RESUMO
Calf management and health are essential for setting up the foundation of a productive cow. The objectives of this study were to estimate the impact of preweaning practices on milk production parameters while accounting for an animal's genetic potential in New Brunswick, Canada. A retrospective cohort study was performed on 220 heifer calves from eight herds born in 2014-2015. Preweaning practices and health data were recorded by producers and reviewed by the herd veterinarian for each calf. The herd veterinarian also visited the farms to collect serum samples from calves and frozen colostrum samples. The production outcomes assessed were milk, protein and fat yields, standardized to 305 d for the first lactation (L1) and a combined group of lactations two and three (L2â +â 3). The genomic potential was determined as genomic parent averages (GPA) for the associated production parameters. Analysis was performed with multivariable linear (L1) and linear mixed (L2â +â 3) regression models. In L1, for every 1.0 kg increase in weaning weight, milk, protein, and fat yield increased by 25.5, 0.82, and 1.01 kg, respectively (Pâ <â 0.006). Colostrum feeding time (CFT) positively impacted L1 milk and protein production, with feeding between 1-2 h of life producing the greatest estimates of 626 kg of milk and 18.2 kg of protein yield (Pâ <â 0.007), compared to earlier or later CFT. Fat yield production was decreased by 80.5 kg (Pâ <â 0.006) in L1 when evaluating animals that developed a preweaning disease and were not treated with antibiotics compared to healthy untreated animals. Impacts on L2â +â 3 were similar across all production outcomes, with a positive interaction effect of CFT and weaning weight. Compared to CFTâ <â 1 h, the later CFT groups of 1-2 h andâ >â 2 h produced greater yield outcomes of 68.2 to 72.6 kg for milk (Pâ <â 0.006), 2.06 to 2.15 kg for protein (Pâ <â 0.005), and 1.8 to 1.9 kg for fat (Pâ <â 0.045) for every 1 kg increase of weaning weight, respectively. The fit of all models was significantly improved with the inclusion of GPA. These results indicate that colostrum management and preweaning health measures impacted production parameters as adults. The inclusion of GPA significantly improved the accuracy of the models, indicating that this can be an important parameter to include in future studies.
The impact of calf management and health events have been predominately investigated during the preweaning period. However, calfhood events could also impact the animal's health and productivity as an adult. Results from this study indicate that colostrum feeding time and weaning weight were associated with production outcomes (milk, protein, and fat yields) across the first three lactations, and disease and antibiotic treatment can be detrimental to fat yield in the first lactation. By including genetic potential in the assessment of preweaning colostrum practices and health measures on production outcomes, we can more precisely identify areas to optimize calf management.
Assuntos
Colostro , Indústria de Laticínios , Humanos , Gravidez , Bovinos , Animais , Feminino , Estudos Retrospectivos , Indústria de Laticínios/métodos , Leite/metabolismo , Lactação , DesmameRESUMO
This research paper analyzes the stability of raw cow milk in the alcohol test and seeks to understand to know the factors that influence milk stability and the occurrence of unstable non-acid milk. Milk samples were collected from the cooling tanks of rural farmers in the state of Paraná twice in summer and twice in winter. The farms were classified according to the production system: pasture with supplementation and feedlot. The following variables were analyzed: stability in the alcohol test, titratable acidity, ionized calcium concentration (iCa), chemical composition of milk, somatic cell count and standard plate count. The results showed that milk stability was greater in winter vs. summer, when the milk contained higher iCa, and in the feedlot vs. pasture system. The Pearson Correlation between variables (ethanol stability, milk composition, iCa, cooling tank temperature, milk volume, number of milking, number of cows milked, fat/protein ratio, distance and travel time) were analyzed. Stability was negatively correlated with iCa concentration and positively with lactose content. Logistic regression of the risk of unstable non-acid milk at 72% alcohol (UNAM72) showed that only iCa and lactose were determinants, while evaluation of the same risk at 78% alcohol revealed iCa, titratable acidity, lactose and milk urea nitrogen as risk factors. Under the dairy farming conditions of Paraná state, the frequency of UNAM72 was low (12.16%) and was higher in summer and in pasture systems with supplementation. In conclusion, in dairy herds bred with high technological level, with adequate nutritional and health management, the frequency of UNAM is low and is related to nutritional management abnd, perhaps, heat stress, factors that alter iCa and lactose levels.
Assuntos
Indústria de Laticínios , Leite , Estações do Ano , Animais , Leite/química , Bovinos , Feminino , Indústria de Laticínios/métodos , Cálcio/análise , Lactose/análise , Etanol/análise , Concentração de Íons de Hidrogênio , Contagem de Células/veterináriaRESUMO
Diet formulation in a pasture-based dairy system is a challenge as the quality and quantity of available pasture, which generally constitutes the base diet, is constantly changing. The objective of this paper is to cover a more in-depth review of the nutritional characteristics of pasture-based diets, identifying potential system, plant, and animal factors that condition pasture dietary inclusion in dairy cows. In practice, there is a wide diversity of pasture-based systems with predominant to minimal use of pasture requiring a more specific classification that potentially considers the amount and time of access to pasture, access to housing, length of grazing season, seasonality of calving, and level and method of supplementation. There are important differences in the nutritional quality between pasture species and even cultivars. However, under management practices that promote maintenance of pasture in a vegetative state as well as controlling the availability of pasture, it is possible to achieve high dry matter intakes (â¼2.9%-3.4% of live weight) of pasture with moderate to high diet energy density, protein supply, and digestibility. The amount of pasture to include in the diet will depend on several factors, such as the type of production system, the cost of supplementary feeds, and the farmer's objectives, but inclusions of â¼40% to 50% of the diet seem to potentially reduce costs while apparently not limiting voluntary feed intake. Considering that there seems to be a continuum of intermediate management systems, a better understanding of the factors inherent to the feed ingredients used, as well as the use of nutrients by cows, and potential interactions between animal × system should be addressed in greater depth. This requires a meta-analysis approach, but given the diversity of the pasture-based system in practice, the existing information is highly fragmented. A clear definition of "subsystems" is necessary to direct the future research and development of mechanistic models.
Assuntos
Lactação , Leite , Animais , Bovinos , Feminino , Humanos , Ração Animal/análise , Indústria de Laticínios/métodos , Dieta/veterinária , Ingestão de Alimentos , Leite/metabolismoRESUMO
This study aimed to evaluate the HerbValo method in comparison to conventional field measurement techniques as a tool for estimating the herbage utilization and dry matter (DM) intake by grazing dairy cows under subtropical conditions. It was carried out during 18 months in a commercial farm of Southern Brazil. The herbage utilization was estimated monthly in two to four randomly selected paddocks (total n = 40) using the rising-plate meter or the double-sampling technique. In parallel, the herbage utilization was estimated by the HerbValo method, which is based on simple descriptions of the herd, supplements, pasture and grazing management. Values of herbage utilization estimated by field techniques were linearly (P < 0.01) related to those estimated by HerbValo, with no effect of pasture type (tropical vs. temperate) on the origin or on the slope of the regression (slope = 0.97; origin = -0.1; R2 = 0.81; rsd = 0.17 t DM/ha). At cow × day level, values of herbage intake estimated by field techniques were also linearly related to those estimated by HerbValo (P < 0.01; R2 = 0.82; rsd = 1.30 kg DM/cow/day). A negative linear relationship (P < 0.01) between herbage and supplement intake was obtained for both field (slope = -1.06; R2 = 0.72; rsd = 1.64) and HerbValo (slope = -0.92; R2 = 0.82; rsd = 1.08) approaches. Herbage utilization and intake by a dairy herd in a subtropical grazing-based system can be reliably estimated by the HerbValo method with the advantage of not requiring direct field pasture measurements.
Assuntos
Lactação , Leite , Feminino , Bovinos , Animais , Ração Animal , Suplementos Nutricionais , Brasil , Dieta/veterinária , Indústria de Laticínios/métodosRESUMO
This study used realistic evaluation to determine how, and in which circumstances, providing dairy farmers with benchmarked data on their calves can motivate improved colostrum management practices. Dairy farmers from British Columbia, Canada, were recruited through 2 veterinary clinics that offered benchmarking of calf data as part of their services. For approximately 8 wk, blood samples were collected from newborn calves to evaluate serum total protein concentrations as an indicator of the effectiveness of the farmer's colostrum management. These data were analyzed separately for heifer calves ("replacement calves") and non-replacement calves, including males and beef crossbred females ("surplus calves"). The results of these analyses were benchmarked against other participating herds and presented to dairy farmers (n = 27) by their herd veterinarian (n = 7). Follow-up interviews were conducted separately with the farmers and veterinarians after each meeting to determine their perspectives on the utility of this benchmarking strategy. Therefore, a total of 42 interviews were coded, and realistic evaluation was used to determine common contexts and mechanisms that contributed to the success or failure of the benchmark meeting, with success characterized by farmers' expressed intention to improve their colostrum management practices. Four important contexts were identified that influenced the outcome of the benchmark meetings: (1) farm resources (e.g., facility limitations), (2) the farmer's perception of their calf performance, (3) management strategies, and (4) the farmer's personal values. Depending on these contexts, some farmers intended to improve their calf care practices based on resources the benchmark meeting provided, which included illustrative data and veterinary advice. These resources motivated change through influencing farmer decision-making, which depended on the value they saw in the data as a decision-making tool. The economic or moral interest farmers expressed in their surplus calves also influenced whether farmers intended to implement management changes. Recommendations for future implementation of benchmarking include targeting producers who are motivated to improve and who value the future performance of their calves, those who have engaged calf care personnel, and those who prefer data-driven decision-making. This study supports the important role veterinarians can play in motivating improved calf care practices through providing benchmarking services.
Assuntos
Colostro , Indústria de Laticínios , Animais , Bovinos , Feminino , Masculino , Gravidez , Colúmbia Britânica , Indústria de Laticínios/métodos , FazendasRESUMO
In recent years, the common dairy farming practice of early separation of dam and calf has received increased attention. Our aim was to explore how Norwegian dairy farmers with cow-calf contact (CCC) systems apply these systems in practice, and how they experience and perceive the interrelationships between cows and calves and humans within these systems. We conducted in-depth interviews with 17 farmers from 12 dairy farms and analyzed responses inductively, inspired by the grounded theory approach. The farmers in our study practiced their CCC systems differently from each other and had varying as well as common perceptions about these systems. Calves' intake of colostrum was not seen as a challenge, regardless of practice. The farmers generally perceived that any aggression shown by cows toward humans was merely an exhibition of cows' natural protective instinct. However, when the farmers had good relationships with their cows and the cows felt safe around them, the farmers could handle the calves and build good relationships with them as well. The farmers experienced the calves learning a lot from their dams. Most of the farmers' dairy housing systems were not adapted for CCC, and CCC systems could require modification in terms of placing greater emphasis on observing the animals and making adjustments in the barn and around milking. Some thought having CCC on pasture was the best and most natural, while others were reluctant to have CCC on pasture. The farmers encountered some challenges with stressed animals after later separation, but several had found methods to minimize stress. Generally, they had different opinions about workload, but agreed they spent less time on calf feeding. We found that these farmers were thriving with their CCC systems; they all described positive emotions around seeing cows and their calves together. Animal welfare and natural behavior were important to the farmers.
Assuntos
Indústria de Laticínios , Fazendeiros , Humanos , Gravidez , Feminino , Animais , Bovinos , Indústria de Laticínios/métodos , Colostro , Noruega , Pesquisa QualitativaRESUMO
The objective of this narrative review was to compare the results of the 2015 Canadian National Dairy Study and the 2014 US National Animal Health Monitoring System (NAHMS) Dairy Studies, with a specific focus on calf management and welfare, and to interpret these findings within more recent calf health research to describe where we need to go next in the North American dairy industry. Situating results of periodic national studies within the context of past and recent research provides an opportunity to gauge adoption of recommendations and best practices and to help identify persistent and new challenges that the industry is wrestling with to help guide research needs. Through this review of the 2 national studies, we identified several strengths of the Canadian and US dairy industries. In each area of calf health management, improvements relative to previous NAHMS studies and the published literature have been found in the level of mortality, amount of colostrum fed, housing, and the number of producers using pain control for disbudding and dehorning. There were, however, some areas that present clear opportunities for improvement. Specifically, although mortality levels have improved, a large number of calves die at birth, within the first 48 h of life, and during the preweaning period. To improve the health of calves in early life, producers could look at feeding high-quality colostrum at 10% of body weight in the first feeding, as well as feeding a larger amount of milk during the preweaning period. The barriers to making these management changes and improving overall calf health need to be identified in future studies. The majority of preweaning calves in Canada and the United States are housed in individual housing. This represents a clear opportunity for improvement because recent research has identified the positive aspects of group housing. Finally, with respect to pain control, improvements are needed (particularly in the United States) to ensure that pain management is provided when disbudding and dehorning calves. Although the science is clear on pain management, discussions with producers are needed to identify reasons for the lack of uptake.
Assuntos
Colostro , Indústria de Laticínios , Gravidez , Feminino , Animais , Bovinos , Estados Unidos , Canadá , Indústria de Laticínios/métodos , Leite , Dor/veterinária , DesmameRESUMO
Lack of experience concerning the organic conversion period and its associated challenges have made it difficult for conventional farmers to convert to organic farming. In this study, using a combined life cycle assessment (LCA) with data envelopment analysis (DEA) approach, we investigated farming management strategies, and environmental, economic, and efficiency impacts of organic conversion tea farms (OCTF, N = 15) compared to conventional (CTF, N = 13) and organic (OTF, N = 14) tea farms in Wuyi County, China for a year-round (2019). We found that the OCTF reduced agricultural inputs (environmental impacts) and applied more manual harvesting (increased added value) to pull through the conversion period. According to the LCA results, OCTF showed a similar integrated environmental impact index compared with OTF but significantly (P < 0.05) lower than CTF at both midpoint and endpoint levels. In terms of economic assessment, OTF showed the significantly highest total revenue (18.7 thousand $ ha-1 yr-1) and profit (13.7 thousand $ ha-1 yr-1) (P < 0.05) among the farm types. In contrast, OCTF and CTF did not show significant differences in relation to these economic indicators (P > 0.05). The total cost and cost-profit ratio did not show significant differences among the three farm types. Considering the DEA analysis, there were no significant differences in the technical efficiency of all farm types. However, the eco-efficiency of OCTF and OTF was significantly higher than that of CTF. Therefore, conventional tea farms can survive the conversion period with competitive economic and environmental benefits. In this regard, policies should promote organic tea cultivation and agroecological practices to enhance the sustainable transformation of tea production systems.
Assuntos
Indústria de Laticínios , Agricultura Orgânica , Fazendas , Indústria de Laticínios/métodos , Meio Ambiente , Agricultura/métodos , China , CháRESUMO
The primary objective of this study was to compare male and female dairy calf management practices and evaluate risk factors associated with differences in care. Secondary objectives were to understand surplus calf transportation and marketing practices and investigate incentives to motivate calf care improvements. An online survey was distributed to all dairy producers in Ontario (n = 3,367) from November 2020 to March 2021 and Atlantic Canada (n = 557) from April to June 2021. Dairy producers were identified through provincial dairy associations and contacted via e-mail and social media. Descriptive statistics were computed, and a logistic regression model was created to evaluate factors associated with using discrepant feeding practices (i.e., fed less colostrum, fed colostrum later, or fed raw, unsalable milk) for male calves compared with females. The survey had a 7.4% response rate (n = 289/3,924) and was primarily filled out by farm owners (76%). Although colostrum and milk feeding practices were similar between male and female calves, male calves received less milk while still on the dairy farm of origin compared with females. Male calves were also more likely to be fed a higher proportion of raw, unsalable milk. Female producers and those that kept their male calves beyond 10 d of age had lower odds of using poorer feeding practices for male calves. Male calves were mostly sold between 1 and 10 d (64%), primarily through direct sales to a calf-rearing facility (45%), with auctions being the next most common method (35%). A small but notable proportion of producers (18%) agreed that euthanizing male calves is a reasonable alternative when their sale price is very low; however, few producers (13%) reported that financial costs limited their male calf care. The largest proportion (43%) of producers reported that a price premium for more vigorous calves would motivate them to take better care of their male calves. Conversely, only 28% of producers reported that a price discount for calves in poor condition would be motivating. Producers placed importance on the opinion of their calf buyer, their herd veterinarian, and the Canadian Code of Practice for the Care and Handling of Dairy Cattle when considering their calf care practices, and they highly valued practices that promote calf health. Respondents to this survey reported a lower proportion of tiestall barn use and higher milk productivity compared with typical dairy herds in the region, suggesting selection bias for more progressive dairy producers. Nevertheless, our results suggest that dairy producers provide similar care between male and female calves, but some male calves experience challenges due to milk feeding and marketing practices. Feedback from calf buyers along with continued support and guidance from herd veterinarians and the Code of Practice may motivate dairy producers to improve male calf care.
Assuntos
Colostro , Indústria de Laticínios , Gravidez , Bovinos , Animais , Masculino , Feminino , Indústria de Laticínios/métodos , Leite , Fazendas , Inquéritos e Questionários , OntárioRESUMO
The objective of this study was to assess hepatic ATP synthesis in Holstein cows of North American and New Zealand origins and the gluconeogenic pathway, one of the pathways with the highest ATP demands in the ruminant liver. Autumn-calving Holstein cows of New Zealand and North American origins were managed in a pasture-based system with supplementation of concentrate that represented approximately 33% of the predicted dry matter intake during 2017, 2018, and 2019, and hepatic biopsies were taken during mid-lactation at 174 ± 23 days in milk. Cows of both strains produced similar levels of solids-corrected milk, and no differences in body condition score were found. Plasma glucose concentrations were higher for cows of New Zealand versus North American origin. Hepatic mitochondrial function evaluated measuring oxygen consumption rates showed that mitochondrial parameters related to ATP synthesis and maximum respiratory rate were increased for cows of New Zealand compared with North American origin. However, hepatic gene expression of pyruvate carboxylase, phosphoenolpyruvate carboxykinase, and pyruvate dehydrogenase kinase was increased in North American compared with New Zealand cows. These results altogether suggest an increased activity of the tricarboxylic cycle in New Zealand cows, leading to increased ATP synthesis, whereas North American cows pull tricarboxylic cycle intermediates toward gluconeogenesis. The fact that this occurs during mid-lactation could account for the increased persistency of North American cows, especially in a pasture-based system. In addition, we observed an augmented mitochondrial density in New Zealand cows, which could be related to feed efficiency mechanisms. In sum, our results contribute to the elucidation of hepatic molecular mechanisms in dairy cows in production systems with higher inclusion of pastures.
Assuntos
Gluconeogênese , Lactação , Trifosfato de Adenosina/metabolismo , Animais , Bovinos , Indústria de Laticínios/métodos , Dieta/veterinária , Feminino , Expressão Gênica , Gluconeogênese/genética , Lactação/genética , Leite/metabolismo , Mitocôndrias/metabolismoRESUMO
BACKGROUND: Nursery farms that accept nursing and growing pre-weaned heifer calves from private dairy farms must work to prevent bovine respiratory disease (BRD). Knowledge of the BRD-associated risk factors related to calf management and calves' condition will help to develop appropriate neonatal management practices at original farms and to identify calves at higher risk for BRD at nursery farms. In this study, the relationship between BRD and calf management practices (colostrum feeding, dam parity, serum total protein concentration at introduction (TP), body weight at introduction, introduction season, and daily average growth) was investigated using observational data from pre-weaned dairy calves introduced into a nursery farm in Hokkaido, Japan between 2014 and 2018 (n = 3185). Using additive Bayesian network (ABN) analysis, which is a multivariate statistical modelling approach, the direct and indirect associations between these factors were assessed. RESULTS: Colostrum feeding contributed to an increase in TP (correlation 1.02 [95 % CI, 0.94;1.10]), which was negatively associated with BRD directly (log odds ratio - 0.38 [- 0.46;-0.31]) and indirectly through increasing daily growth (correlation 0.12 [0.09;0.16]). Calves of multiparous dams had higher body weight at introduction (correlation 0.82 [0.74;0.89]), which indirectly reduced BRD risk through the increasing daily growth (correlation 0.17 [0.14;0.21]). Calves introduced during winter had the highest risk for BRD (log odds ratio 0.29 [0.15;0.44]), while those introduced in summer had the lowest risk (log odds ratio - 0.91 [- 1.06;-0.75]). The introduction season was also associated with BRD indirectly through dam parity, body weight at introduction, and daily growth. CONCLUSIONS: The following calf management practices are recommended for preventing BRD in pre-weaned calves at nursery farms: (1) encouraging colostrum feeding to neonatal calves at their original farms; and (2) identifying calves with higher BRD risk, i.e., those without feeding colostrum, born to primiparous cattle, with low body weight at introduction, and/or introduced in winter, and paying intensive attention to the calves for rapid detection of BRD. ABN analysis applied enabled us to understand the complex inter-relationships between BRD incidence and the risk factors, which will help to reduce BRD incidence and to rear healthy calves at nursery farms.
Assuntos
Criação de Animais Domésticos/métodos , Complexo Respiratório Bovino/epidemiologia , Dieta/veterinária , Animais , Animais Recém-Nascidos , Teorema de Bayes , Peso ao Nascer , Complexo Respiratório Bovino/prevenção & controle , Bovinos , Colostro , Indústria de Laticínios/métodos , Feminino , Japão/epidemiologia , Estações do AnoRESUMO
The results of most studies show the beneficial effect of milking automation on production parameters of dairy cows, but its effect on fertility traits is debatable. Therefore, a study was undertaken to predict cow fertility - services per conception (SC) and calving interval (CI) - based on automatic milking system (AMS) data collected in the periparturient period subdivided into the second and first week before calving, 1-4, 5-7, 8-14, 15-21 and 22-28 days of lactation. SC and CI were predicted using daily indicators such as concentrate intake, number of milkings, cow box time, milking time, milking speed, colostrum and milk yield, composition, temperature and electrical conductivity. The study material was derived from the AMS management system and from the SYMLEK milk recording system. The analysis covered data for 16,329 milkings of 398 Polish Holstein-Friesian (PHF) cows, which were used in three AMS herds. The collected numerical data were statistically analysed by correlation analysis in parallel with decision tree technique (SAS statistical package). The present study showed that due to the low, mostly non-significant coefficients of correlation between AMS data collected between 2 weeks before and 4 weeks after calving, it is not possible to predict cow fertility based on single traits. It has been established that the decision tree method may help breeders, already during the postcalving period, to choose the level of factors associated with AMS milking, which will ensure good fertility of cows in a herd. The most favourable number of services per conception is to be expected from cows that were milked <1.6 times per day from 1 to 4 days of lactation and electrical conductivity of their colostrum did not exceed 69 mS during that time. In turn, shortest CI (366 days) will be characteristic of the cows whose average daily colostrum yield did not exceed 20.2 kg and their daily concentrate intake from 8 to 14 days of lactation was at least 5.0 kg.
Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Fertilidade , Animais , Colostro , Indústria de Laticínios/instrumentação , Comportamento Alimentar , Feminino , Lactação , Leite/estatística & dados numéricos , GravidezRESUMO
We investigated and compared the effects of low and high concentrate supplementation in terms of animal welfare, health and reproductive performance in two different dairy cow breeds on small-scale mountain farms. 64 South Tyrolean dairy farms were evaluated using an on-farm assessment for animal-based and resource-based welfare indicators, data from test day records, and a questionnaire for the farmer. Farms were divided into four groups: low input Tyrolean Grey (L-TG), low input Brown Swiss (L-BS), high input Tyrolean Grey (H-TG) and high input Brown Swiss (H-BS). Effects of intensity level, breed and their interaction were calculated and analyzed statistically. The predominant husbandry system across all groups was tie-stall. The average energy-corrected milk yield increased with increasing concentrate level, with L-TG showing the lowest and H-BS showing the highest milk yield. Age at first calving was lowest in H-BS when compared to all other systems, while numbers of lactations were higher in L-TG compared to H-BS. Feed efficiency (percentage of milk out of roughage) was significantly higher in L-TG and L-BS when compared to H-TG and H-BS. L-BS showed the poorest results for most of the welfare indicators such as lean cows, lesions and percentage of dirty animals. In conclusion, a higher concentrate level in diets does not lead automatically to lower animal welfare for dairy cows in alpine regions. Indeed, keeping high yielding breeds in extensive systems seems to be challenging. The dual-purpose breed TG showed some clear advantages in that calving interval was lower and the number of lactations greater.
Assuntos
Ração Animal , Bovinos/fisiologia , Indústria de Laticínios/métodos , Fazendas , Lactação/fisiologia , Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Fazendeiros , Feminino , Nível de Saúde , Gravidez , Reprodução/fisiologia , Especificidade da EspécieRESUMO
In this study it is hypothesized that there are differences between immunoglobulin G (IgG) content in colostrum from beef (Chianina, Podolica) and dairy (Holstein Friesian) cows and that variables such as breed, and parity can influence IgG content. The further objective was to determine if these factors may vary in terms of sensitivity, specificity and the cut point when data obtained with the digital Brix refractometer is compared with the gold standard radial immunodiffusion assay (RID). A total of 90 samples of first-milking colostrum were collected within 2 h after parturition. IgG concentration was determined indirectly by digital Brix refractometer and directly by RID. Results obtained by RID were compared among breed and parity. For the digital Brix refractometer, sensitivity and specificity to detect colostrum with an IgG concentration lower than 50 g/l were calculated and the optimal cut-point was selected for each breed. Samples containing less than <50 g/l IgG accounted for 15.9% of the total. Parity influenced colostral IgG concentration and beef cows had a higher mean concentration of IgG (101.1 g/l in Chianina and 90.6 g/l in Podolica) than dairy cows (71.1 g/l in Holstein Friesian) First parity Chianina cows had the highest IgG mean content (116.1 g/l). At the optimal cut-point for Brix refractometer (20%) sensitivity and specificity were 0.93 (0.84-0.97) and 0.81 (0.70-0.88), however, a breed-related cut-point could be used to reduce evaluation error. Linear regression modeling showed that refractometer data were related to RID (r = 0.78). Results obtained suggest that breed and parity can influence IgG content of colostrum and, despite the Brix refractometer being an excellent on-farm tool, a breed-based definition of optimal cut point is needed.
Assuntos
Bovinos/imunologia , Colostro/imunologia , Imunoglobulina G/análise , Refratometria/veterinária , Agricultura/métodos , Animais , Indústria de Laticínios/métodos , Feminino , Itália , Carne Vermelha , Refratometria/instrumentação , Sensibilidade e EspecificidadeRESUMO
This research communication addressed the hypothesis that late lactation cows offered an oat-grain-based supplement or a high level of α-TOC supplementation at pasture would have improved milk composition and processability. Over a grazing period of 49 d, 48 Holstein Friesian dairy cows were randomly assigned to one of four dietary treatments. The dietary treatments were: control, pasture only (CTRL), pasture + 2.65 kg DM barley-based concentrate + 350 IU α-TOC/kg (BARLO), pasture + 2.65 kg DM oat-based concentrate + 350 IU α-TOC/kg (OATLO) and pasture + 2.65 kg DM oat-based concentrate + 1050 IU α-TOC/kg (OATHI). Within this randomised complete block design experiment cows were blocked on days in milk (DIM) and balanced for parity, milk yield and composition. Rennet coagulation time (RCT) was reduced in milk from cows offered OATHI compared to CTRL cows and OATLO. Concentration of conjugated linoleic acid (CLA) was increased by OATHI compared to OATLO and in OATLO compared to CTRL. Supplementation with OATHI reduced individual saturated fatty acids (SFAs) in milk compared to OATLO. In conclusion, supplementing grazing dairy cows with an oat-based supplement improved total milk CLA concentration compared to pasture only. Offering a high level of α-TOC (2931 IU/d) to dairy cows reduced RCT, individual SFA and increased total CLA concentration of milk compared to a lower α-TOC level (738 IU α-TOC/d).
Assuntos
Bovinos/fisiologia , Grão Comestível , Lactação/fisiologia , Leite/química , alfa-Tocoferol/administração & dosagem , Ração Animal/análise , Animais , Avena , Indústria de Laticínios/métodos , Dieta/veterinária , Suplementos Nutricionais , Ácidos Graxos/análise , Feminino , Hordeum , Ácidos Linoleicos Conjugados , LoliumRESUMO
The dairy industry in Senegal is growing and evolving against a backdrop of rapid urbanisation and increasing consumer demand for dairy products. Consideration of appropriate cattle healthcare delivery and disease control in these evolving farming systems is of paramount importance given the risks posed by zoonotic pathogens and the economic consequences of disease for livestock keepers. Planning and implementation of disease control and healthcare delivery generally follows a top down approach. Often this does not take into account the views and perceptions of the farmers it impacts and who must behave in the expected way for successful outcomes to materialise. In this study, we asked 76 farmers to discuss their experience and opinions of farming milk producing cattle in 11 focus group discussions conducted in two peri-urban areas of Senegal. The objectives were to investigate farmers' perceptions of the current conditions in farming, to understand how these might impact the future direction of this particular system and how this might affect the feasibility and appropriate methods of cattle healthcare delivery and disease control. The data collected were subjected to thematic analysis and four themes were identified; 1. Revered cattle, 2. The changing face of livestock keeping, 3. Powerlessness, 4. Optimism for the future. Farmers in our study had a deep affinity with their cattle, they respected the traditions surrounding cattle keeping at the same time as striving for advances within the system and their animal's productivity. Within strong social groupings and hierarchical structures they recognised the inherent challenges they face but were hopeful and optimistic about growth and opportunity in the future of milk production. A holistic approach to embedding healthcare delivery and disease control within the broader context in which farmers operate may prove successful. This could involve consideration of funding channels for farmers, access to appropriate inputs and utilising the strong community spirit and social norms of farmers to initiate and facilitate change.
Assuntos
Agricultura/métodos , Indústria de Laticínios/métodos , Atenção à Saúde , Fazendeiros/psicologia , Adolescente , Adulto , Animais , Atitude , Bovinos , Fazendas , Feminino , Grupos Focais , Humanos , Gado , Masculino , Pesquisa Qualitativa , Senegal , Inquéritos e Questionários , Adulto Jovem , Zoonoses/prevenção & controleRESUMO
Two experiments were designed to determine the effects of dietary iodine and teat-dipping on the iodine status of dairy cows and their milk. Eight mid-lactation Holstein dairy cows with an initial body weight of 642 ± 62 kg and 145 ± 21 d in milk were studied for 2 periods over 44 d. In period 1, all cows were fed a basal diet supplemented with potassium iodide (KI) (10 mg I/Kg DM) for 8 d with no teat-dipping. In period 2, a pre-milking teat-dipping was applied for 10 d followed by no teat-dipping before milking (udder wash without iodine) and then post-dipping treatment was applied for 5 d. Feeding KI increased concentrations of iodine in serum, urine, and milk (P < 0.05). Switching from the KI supplementation to no iodine addition resulted in an immediate decrease of iodine in serum, urine, and milk (P < 0.05). Post teat-dipping resulted in increased iodine levels in serum, urine, and milk (P < 0.05). However, pre-milking teat-dipping did not affect iodine concentration compared to post-dipping. A 250 mL cup of milk from the control and KI-supplemented diets would provide 29.4% and 68.4%, respectively, of the adult-recommended dietary allowance for iodine. In conclusion, milk iodine concentration could be effectively enhanced by KI supplementation and teat-dipping practices.
Assuntos
Bovinos/fisiologia , Iodo/análise , Iodo/deficiência , Glândulas Mamárias Animais/efeitos dos fármacos , Leite/química , Iodeto de Potássio/administração & dosagem , Animais , Indústria de Laticínios/métodos , Dieta/veterinária , Suplementos Nutricionais , Desinfetantes/administração & dosagem , Feminino , Iodo/administração & dosagem , Estado NutricionalRESUMO
In this Research Reflection we review management practices in small family farms with less than 100 cows. Small farms represent the majority of farms in the EU and the world, and they are of great importance for the economy of a country. On cattle farms, the welfare of calves is of primary importance for the profitability of the herd, and poor management is one of the main factors influencing calf health and survival. Data on the risk factors for calf welfare issues in small-scale farms are limited. For this purpose, the literature data from six world countries were presented and compared, including Serbia and Slovenia where a survey related to the issue was carried out within the COST Action FA1308, DairyCare. Some practices within the following areas in calf management were considered: calving management, care for new-born calves, use of painful procedures, colostrum management, cow-calf separation, calf feeding, weaning, calf housing, and general monitoring. In each of the countries, the health and welfare of calves are threatened by some omissions in rearing practices and the major are related to the new-born calf management, the feeding and watering management, and the application of hygienic measures. Many farmers are well aware of the importance of proper calf rearing; others would need more incentive to improve calf management. Each country should pay attention to the education of farmers about the most common deficiencies in calf management.
Assuntos
Bem-Estar do Animal , Animais Recém-Nascidos/fisiologia , Bovinos , Indústria de Laticínios/métodos , Fazendas , Animais , Áustria , Brasil , Canadá , Doenças dos Bovinos/prevenção & controle , Colostro , Indústria de Laticínios/economia , Dieta/veterinária , Fazendas/economia , Fazendas/estatística & dados numéricos , Abrigo para Animais , Sérvia , Eslovênia , Estados Unidos , DesmameRESUMO
Animal welfare is an essential component of dairy production and several systems exist to evaluate the welfare of dairy cows. Here, we review and compare three well-known systems that operate at farm level from around the world (FARM, Welfare Quality®, and The Code of Welfare) and discuss their advantages and limitations. Despite having some commonalities, the programs evaluate different elements. We also briefly review an emerging system (Integrated Diagnostic Welfare System) that might address some of the shortcomings of the existing systems, especially the possibility of automating the evaluation of animal well-being and identifying any cause of poor welfare. None of the aforementioned systems has been fully validated for their ability to assess animal welfare using independent measurements. The future holds increased attention around the well-being of dairy cows and increased use of sensing technologies. There is an urgent need for dairy welfare evaluation systems that are scientifically validated, holistic, and that can take advantage of the use of sensing technologies to continuously monitor animal welfare.
Assuntos
Bem-Estar do Animal , Bovinos , Indústria de Laticínios/métodos , Fazendas , Avaliação de Programas e Projetos de Saúde , Criação de Animais Domésticos/ética , Criação de Animais Domésticos/métodos , Animais , Indústria de Laticínios/ética , União Europeia , Feminino , Nova ZelândiaRESUMO
The aim of this study was to determine the effect of housing system (or manure management system) and season on manure N recovery and volatilization using an N mass balance. Dietary, milk, and manure N were monitored together with outside temperatures in 6 dairy barns. Three barns were designed as conventional freestalls (cubicle, CUB) with an automatic manure scraper system and concrete floor, in which the gutter in the middle was continuously scraped (every 2-4 h) and the slurry was conveyed toward an open-air concrete pool. The other 3 barns were designed as a loose housing system (HS) with a compost-bedded pack (CB) and conventional confinement housing provided with a feed alley that was cleaned mechanically (2-3 times per day). The farms under study were located near Lleida in the center of the Ebro valley, in northeastern Spain. Nitrogen recovery was measured twice under farm-like conditions either during spring-summer (3 mo of increasing temperatures) or fall-winter (3 mo of decreasing temperatures). The number of cows per barn ranged from 99 to 473, and average age, mean lactation, and parturition intervals were 4.1 yr, 2.43 lactations, and 426.6 d, respectively. In spring-summer, animals ate more [26.3 vs. 23.8 kg of dry matter (DM)/d] and produced more milk (34.6 vs. 31.3 kg/d ± 0.68). However, milk composition did not change. Stored manure from the CB system showed a higher DM concentration with respect to the CUB system (379.15 vs. 97.65 g/kg of fresh matter); however, N (31.45 vs. 40.2), NH3-N (5.3 vs. 18.9) and its ratios with phosphorus (NH3-N:P, 3.52 vs. 5.2) and potassium (NH3-N:K, 0.615 vs. 2.69) showed the opposite trend. No differences were found in N intake (653 vs. 629.5 g/d) or milk N secretion (190 vs. 177.8 g/d for CUB and CB barns, respectively) although net N recovery of the excreted N (Nintake - NMilk) was significantly lower in manure in CB barns than in CUB systems (193.8 vs. 389.3 g/d). The proportion of N irreversible loss in relation to the N intake was higher in CB than in CUB barns (42.3 vs. 11.0%). There was no clear association between season and irreversible N losses; however, the housing system was pivotal in the association between N recovery in manure and irreversible losses by volatilization.