The objective of this study was to measure the water disappearance in the drinker and the pattern of daily water intake and estimate the amount of water wasted in pig production. The study will also generate information about the daily behaviour of water intake of pigs in the growing and finishing phases. Sixty male pigs with an average initial weight of 44.43 kg subjected to immunocastration were used. Animals received feed and water ad libitum. The animal-performance data, temperature and humidity, and feed and water intake behaviour were collected in real time during the entire experimental period, while water volume consumed was measured daily. The average water disappearance (WD) was 7.98 L, which increased during the studied period, and 29.07% of this corresponds to the estimated water wasted. The daily WD behaviour revealed an increasing pattern throughout the day for growing and finishing periods, with the registered peak at 16:00 and 15:00 h and intake of 6.24 and 9.48 L, respectively. The time spent drinking (TSD) and number of drinker visits (NDV) also showed a peak in the afternoon: 13:00 and 17:00 h for growing and finishing phases, respectively. The TSD was 282.73 and 268.36 s, and the NDV values were 16.13 and 13.84 for growing and finishing phases, respectively. The results demonstrated an increasing pattern during the animal housing period in WD that is proportional to dry matter intake and body weight, and the water wasted represents a significant portion of WD. The daily pattern of WD, TSD, and NDV increase during the total and growing periods, presenting peak activity at 13:00 h. During the finishing phase, TSD and NDV present a pattern similar to the growing phase, but the peak occurs in the last hour of the day.

The description of growth curves of animals over time is essential for the development of mathematical models to estimate the growth, as well as to determine nutritional requirements and the ideal moment for slaughter (^{Carabús et al., 2017}; ^{Remus et al., 2020}). Growth curves are generated by relating the weights (“Y”) and ages (“t”) of the animals, using nonlinear equations (^{Fernandes et al., 2019}). Equations used to describe animal growth include the Gompertz, logistic, and von Bertalanffy equations (^{Iglesias et al., 2014}). The number of parameters, ease of measurement, and estimation precision are the criteria used to determine the equation to estimate animal growth (^{Kyriazakis & Whittemore, 2006}).

Context: An adequate management of water use is essential in agricultural systems, including pig farming. Reducing the water footprint is important to preserve this natural resource, although there is limited qualitative information about water intake and water intake behaviour, especially in immunocastrated pigs. Aim: The objective of this study was to compare water disappearance, and estimate wasted water and water intake behaviour for immunocastrated and surgically castrated male pigs. Methods: Twenty-four surgically castrated male pigs and 24 entire male pigs submitted to immunocastration were used, with an average initial weight of 29.3 kg (±1.9 kg) and an age of 75 days. The pigs were housed in a growing–finishing facility with 24 pens and two animals per pen; each pen was equipped with a semi-automatic feeder and a bite-ball drinker with a water meter. The disappearance of water was measured by collecting the values of the water meters on a daily basis, and the water intake behaviour was determined by collecting the values of the water meters per hour. Water input and output values were estimated, and wasted water was calculated by subtracting the input from the output value. Key results: The weekly average water disappearance for surgically castrated males was higher (P < 0.05) than that for immunocastrated males, except in the last 2 weeks of the experimental period; the same was observed when expressed based on weight. Castrated animals also wasted 21.4% more water than immunocastrated animals. Regarding the water consumption profile, there were no differences between the two groups; water consumption was higher in the afternoon. The lower water disappearance in immunocastrated pigs was due to the increase in feed intake after the second dose of the immunocastration vaccine and to the lower amounts of waste because of less aggressive behaviour. Conclusion: Immunocastrated male pigs have a smaller water footprint, but a similar water intake behaviour compared with surgically castrated animals. Implications: Knowledge of the profile of water intake and a way to estimate water waste allows more efficient and sustainable management of water resources in pig production systems.

The objective of this study was to evaluate carcass characteristics and meat quality of surgically castrated and immunocastrated male pigs. Data were collected from 24 surgically castrated pigs and 24 immunocastrated male entire originating from the commercial line (Agroceres x Topigs), receiving isonutritive diets and were housed in the same experimental shed, slaughtered at 177 days old, with a slaughter weight of 127.8 (± 6.5) and 135.1 (± 7.8) kg, respectively. Carcass and meat quality characteristics such as carcass yield, lean meat yield, fat content, backfat thickness, muscle depth, pH, meat coloring and, drip, thawing and cooking loss, were evaluated. Immunocastrated pigs have heavier carcass, higher meat yield and lower fat thickness when compared to surgically castrated animals. Regarding meat quality, the immunocastrated presented a lighter meat, less reddness and less water holding capacity. In conclusion, this study confirmed that the carcass of male pigs, submitted immunocastration, has lower yield, however, more meat and less fat content, when compared to carcass of male pigs surgically castrated. Meat quality showed peculiar characteristics for immunocastrated pigs, and can be used more for sausage production, since it retains less water and have smaller redness color compared to surgically castrated pigs.

This study aimed to develop and assess a deterministic mathematical model for predicting the impacts of varying sow replacement rates on the performance of farms producing weaned piglets. Initially, the influence of replacement rate on herd structure was examined using two equations, which accounted for the percentage of sows replaced (55, 45, and 35%), retention rates between parities (13, 9, and 5%), and number of last parities in the herd (6, 7, and 8). The model then estimated sow [...] ABSTRACT This study aimed to develop and assess a deterministic mathematical model for predicting the impacts of varying sow replacement rates on the performance of farms producing weaned piglets. Initially, the influence of replacement rate on herd structure was examined using two equations, which accounted for the percentage of sows replaced (55, 45, and 35%), retention rates between parities (13, 9, and 5%), and number of last parities in the herd (6, 7, and 8). The model then estimated sow