorded at least one clinical disease. Cumulative incidence was 17 % (n = 109) for clinical mastitis, 4.2 % (n = 27) for retained placenta (RP)-metritis and 1.4 % (n = 7) for lameness. Clinical mastitis was associated with parity, with lower odds in primiparous (PP) cows (OR = 0.42, P < 0.01). Cows in an optimal BCS also tended to have lower odds (OR = 0.66, P = 0.07). Moreover, high NEFA and SCH cows had higher odds of CM (OR = 4.5, P = 0.01 and OR = 1.75, P = 0.04, respectively). Retained placenta-metritis tended to be associated with high NEFA concentration (OR = 2.2, P = 0.06). Primiparous cows with suboptimal BCS showed an increased first insemination rate (HR = 2.34; P < 0.01). The risk of culling was lower in PP cows (HR = 0.19; P < 0.01) and in cows with optimal BCS and low NEFA concentration (HR = 0.38; P = 0.03). Our data show that metabolic challenge (defined as peripartum suboptimal BCS, high NEFA or SCH) is associated with increased odds of clinical mastitis and RP-metritis, decreased probability of insemination and increased hazard of culling. Under grazing conditions, we suggest that farm management to improve the metabolic adaptation to lactation represents an opportunity to enhance cow performance in terms of health, fertility and longevity.

A hurdle strategy based on the combination of non-thermal treatments to control diarrheagenic E. coli in cheese.

This study aimed to assess the efficacy of a multi-hurdle process combining mild High Hydrostatic Pressure (HHP) treatments and Thyme Oil (TO) edible films as a non-thermal method to combat pathogenic E. coli (aEPEC and STEC) in raw cow's-milk cheese stored at 7 °C and packaged under modified atmosphere. Changes in headspace atmosphere of cheese packs and treatment effects on Lactic Acid Bacteria (LAB) counts and diarrheagenic E. coli strains (aEPEC and STEC) were evaluated over a 28 d storage period. The results demonstrated that the combined treatment exhibited the most significant antimicrobial effect against both strains compared to individual treatments, achieving reductions of 4.30 and 4.80 log cfu/g after 28 d of storage for aEPEC and STEC, respectively. Notably, the synergistic effect of the combination treatment resulted in the complete inactivation of intact cells for STEC and nearly completed inactivation for aEPEC by the end of the storage period. These findings suggest that the combination of HHP with selected hurdles could effectively enhance microbial inactivation capacity, offering promising alternatives for improving cheese safety without affecting the starter microbiota.

State of the art of the cow-calf systems in beef and dairy cattle (Bos taurus) operations in EU, USA, and Brazil from 1998 to 2023.

Cow-calf systems represent a significant research area in animal husbandry, with differences depending on the final product (meat or milk). This study aimed to apply text mining and topic analysis on literature describing cow-calf systems in European, American, and Brazilian beef and dairy sectors between 1998 and 2023. Additionally, cow-calf contact (CCC) literature data was manually extracted. Our findings revealed the presence of 11 research areas among literature on cow-calf systems, with different priorities identified in the beef and dairy sectors. Beef industry mainly focused on animal proficiency and nutrition, while dairy on animal welfare and CCC, which showed a growing trend as emerging research topic, mostly in the EU. Current debates around calf welfare and EU's planned animal welfare legislation revision appeared to be driving the increasing interest in this topic. Studies in the beef sector were mainly localized in Brazil, showing that research in different contexts and species is important for CCC implementation. Manual data extraction showed considerable variation in the retained CCC documents regarding sample size, type of contact, methods and CCC duration. Learning about the varied CCC approaches used in beef and dairy farms in different locations, concentrating on their strengths and weaknesses, will help to develop novel solutions to global challenges. Adopting validated and robust indicators would help scientists and policymakers to monitor the system's quality. To improve CCC feasibility, match consumer demands, and move towards One Welfare and One Health, future research should focus on a variety of situations to overcome the current shortcomings.

Alergia a las proteínas de la leche de vaca: proceso diagnóstico. Consenso interdisciplinario de expertos / Cow's milk allergy: diagnostic process. Expert consensus

Las proteínas de la leche de vaca pueden causar alergia alimentaria. Los distintos mecanismos de acción involucrados y la variabilidad clínica según la etapa de la vida pediátrica en la que se manifieste ocasionan dificultades en su abordaje, con riesgo de sub- o sobrediagnóstico. En este proceso, intervienen profesionales de diversas áreas y es recomendable su interacción. Es por ello que el objetivo de este consenso ha sido reflejar el conocimiento actualizado desde la interdisciplina, generando recomendaciones para su correcto diagnóstico. Hemos trabajado con el método de Delphi para sumarle a la evidencia científica, la experiencia proveniente de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología. Pensamos que este enfoque interdisciplinario de trabajo va a resultar de utilidad práctica y promoverá una atención más integral de estos pacientes.

Cow's milk protein can cause food allergy. The different mechanisms of action involved, the clinical variability depending on the stage of pediatric life in which it manifests, leads to difficulties in its approach, with the risk of under- or over-diagnosis. Professionals from various areas intervene in this process and their interaction is recommended. That is why the objective of this consensus has been to reflect the updated knowledge in an interdisciplinary mode, generating recommendations for its correct diagnosis. We have worked with the Delphi method to add to the scientific evidence, the experience from neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology. We think that this interdisciplinary approach will be of practical use and will promote more comprehensive care for these patients.

Assessment of Ammonia Emissions and Greenhouse Gases in Dairy Cattle Facilities: A Bibliometric Analysis.

A deeper understanding of gas emissions in milk production is crucial for promoting productive efficiency, sustainable resource use, and animal welfare. This paper aims to analyze ammonia and greenhouse gas emissions in dairy farming using bibliometric methods. A total of 187 English-language articles with experimental data from the Scopus and Web of Science databases (January 1987 to April 2024) were reviewed. Publications notably increased from 1997, with the highest number of papers published in 2022. Research mainly focuses on ammonia and methane emissions, including quantification, volatilization, and mitigation strategies. Other gases like carbon dioxide, nitrous oxide, and hydrogen sulfide were also studied. Key institutions include the University of California-Davis and Aarhus University. Bibliometric analysis revealed research evolution, identifying trends, gaps, and future research opportunities. This bibliometric analysis offers insights into emissions, air quality, sustainability, and animal welfare in dairy farming, highlighting areas for innovative mitigation strategies to enhance production sustainability. This research contributes to academia, enhancing agricultural practices, and informing environmental policies. It is possible to conclude that this research is a valuable tool for understanding the evolution of research on gas emissions in dairy cattle facilities, providing guidance for future studies and interventions to promote more sustainable production.

Low-performance diagnosis of covered anaerobic lagoons as a waste management strategy in the intensive dairy industry.

Covered anaerobic lagoons (CALs) are Latin America's main livestock waste treatment systems. Mexico has 680 CALs that present low biogas yields (0.05 m3 m-3 digester d-1) and low COD removal rates (< 60%). This work focused on diagnosing CAL´s low performance in dairy farms by determining and analyzing operational parameters. Seven CALs located in the main dairy basin of Mexico were analyzed. The sampling areas for each CAL were the supernatant, the active zone, settled sludge, and digester inlet and outlet. The variation of the process parameter values corroborated that CALs appeared stratified and not working as expected. The sludge zone, comprising 50-58% of total solids content and 1-15% of total CALs volume, showed an elemental compounds content suitable for organic fertilizer (340, 48, and 5 kg t-1 of C, N, and S, respectively). However, this zone contained, at least, 85% of the slowly hydrolysable material; the methanogenic potential was less than 87 mL CH4 g VS-1, and the C/N ratio ranged from 4.9 to 17, outside of the optimal range. The biogas produced did not exceed 60% of methane content and more than 3000 ppm of H2S. The sludge zone significantly influences the lagoon's dynamics since it is a nutrient sink. Furthermore, the lack of agitation is the leading cause for the low energy yield and the low removal of organic matter rate. This work provides valuable information to address the operational problems within the CALs improving our understanding that shall allow proposing reactivation alternatives.

[Cow's milk allergy: diagnostic process. Expert consensus]. / Alergia a las proteínas de la leche de vaca: proceso diagnóstico. Consenso interdisciplinario de expertos.

Cow's milk protein can cause food allergy. The different mechanisms of action involved, the clinical variability depending on the stage of pediatric life in which it manifests, leads to difficulties in its approach, with the risk of under- or over-diagnosis. Professionals from various areas intervene in this process and their interaction is recommended. That is why the objective of this consensus has been to reflect the updated knowledge in an interdisciplinary mode, generating recommendations for its correct diagnosis. We have worked with the Delphi method to add to the scientific evidence, the experience from neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology. We think that this interdisciplinary approach will be of practical use and will promote more comprehensive care for these patients.

Las proteínas de la leche de vaca pueden causar alergia alimentaria. Los distintos mecanismos de acción involucrados y la variabilidad clínica según la etapa de la vida pediátrica en la que se manifieste ocasionan dificultades en su abordaje, con riesgo de sub- o sobrediagnóstico. En este proceso, intervienen profesionales de diversas áreas y es recomendable su interacción. Es por ello que el objetivo de este consenso ha sido reflejar el conocimiento actualizado desde la interdisciplina, generando recomendaciones para su correcto diagnóstico. Hemos trabajado con el método de Delphi para sumarle a la evidencia científica, la experiencia proveniente de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología. Pensamos que este enfoque interdisciplinario de trabajo va a resultar de utilidad práctica y promoverá una atención más integral de estos pacientes.

[Cow's milk allergy treatment. An expert consensus]. / Tratamiento de la alergia a la proteína de la leche de vaca. Consenso interdisciplinario de expertos.

The treatment of cow's milk protein allergy is based on the complete elimination of cow's milk protein from the diet. To achieve remission of symptoms and future tolerance, exclusion must be total. In formula fed infants the extensively hydrolysed formula is the most appropriate option in mild or moderate forms, while those based on amino acids are reserved for the most severe cases. The treatment time, the acquisition of tolerance and the moment for the oral provocation test will vary according to the clinical picture, the immunological mechanism involved and the age of the patient. The aim of this consensus has been to reflect the updated knowledge together with the experience of neonatologists, pediatricians, experts in allergy, nutrition and gastroenterology.

El tratamiento de la alergia a las proteínas de la leche de vaca se basa en la eliminación completa de las proteínas de leche de vaca de la dieta del niño y de la madre en los que reciben leche materna. Para lograr la remisión de los síntomas y la tolerancia futura, la exclusión debe ser total. En los niños que reciben fórmula, esta deberá tener hidrolizado extenso de proteínas en las formas leves o moderadas, mientras que aquellas a base de aminoácidos se reservan para los casos más graves. El tiempo de tratamiento, la adquisición de tolerancia y el momento para la prueba de provocación oral van a variar según el cuadro clínico, el mecanismo inmunológico implicado y la edad del paciente. El objetivo de este consenso ha sido reflejar el conocimiento actualizado junto con la experiencia de neonatólogos, pediatras, especialistas en alergia, nutrición y gastroenterología.

A real-world cross-sectional study evaluating the role of an oral amino acid-based supplement in nutrient intake by preschoolers on a cow's milk elimination diet.

INTRODUCTION AND OBJECTIVES: Food allergy has several negative nutritional consequences and may persist beyond the first year of lives. This study aimed to assess the role of a complete oral amino acid-based supplement in the diet of children on cow's milk protein elimination diet because of food allergy. MATERIALS AND METHODS: This study included two groups of children aged 1-5 years paired by age and socioeconomic status: (1) study group, on cow's milk protein elimination diet plus an oral amino acid-based supplement, and (2) control group, on cow's milk protein elimination diet. Sociodemographic, clinical, anthropometric, and dietary data were obtained through online interviews. Two 24-h dietary recalls were collected on nonconsecutive days. Both groups comprised mostly boys. RESULTS: The study group presented lower values of body mass index. The frequency of feeding difficulties was similar between groups. The study group had a higher intake of energy, protein, carbohydrates, calcium, iron, zinc, phosphorus, magnesium, copper, selenium, vitamins D, E, B1, B2, B6, and B12, niacin, and folic acid compared to the control group. A higher proportion of children in the study group had adequate intake according to the recommendations made for energy, carbohydrates, iron, phosphorus, selenium, vitamins A, D, E, B1, B2, and B6, and folic acid. CONCLUSIONS: The use of a complete oral amino acid-based supplement has a positive effect on the diet quality of preschoolers on cow's milk elimination diet because of food allergy, promoting higher intake of energy, calcium, vitamin D, and other essential nutrients.

Is prolonged luteal phase a problem in lactating Holstein cows?

In this study, the main objective was to assess if long luteal phases could have causes other than pregnancy loss. We enrolled Holstein dairy cows ≥50 DIM from a commercial herd in Brazil from October 2016 to August 2017. All cows received an estradiol-based synchronization protocol, and, on the day of insemination (d 0), were randomly assigned either an AI or a placebo insemination (PBO) in a 3:1 ratio. An ultrasound was used to assess the presence of a corpus luteum (CL) on d 17, 24, and 31, which, combined to the information from patches for the detection of estrus, was used to determine the length of the luteal phase following AI or PBO. Pregnancy was assessed by ultrasound on d 31 and cows that were pregnant were excluded from the analyses. The length of the estrous cycles was categorized as short (<17 d), normal (17-23 d), long (24-30 d), and very long (≥31 d). We compared the proportion of cows in each category between the AI and PBO groups using a cumulative ordinal mixed model. We define prolonged luteal phase as estrous cycles ≥24 d and tested its association with potential risk factors (parity, season, DIM, uterine size and position score, milk production, BCS, and the presence of a CL at enrollment to the synchronization protocol) using mixed logistic regression models. Results are presented as odds ratio (OR) and 95% Bayesian credible intervals (BCI). Data from 876 inseminations (AI: n = 616, PBO: n = 260) was collected. Overall, 12% of estrous cycles were short, 31% were normal, 19% were long, and 38% were very long. There was no difference in the odds of being in longer estrous cycle categories for the AI compared with the PBO group (OR = 0.92; 95% BCI = 0.76-1.10). Season and presence of a CL at enrollment were associated with prolonged luteal phase. In the AI group, there was a possible effect of early pregnancy losses on the lifespan of the CL, but not the PBO group, which led us to conclude that long and very long estrous cycles were not all caused by the embryonic loss. In fact, the high prevalence of cows with an extended CL lifespan in the present study suggests this could be an under- or miss-reported characteristic of high-producing lactating Holstein cows. This finding may have important repercussions in the understanding of the CL function physiology of lactating Holstein cows.

α-Pinene Improves Follicle Morphology and Increases the Expression of mRNA for Nuclear Factor Erythroid 2-Related Factor 2 and Peroxiredoxin 6 in Bovine Ovarian Tissues Cultured In Vitro.

Oxidative stress during in vitro of ovarian tissues has adverse effects on follicle survival. α-pinene is a monoterpenoid molecule with antioxidant activity that has great potential to maintain cell survival in vitro. This study investigated the effect of α-pinene (1.25, 2.5, 5.0, 10.0, or 20.0 µg/mL) on primordial follicle growth and morphology, as well as on stromal cells and collagen fibers in bovine ovarian slices cultured for six days. The effect of α-pinene on transcripts of catalase (CAT), superoxide dismutase (SOD), peroxiredoxin 6 (PRDX6), glutathione peroxidase (GPX1), and nuclear factor erythroid 2-related factor 2 (NRF2) was investigated by real-time PCR. The tissues were processed for histological analysis to evaluate follicular growth, morphology, stromal cell density, and collagen fibers. The results showed that 2.5, 5.0, or 10.0 µg/mL α-pinene increased the percentages of normal follicles but did not influence follicular growth. The α-pinene (10.0 µg/mL) kept the stromal cell density and collagen levels in cultured bovine ovarian tissue like uncultured tissues. Ovarian tissues cultured in control medium had reduced expression of mRNA for NRF2, SOD, CAT, GPX1, and PRDX6, but α-pinene (10.0 µg/mL) increased mRNA levels for NRF2 and PRDX6. In conclusion, 10.0 µg/mL α-pinene improves the follicular survival, preserves stromal cell density and collagen levels, and increases transcripts of NRF2 and PRDX6 after in vitro culture of bovine ovarian tissue.

Nanoparticles Partially Restore Bacterial Susceptibility to Antibiotics.

The growing resistance of bacteria to antibiotics is one of the main public health problems nowadays. The influence of silver nanoparticle (AgNP) pretreatment of 220 cows with mastitis on the susceptibility of Staphylococcus epidermidis bacteria to 31 antibiotics was studied. The obtained results were compared with the previous results for Escherichia coli, Streptococcus dysgalactiae, and Staphylococcus aureus. For all four bacteria, an increase in susceptibility (9.5-21.2%) to 31 antibiotics after cow treatment with AgNPs was revealed, while after first-line antibiotic drug treatment as expected, the susceptibility decreased (11.3-27.3%). These effects were explained by (1) the increase in the contribution of isolates with efflux effect after antibiotic treatments and its decrease after AgNP treatment and (2) the changes in bacteria adhesion and anti-lysozyme activity after these treatments. The effect of the increasing antibacterial activity of antibiotics after AgNP treatment was the most pronounced in the case of E. coli and was minimal in the case of S. epidermidis. With AgNP treatment, the time of recovery decreased by 26.8-48.4% compared to the time of recovery after treatment with the first-line antibiotic drugs. The AgNP treatment allows for achieving the partial restoration of the activity of antibiotics.

Antibiotic residues and microbial contamination in pasteurized whole milk intended for human consumption.

Background and Aim: Milk contamination for human consumption is one of the biggest concerns worldwide. To prevent milk contamination, it is important to implement sustainable production practices that ensure animal health and guarantee veterinary drugs have been used properly. This study aimed to detect antibiotic residues and microbial contamination in commercially available pasteurized whole milk intended for human consumption. Materials and Methods: We conducted a cross-sectional study on all brands of pasteurized milk (n = 17) for human consumption in Medellín, Colombia, from February 30 to April 30, 2022. Six milk samples of each brand were collected every 15 days, resulting in 102 samples. IDEXX SNAPduo™ ST Plus test (IDEXX Laboratories Inc, Maine, USA) was used to detect cephalosporins residues to detect beta-lactam and tetracyclines. We detected mesophilic aerobic bacteria and coliforms using Chromocult Coliform Agar® (Merck KGaA, Darmstadt, Germany) and Plate-Count Agar® (Merck KGaA), respectively. Results: Beta-lactam residues were found in 24.4% of the brands. No tetracyclines or cephalosporins were detected. Mesophilic aerobic bacteria and coliform contamination were detected in 42.6% and 12.8% of the brands, respectively. No fecal coliform contamination was detected. Conclusion: This study demonstrated the presence of antibiotic residues and microbial contamination in commercially available pasteurized whole milk intended for human consumption in the study area, highlighting its potential public health implications.

Periparturient blood T-lymphocyte PD-1 and CTLA-4 expression as potential predictors of new intramammary infections in dairy cows during early lactation (short communication).

BACKGROUND: The periparturient period in dairy cows is marked by immunosuppression which increases the likelihood of infectious disorders, particularly also mastitis. An in-depth understanding of peripartum leukocyte biology is vital for the implementation of highly successful post-partum disease prevention measures. Immune checkpoint molecules, such as programmed death 1 (PD-1) and cytotoxic T-lymphocyte antigen 4 (CTLA-4), are critical inhibitory receptors expressed on immune cells, particularly T cells, that drive immunosuppressive signaling pathways. However, the potential role of immune checkpoint molecules expression in T-cells on udder health has never been explored. Thus, the association between the occurrence of new postpartum intramammary infections (IMIs) and the expression of programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) on blood T-cells during the peripartum period was investigated. RESULTS: In this study, the incidence of IMIs by any pathogen in early lactation was not associated with a higher expression of PD-1 and CTLA-4 in the periparturient period. However, the incidence of IMIs by major pathogens throughout the first month of lactation was significantly associated with higher expression of PD-1 at 14 days before calving (P = 0.03) and CTLA-4 at parturition (P = 0.03) by blood T-cells. Also, the expression of CTLA-4 at D0 (P = 0.012) by T-cells was associated with the occurrence of persistent IMIs during the first month of lactation. CONCLUSIONS: To our knowledge, this is the first report to investigate the expression of PD-1 and CTLA-4 by blood T-lymphocytes during the periparturient period in dairy cows and to explore their relationship with the incidence of new IMIs in the postpartum period. Thus, a comprehensive understanding of leukocyte biology during peripartum would appear to be a prerequisite for the identification of resilient dairy cows or targets innovative (immunological) non-antibiotic approaches in the transition period.

Conmemorando los cincuenta años de Leche Purita: importancia de la leche en la erradicación de la desnutrición infantil en Chile

La desnutrición ocurre cuando hay una ingesta o asimilación deficiente de la energía y los nutrientes. Si esta se produce dentro de los primeros años de vida, las consecuencias para la salud son devastadoras. El tratamiento temprano de la desnutrición es clave para reducir estas consecuencias y en este proceso la leche tiene una participación destacada. La leche es un excelente alimento debido al contenido y calidad de sus macro- y micronutrientes, lo que ha llevado a que la investigación y el uso de la leche en el tratamiento de la desnutrición hayan aumentado sostenidamente desde comienzos del siglo XX. En Chile, la desnutrición infantil fue prácticamente erradicada entre los años 1960 y 1980 debido a la aplicación exitosa de una serie de políticas públicas materno-infantiles, dentro de las cuales la Leche Purita fue fundamental. Sin embargo, la historia de la leche como parte de las políticas nutricionales en Chile comenzó mucho antes. Conmemorando los cincuenta años desde el nacimiento de Leche Purita, el objetivo de este trabajo es realizar un breve repaso acerca de la importancia histórica de la leche en las políticas nutricionales en Chile, enfatizando la contribución realizada por la Leche Purita a la erradicación de la desnutrición infantil y a la disminución de la anemia en niños.

Undernutrition occurs when there is poor intake or assimilation of energy and nutrients. If undernutrition is established within the first years of life, the health consequences are devastating. Early treatment of undernutrition is critical to reduce these consequences and milk plays an important role in this treatment. Cow's milk is an excellent food due to the content and quality of its macro- and micronutrients. This has led to a steady increase in research and the use of milk in treating undernutrition since the beginning of the 20th century. In Chile, child undernutrition was practically eradicated between the decades of 1960 and 1980 due to the successful application of maternal and child public policies, within which the product Leche Purita was fundamental. However, the history of milk as part of nutritional policies in Chile began much earlier. Commemorating fifty years since the introduction of Leche Purita, we aim to summarize the historical importance of milk in Chile's nutritional policies. We emphasize Leche Purita's role in eradicating child undernutrition and reducing anemia among children.

IMU Auto-Calibration Based on Quaternion Kalman Filter to Identify Movements of Dairy Cows.

This work is focused on developing a self-calibration algorithm for an orientation estimation of cattle movements based on a quaternion Kalman filter. The accelerometer signals in the earth's frame provide more information to confirm that the cow is performing a jump to mount another cow. To obtain the measurements in the earth's frame, we propose a self-calibration method based on a strapdown inertial navigation system (SINS), which does not require intervention by the user once deployed in the field. The self-calibration algorithm uses a quaternion-based Kalman filter to predict the angular orientation with bias correction, and update it based on the measurements of accelerometers and magnetometers. The paper also depicts an alternate update to adjust the inclination using only the accelerometer measurements. We conducted experiments to compare the accuracy of the orientation estimation when the body moves similarly to cow mount movements. The comparison is between the proposed self-calibration algorithm with the IvenSense MPU9250 and Bosch BNO055 and the quaternion attitude estimation provided in the BNO055. The auto-calibrating algorithm presents a mean error of 0.149 rads with a mean consumption of 308.5 mW, and the Bosch algorithm shows an average error of 0.139 rads with a mean consumption of 307.5 mW. When we executed this algorithm in an MPU9250, the average error was 0.077 rads, and the mean consumption was 277.7 mW.

Human proinsulin production in the milk of transgenic cattle.

BACKGROUND: The worldwide growing demand for human insulin for treating diabetes could be supplied by transgenic animals producing insulin in their milk. METHODS AND RESULTS: Pseudo-lentivirus containing the bovine ß-casein promoter and human insulin sequences was used to produce modified adult fibroblasts, and the cells were used for nuclear transfer. Transgenic embryos were transferred to recipient cows, and one pregnancy was produced. Recombinant protein in milk was evaluated using western blotting and mass spectrometry. One transgenic cow was generated, and in milk analysis, two bands were observed in western blotting with a molecular mass corresponding to the proinsulin and insulin. The mass spectrometry analysis showed the presence of human insulin more than proinsulin in the milk, and it identified proteases in the transgenic milk that could convert proinsulin into insulin and insulin-degrading enzyme that could degrade the recombinant protein. CONCLUSION: The methodologies used for generating the transgenic cow allowed the detection of the production of recombinant protein in the milk at low relative expression compared to milk proteins, using mass spectrometry, which was efficient for detecting recombinant protein with low expression in milk. Milk proteases could act on protein processing converting recombinant protein to functional protein. On the other hand, some milk proteases could act in degrading the recombinant protein.

Supplementation with long-acting injectable progesterone 3 days after TAI impaired luteal function in buffaloes.

Three experiments were conducted to evaluate the effects of long-acting injectable progesterone (iP4) in buffalo cows. In Experiment 1, ovariectomized buffaloes received 300 mg (iP300) or 600 mg (iP600) of iP4, and serum P4 concentrations were evaluated. In experiment 2, three groups were compared: control or administration of 300 mg of iP4 3 (iP4-D3) or 6 days (iP4-D6) after timed artificial insemination (TAI). On day 16, reproductive tract was recovered for conceptus, endometrium, and corpus luteum (CL) analysis. In experiment 3, pregnancy per AI (P/TAI) and proportion of pregnancy losses were evaluated after administration of 300 mg of iP4 3 (iP4-D3) or 6 days (iP4-D6) after TAI in lactating buffaloes. In experiment 1, serum P4 concentrations remained over 1 ng/mL for ~ 3 days in both groups. The 300 mg dose was used in subsequent experiments. In experiment 2, CL weight and endometrial glands density were decreased, and conceptus length was increased in iP4-D3 compared to control and to iP4-D6 (P < 0.05). Transcript abundance of Prostaglandin F Receptor (FP) and ISG15 in CL and of ISG15 and MX1 in endometrium was greater in iP4-D3 when compared to control and to iP4-D6 (P < 0.05). In experiment 3, there was no difference among experimental groups for P/TAI at D30 and pregnancy losses (P > 0.1); however, iP4-D3 presented a lower P/TAI at day 60 (41.7%) when compared to control (56.8%) and iP4-D6 (57.7%; P = 0.07). In conclusion, administration iP4 at 3 days after TAI affects CL development and consequently decreases final pregnancy outcome in buffaloes.

Longitudinal genetic dynamics of weaning index and implications for cow-calf production efficiency.

In beef cattle, the selection for higher weights at young ages has been questioned with the argument that this criterion may increase the adult weight of cows, resulting in higher costs. Therefore, selection criteria should be employed to increase weights at young ages with minimal impact on the adult weight of cows. Additionally, the relationship between measures of cow production efficiency and other well-established selection criteria in breeding programs remains poorly understood. The objective of this study was to longitudinally evaluate the relationship between the weaning index (WIndex) as a measure of efficiency and growth traits of the cows. Possible changes over time in WIndex due to selection applied for yearling weight (YW) were also investigated. The WIndex was proposed to maximize genetic response in the weaning weight of the calf while maintaining genetic gain in BW of the cow at zero. A random regression model was adopted to estimate correlations between WIndex, BW, hip height (HH), and body condition score (BCS) using records of Nelore cows from three lines. Genetic trends were calculated for the control line (NeC) and lines selected for greater YW (NeS and NeT). The age of 3 years was the most critical for the weaning efficiency of the cows. At this stage, young cows are still growing and wean lighter calves than their adult counterparts. The genetic correlation estimates between WIndex and BW (-0.58 to 0.04), HH (-0.05 to -0.34), and BCS (-0.51 to -0.17) were close to zero or negative. BW and HH were strongly correlated genetically across all ages (0.73-0.76). In general, HH exhibited a weak and negative genetic relationship with BCS. The genetic correlation between BW and BCS was stronger for advanced ages (0.45-0.68). In lines selected for YW, important increases in WIndex were observed. However, NeS has been selected since the 1980s until the present for YW, and thus, it showed a more pronounced trend of increasing BW and, consequently, a more modest trend of increasing WIndex compared to NeT. In contrast, WIndex exhibited a trend close to zero for NeC. In this context, monitoring HH and BCS can be useful to avoid losses in the weaning efficiency of cows. Furthermore, we suggest that one way to mitigate efficiency losses in calf production could involve stabilizing the BW of cows and increasing the weaning weight of calves using the WIndex.