An agent-based simulation model to compare different reproductive strategies in cow-calf operations: Economic performance.

In a companion paper, Ojeda-Rojas et al. (2021) [1] describe a stochastic agent-based simulation (ABS) model of a cow-calf operation on a commercial farm in São Paulo, Brazil. The model's parameterization was based on data collected from two sources: a real beef cattle herd and related scientific literature. Based on the mentioned simulation model, this study aims to assess the economic outcome of 10 different reproductive scenarios: Natural mating only (ONM); one timed artificial insemination (TAI) plus natural mating (NM) (1TAI + NM); two TAI plus NM, with 24, 32, and 40 days between TAI (2TAI/24 + NM, 2TAI/32 + NM, and 2TAI/40 + NM, respectively); three TAI without NM, with 24, 32, and 40 days between TAI (3TAI/24, 3TAI/32, and 3TAI/40, respectively); and three TAI plus NM, with an interval between TAI of 24 (3TAI/24 + NM) and 32 days (3TAI/32 + NM). The simulation was performed on an animal-by-animal basis over a time horizon of 5000 days. Each scenario had 32 farms, and each farm kept up to 400 adult females. According to the scenario, a bull population was composed of 0, 7, or 15 individuals. The outcomes, represented as means ± standard deviations, were assessed after reaching a steady-state (1825 days). The model outcomes showed that the 3TAI/24 + NM scenario resulted in higher incomes (US$ 96,479.19 ± 709.81), whereas the ONM scenario had the lowest incomes (US$ 79,753.37 ± 741.87). The 3TAI/24 + NM (US$ 101.720.63 ± 79.21) and ONM (US$ 90.898.58 ± 59.17) scenarios presented the highest and lowest total operating costs (TOC), respectively. However, when TOC was evaluated per kg of the weaned calf, the highest and lowest costs were associated with the ONM (US$ 2.81 ± 0.03/kg) and 2TAI/24 + NM (US$ 2.17 ± 0,04/kg) scenarios, respectively. Our model suggests that reproductive strategies that use TAI have a better economic performance than those under NM. However, when performing three TAI with an interval of 40 days, the benefit was lower; in some cases, it was even worse than the ONM. Combining TAI with early pregnancy diagnosis resulted in better economic performance than other TAI programs and NM. The 2TAI/24 + NM scenario outperformed the others due to the contrast between its high income and moderate costs. Beef cattle production is a highly complex system. Simulations models, specifically ABS models, could make the decision-making process on complex systems straightforward and effective. Furthermore, ABS models can overcome the limitations of conventional research approaches, such as high costs and long experimentation periods.

An agent-based simulation model to compare different reproductive strategies in cow-calf operations: Technical performance.

The objective of this study was to create a stochastic, agent-based simulation model of a synthetic population of beef cattle, and then use it to compare the technical performance of different reproductive strategies. The model was parameterized using data from a real beef cattle herd and from the peer-reviewed scientific literature to represent a Nelore cattle herd in the state of São Paulo, Brazil. Ten scenarios were evaluated: natural mating (NM) only (ONM); one timed artificial insemination (TAI) plus NM (1TAI + NM); two TAI plus NM, with 24, 32, and 40 days between inseminations (2TAI/24 + NM, 2TAI/32 + NM, and 2TAI/40 + NM, respectively); three TAI without NM, with 24, 32, and 40 days between TAI (3TAI/24, 3TAI/32, and 3TAI/40, respectively); and three TAI plus NM, with 24 and 32 days (3TAI/24 + NM and 3TAI/32 + NM, respectively). NM began 10 days after the last TAI and was performed until the end of the breeding season. The size of the female herd was set to contain up to 400 individuals. The bull population was established at 0, 7, or 15 bulls depending on the used scenario. Simulation was performed for 5000 days. The outcomes for each scenario are means ± S.E. assessed on 32 farms at 1-day time intervals and on an animal-by-animal basis after steady state was reached (1825 days). The 3TAI/24 + NM scenario resulted in a greater number of births (279.85 ± 0.47 births), while the ONM scenario had the least value (202.38 ± 0.43 births). The heaviest males and females at weaning belonged to 3TAI/24, with 190.85 ± 0.17 kg for males and 173.89 ± 0.13 kg for females. The ONM scenario had the lightest males (166.84 ± 0.18 kg) and females (151.75 ± 0.16 kg). The greatest and least total pregnancy rates were found in 3TAI/24 + NM (0.91 ± 0.00) and ONM (0.62 ± 0.00), respectively. The ONM scenario required 52.5 days more than scenarios that included TAI to reach 50% of pregnancy. The greatest ages at culling for cows was 3TAI/24 + NM (3658.88 ± 10.41 days). In contrast, the lowest age at culling was found in ONM (2823.93 ± 8.28 days). We concluded that the proposed model represents the main interactions of a real beef cattle herd. It has all the advantages of a physical experiment, but does not require incurring significant expenses nor altering the real system. This study offers evidence that the scenarios that present the best technical performance are those that used TAI with a 24-day interval between inseminations.

Herd-level associations between somatic cell counts and economic performance indicators in Brazilian dairy herds.

The aims of the present study were to provide a portrait of the techno-economic status of dairy herds in Minas Gerais, Brazil, particularly with respect to bulk-tank somatic cell count (BTSCC) data, and to examine the herd-level associations of BTSCC with various economic performance indicators (EPI). Data from 543 herds, 1,052 herd-year records in total, spread over 3 years (2015-2017), from the South and Southwest mesoregions of Minas Gerais State were provided by the Brazilian Support Agency to Micro and Small Companies Division Minas Gerais (SEBRAE). Herds had an average of 82 lactating cows per herd, milk yield of 17 L/cow per day, and availability of financial information via routine monthly economic surveys. The EPI data (revenue, gross margin, GM; net margin, NM; profit; break-even point; and operational profitability) of each herd was measured monthly by SEBRAE personnel, and herd-year averages of all variables were computed. Bulk-tank data (SCC, total bacterial count, content of crude protein and fat) taken by producers or dairy processors were recorded by SEBRAE personal; and corresponding herd-year averages were calculated and included in the SEBRAE database. There were 209 selected herds, which passed all edit checks, and which had data for all 3 years. The EPI (all expressed on a per-cow basis, $/cow per year) were analyzed, including the effects of region, year, log (ln) BTSCC, production level, and herd size, together with the random effect of herd nested within region. A high proportion of herds (94.6%) presented data records (herd-years) with an average BTSCC > 200 × 103 cells/mL: 37.8% of herd-year records had BTSCC between >200 and ≤400, 14.5% with BTSCC between >400 and ≤500, 25% with BTSCC between >500 and ≤750, and 17.3% with BTSCC >750. For each unit increase in ln BTSCC, revenue declined by $228.5/cow per year, GM by $155.6/cow per year, and profit by $138.6/cow per year. Herds with cows of lower production (<14 kg/d) presented lower GM ($286.8/cow per year) compared with herds containing cows producing ≥14 kg/d (≥14 and <19 kg/d = $446.5, and ≥19 kg/d = $601.9). The small-scale milk producers (<39 lactating cows) presented lower revenue ($1,914.9/cow per year) and GM ($274.5/cow per year) and consequently a negative profit (-$224.1/cow per year) compared with other herd size categories (≥39 lactating cows). The reduction in milk yield was 641 L/cow per lactation for each unit increase in ln BTSCC; this represented 9.4% of the milk yield per lactation, assuming an average milk production of 6,843.3 L/cow per lactation of cows from herds that had BTSCC ≤ 200 × 103 cells/mL. Consequently, we found a negative association of BTSCC with profit; profit declining from $227.0 to -53.1/cow per year when the BTSCC increased from 100 to 750 × 103 cell/mL. In short, the lower the BTSCC, the greater the revenue, GM and NM, profit, and operational profitability of the herds. The reduction of milk yield was the main factor associated with higher BTSCC.

Comparative costs of the Mouse Inoculation Test (MIT) and Virus Isolation in Cell Culture (VICC) for use in rabies diagnosis in Brazil.

The decision to use laboratory animals rather than in vitro methods is frequently based on the financial costs involved, so the objective of our study was to compare the costs of performing the Mouse Inoculation Test (MIT) and Virus Isolation in Cell Culture (VICC) for use in rabies diagnosis in Brazil. Based on observations of laboratory routines at the Pasteur Institute, São Paulo, we listed the fixed cost (FC) and variable cost (VC) items necessary to perform both tests. Considering that 200 MITs are equivalent to 350 VICC assays, in terms of facilities and staff-hours needed per month, we calculated, for both tests, the average total cost per sample, the costs of the implementation of the laboratory structure, and the costs of routine use. With regard to absolute values, the total cost was mainly influenced by FC items, as they represented 60% of the cost for the MIT and 86% of the cost for VICC. A sample analysed by the MIT costs around 205% more than one analysed by using VICC. The MIT costs 74% and 406% more than VICC, when implementation costs and routine use per month, respectively, are taken into account. Our results can assist in the resolution of costing disputes that could hinder the replacement of animals for rabies diagnosis in Brazil. The method demonstrated here might also be useful for cost comparisons in other situations where animal use still continues when validated alternatives exist.

Food safety systems in a small dairy factory: implementation, major challenges, and assessment of systems' performances.

The present study describes the implementation of a food safety system in a dairy processing plant located in the State of São Paulo, Brazil, and the challenges found during the process. In addition, microbiological indicators have been used to assess system's implementation performance. The steps involved in the implementation of a food safety system included a diagnosis of the prerequisites, implementation of the good manufacturing practices (GMPs), sanitation standard operating procedures (SSOPs), training of the food handlers, and hazard analysis and critical control point (HACCP). In the initial diagnosis, conformity with 70.7% (n=106) of the items analyzed was observed. A total of 12 critical control points (CCPs) were identified: (1) reception of the raw milk, (2) storage of the raw milk, (3 and 4) reception of the ingredients and packaging, (5) milk pasteurization, (6 and 7) fermentation and cooling, (8) addition of ingredients, (9) filling, (10) storage of the finished product, (11) dispatching of the product, and (12) sanitization of the equipment. After implementation of the food safety system, a significant reduction in the yeast and mold count was observed (p<0.05). The main difficulties encountered for the implementation of food safety system were related to the implementation of actions established in the flow chart and to the need for constant training/adherence of the workers to the system. Despite this, the implementation of the food safety system was shown to be challenging, but feasible to be reached by small-scale food industries.

Contribution to economic evaluation of systems that value animal welfare at farm / Contribución para la evaluación económica de sistemas que procuran el bienestar / Contribuição para a avaliação econômica de sistemas que prezam pelo Bem-Estar dos animais de produção

The demand for “welfare friendly” products increases as public conscience and perception on livestock production systems grow. The public and policy-makers demand scientific information for education and to guide decision processes. This paper describes some of the last decade contributions made by scientists on the technical, economical and market areas of farm animal welfare. Articles on animal welfare were compiled on the following themes: 1) consumer behavior, 2) technical and economical viability, 3) public regulation, and 4) private certification policies. Most studies on the economic evaluation of systems that promote animal welfare involved species destined to produce export items, such as eggs, beef and pork. Few studies were found on broilers, dairy cows and fish, and data regarding other species, such as horses, sheep and goats were not found. Scientists understand that farm animal welfare is not only a matter of ethics, but also an essential tool to gain and maintain markets. However, it is unfortunate that little attention is paid to species that are not economically important for exports. Studies that emphasize on more humane ways to raise animals and that provide economic incentives to the producer are needed. An integrated multidisciplinary approach is necessary to highlight the benefits of introducing animal welfare techniques to existing production systems.

La demanda por productos diferenciados en términos de bienestar animal, crece a medida que aumenta la información, conciencia y percepción del público con relación a la producción animal. La sociedad, los encargados de la legislación y los científicos del área, buscan información para la construcción de opinión y la toma de decisiones. Por esto, los investigadores deben usar su capacidad técnica, de investigación y analítica para evaluar los efectos de la producción pecuaria en el bienestar animal y humano. El objetivo de esta revisión, fue analizar las contribuciones de los científicos sobre las implicaciones técnicas, económicas y mercadotécnicas de las mejoras del bienestar animal, para dejar disponible un análisis más preciso de lo que se ha realizado académicamente sobre el tema en la última década. Se compilaron artículos sobre bienestar animal aplicados a la producción animal, en los siguientes temas: 1) comportamiento del consumidor, 2) viabilidad técnica y económica, 3) regulación pública y 4) políticas privadas de certificación. Se encontró que los estudios de evaluación económica en sistemas que procuran el bienestar animal, se concentraron en criaderos destinados a productos de exportación, como huevos, carne bovina y suina. Pocos trabajos se han desarrollado sobre aves de carne, bovinos lecheros y peces. No se encontraron datos sobre otras especies diferentes a las antes mencionadas. Los científicos perciben que el bienestar animal, además de ser una cuestión ética, es esencial para conquistar y mantener mercados. Sin embargo, es preocupante que este tipo de investigaciones se realicen en menor medida en especies poco representativas en las exportaciones. Trabajos sobre bienestar animal, son esenciales para viabilizar técnicas de producción menos agresivas con los animales y para agregar valor a sus productos, incluso a aquellos destinados al consumo interno. Son necesarias más investigaciones en todos los abordajes propuestos, adicionando conocimientos multidisciplinarios para diferentes áreas de estudio.

A procura por produtos diferenciados em relação ao bem-estar animal cresce à medida que aumentam as informações, a consciência e a percepção do público em relação à produção animal. A sociedade e os envolvidos na legislação buscam informação para a construção de opinião e toma de decisões junto aos cientistas da área. Por isso os pesquisadores devem, da maneira mais objetiva possível, usar sua capacidade técnica, investigativa e analítica para avaliar os diversos efeitos da pecuária no bem-estar animal e humano. O Objetivo desta pesquisa foi analisar as contribuições de cientistas sobre as implicações técnicas, econômicas e mercadológicas das melhorias do bem-estar animal, de forma a disponibilizar um análise do que vem sendo feito no setor acadêmico sobre o tema. Foram estudadas publicações da última década (2001-2011), onde se compilaram artigos com enfoque no bem-estar aplicado à produção animal, sob as abordagens: 1) comportamento do consumidor; 2) viabilidade técnica e econômica; 3) regulamentação pública; e 4) políticas privadas de certificação. Constatou-se que estudos de avaliação econômica em sistemas que prezam pelo bem-estar animal se concentraram em criações destinadas a produzir bens de exportação, como ovos e carnes bovina e suína. Aves de corte, bois leiteiros e peixes foram objeto de poucos trabalhos. Não foram encontrados dados sobre outras espécies. Os cientistas percebem que o bem-estar animal, além de uma questão ética, é essencial na conquista e manutenção dos mercados. No entanto, é muito preocupante que estas pesquisas sejam nitidamente menos intensas para espécies pouco representativas para as exportações. Trabalhos na área do bem-estar animal são essenciais para viabilizar técnicas de criação menos agressivas aos animais e para agregar valor aos produtos, mesmo destinados ao mercado interno, e se devem ampliar a outras espécies. Mais pesquisas são necessárias em todas as abordagens propostas, acrescentando conhecimentos de forma multidisciplinar para várias áreas de estudos.