Analyzing White-rumped Vulture breeding behavior using Markovian modeling

Understanding wildlife behavior, including accurate identification, processing, and interpretation of activities or cues, is important to behavioral biology and corresponding conservation strategies. We characterized the breeding activities of the critically endangered White-rumped Vulture Gyps bengalensis following a sequential pattern from courtship to fledging. We recorded 4,160 visual observations of 20 behaviors of eight pairs of White-rumped Vultures from September 2021­April 2022 and constructed Markov chain models to model three composite behaviors (i.e., breeding, foraging, and roosting). We found that vultures at four nests displayed >70% of the time in breeding behavior, and each nest produced offspring, indicating a potential correlation between breeding behavior and successful reproductive outcomes. Our model explained each composite behavior with high accuracy. Identifying behaviors White-rumped Vulture have practical applications for developing management plans for their conservation, including the timing of critical reproductive events. Our findings and approach can improve our understanding of White-rumped Vulture behavioral ecology and conservation and have applications for other species.(AU)

Zoo visitors as a source of enrichment to reduce abnormal behavior in captive rhesus macaques (Macaca mulatta) in the Central Zoo, Kathmandu, Nepal

Overexpression of abnormal behavior among captive primates indicates poor management practices. The type, frequency, and contributing factors of abnormal behaviors vary highly across individual animals in captive settings. This study explored if sex, rearing history, the number of visitors, and type of visitor-monkey interactions affected the behaviors of captive rhesus macaques (Macaca mulatta) housed at the Central Zoo in Kathmandu, Nepal. Behavioral observations of six adult rhesus macaques (ages 4­12 years; two were rescued from the wild, and four were born in the zoo) were conducted using the focal animal sampling method. Observations were collected daily in two conditions (7:00­10:00 AM, without visitors present; and 10:00 AM­1:00 PM, with visitors present). During the visitor presence condition, instantaneous scan sampling also was implemented every 10 minutes to record the number of visitors and the type of visitor-monkey interaction. Resting, feeding and grooming were the most prevalent activities, and abnormal behavior ranked fifth throughout the observation period. Significant differences were observed in abnormal or stress-related behavior by sex and rearing history: females engaged in abnormal behavior more than the males, and rescued monkeys engaged in more abnormal behavior than the captive born. Abnormal behavior decreased, begging behavior increased as the number of zoo visitors and the extent of visitor-monkey interaction increased. We conclude that captive rhesus macaques respond to zoo visitors as a source of enrichment, and visitors' presence helps decrease abnormal or stress-related behavior levels.

Sex and animal behavior on yield and bruises in different beef cuts / Sexo e comportamento animal no rendimento e contusões em diferentes cortes de carcaça de bovinos

The objective of this study was to examine the effects of behavioral differences in cattle on bruising on different cuts and on carcass yield. A total of 4,061 lots of cattle were evaluated, which corresponded to 199,026 carcasses. Animal temperament was classified as calm, anxious, or excited. The following carcass cuts were evaluated: round, rump, shin, thin flank, tenderloin, and rib. Of the total number of slaughtered animals, 68.26% had at least one type of bruise with complete removal of the affected tissue. There was an interaction effect between sex and temperament on the occurrence of bruises on the different cuts and on carcass yield. In castrated males, bruises on the round, rump, shin, and tenderloin cuts did not differ between temperament classes, but the excited males showed more bruises on the thin flank and rib cuts. Among the females, for all cuts, the number of bruises was higher (P<0.05) in those with excited temperament than in the anxious and calm animals, which did not differ (P>0.05). Additionally, carcass yield relative to plant weight decreased (P<0.05), with the calm females exhibiting the highest values, followed by those with anxious and excited temperament. In the castrated males, however, although performance declined, those with anxious and excited temperament did not differ (P>0.05). Females and more reactive animals have more bruises on their carcass.(AU)

O objetivo desta pesquisa foi avaliar os efeitos das diferenças comportamentais dos bovinos e seus reflexos nas contusões nos diferentes cortes e nos valores de rendimento de carcaça. Foram avaliados 4.061 lotes de bovinos, perfazendo 199.026 mil carcaças. O temperamento animal foi classificado em calmo, ansioso e excitado. Foram avaliados os cortes das carcaças divididas em coxa, alcatra, dianteiro e lombo, vazio e costela. Do total de lotes de animais abatidos, 68,26% apresentaram pelo menos um tipo de contusão com remoção completa do tecido afetado. Ocorreu interação entre o sexo e temperamento animal para os diferentes cortes na ocorrência de contusões e no rendimento de carcaça. Nos machos castrados as contusões dos cortes da coxa, alcatra, dianteiro e lombo não diferiram entre as classes de temperamento, tendo os animais agressivos mais contusões nos cortes do vazio e costela. Nas fêmeas em todos os cortes, as quantidades de contusões verificadas foram superiores (P<0,05) para animais com comportamento excitado do que animais ansiosos e calmos, não ocorrendo diferença entre os mesmos (P>0,05). O rendimento de carcaça em relação do peso de frigorífico quanto as classes comportamentais, nas fêmeas foi decrescente (P<0,05) com maiores valores para animais calmos, seguidos dos animais ansiosos e com menores rendimentos para animais com temperamento excitado, enquanto nos machos castrados, embora o rendimento tenha sido decrescente, animais com temperamento ansioso e excitado não diferiram (P>0,05). Carcaças oriundas de fêmeas e de animais com maior reatividade apresentam mais lesões.(AU)

Behavioral fractal method associated with GPS tracking to spatial activity sequences of grazing cattle

Global positioning and geographic information systems are essential for studying foraging animal behavior. This study aims to implement a fractal self-similarity and chaos game computational efficient methodology to determine the behavior-associated fractal using GPS data of activity sequences in spatial ranges of livestock movement trajectories in interaction with habitat factors. Six cows were randomly selected with an average weight of 480 kg, maintained under the same conditions, and a GPS-equipped collar was installed, programmed at intervals of 1 min and an average of 9 h daylight. Roughly 192810 registries and an average of 32135 signals per cow from trajectory tracking in spatial activity sequencing were used as a variable of interest in the fractal characterization methodology. Spatial patterns were evaluated using the Morán's spatial autocorrelation indices, cluster, and non-parametric statistics, evaluating deterministic spatial patterns of preferential activities associated to spatial ranges of less than 7.1 m (resting 42 %, grazing 38 %). GPS information was refined through spatial ranges and changes in activities under resting, eating, traveling, and complementary schemes associated to the fractal displacement behavior of grazing cattle. This information was processed and mapped using fractal self-similarity rules in the Sierpinski triangle to determine the typical fractal of spatial activities per animal in the habitat. The particular fractal record of each bovine as a function of trajectory sequences was mapped for binary image matrices, registering a good classification (83 %) of the animals by breed and climatological cycle, using information from the sequencing of spatial activities associated to the preferred behavior in the habitat.

Effect of the performance, calving date and lactation period on the probability of pregnancy in beef cows

Determining what and how much each environmental factor affects pregnancy is crucial to the sustainability and management of beef cow herds. The study evaluated through logistic regression the effect of environmental variables on the increase or reduction in the pregnancy rate of beef cows. The average pregnancy rate in the cows was 73 %, with an average age for the herd of 3.7 years. An increase in age of one year represented a 30 % increase in pregnancy, while a reduction of one year reduced the odds of pregnancy in the cows by 23 %. During the lactation period, an extra seven days' lactation reduced the odds of pregnancy by 12 %. For every seven days that weaning was brought forward, the cows' pregnancy odds increased by 14 %. An increase of 0.1 kg in average daily gain represented an increase of 17 % and 15 % in the odds of pregnancy during the first 60 days post-partum and 60 days to the end of the reproductive period. On the other hand, the loss of 0.1 kg in average daily gain resulted in a 14 % and 13 % reduction in the cows' pregnancy odds, respectively. Factors such as age, the precocity of calving in the calving season, the time the calf remains with the cow and better performance in cows between calving and the end of the mating are strategies that increase the chances of pregnancy in beef cows.(AU)

Maternal instinct of imported meat direction cattle and ethology of their calves

The examination of maternal qualities in the ethology of cows and their young offspring, derived from the study on adaptability and productivity of second and third-generation Aberdeen Angus cattle imported to Kazakhstan from Canadian and European selection, is presented in this paper. The findings indicate that Canadian heifers, belonging to the second generation, displayed extended feeding behavior throughout the day, dedicating 33.2 minutes or 2.2% more time to feeding compared to their European counterparts (P < 0.001). Similar disparities between groups were observed in the duration of the ruminant process. Moreover, Canadian heifers consumed water for an additional 2 minutes or 0.6%, which can be attributed to their higher daily feed intake. The calving process of Aberdeen Angus cows generally proceeded smoothly, demonstrating a well-developed maternal instinct towards their offspring. Notably, calves born from Canadian cows exhibited greater agility and achieved the ability to stand on their feet in a shorter time, with an average duration of 41.0 ± 1.60 minutes, which was 11.7% faster than European calves. Additionally, Canadian calves displayed a shorter time to locate their mother's breast, with an average duration of 68.0 ± 7.70 minutes.(AU)

Automatic cattle weighing on pastures with behavioral analysis during drinking

t Livestock body weight (BW) and average daily weight gain (ADG) are primary indicators of beef cattle productivity. The conventional method of weighing involves moving the cattle to a weighing location, which is labor-intensive, stressful for the animals and has a negative impact on their growth. An alternative approach is to use special weighing platforms attached to the drinkers to weigh the animals. This method enables daily monitoring of BW and ADG without incurring additional labor costs or stress. In this study, an experimental weighing platform, previously developed at KazATU and named after S. Seifullin, was employed to measure livestock's partial body weight (PBW). The weighing platform recorded the weights of the animals on the front legs at one-second intervals, allowing for subsequent calculation of the animals' total weight. However, due to significant weight fluctuations observed when the animals were on the platform, the accuracy of calculating the weight based on a simple average of the one-second measurements was questionable. Hence, an algorithm was developed to determine live weight by analyzing the primary data from the scales and identifying moments of animal immobility during drinking. The calculated results were compared with both mean and median values and data from Kazakhstan's information base of selection and breeding work (IBSBW). The experimental method exhibited a stronger correlation (r = 0.925) with the actual IBSBW data compared to the mean method (r = 0.887) or the median method (r = 0.921).(AU)

Reprodução de procionídeos / Procyonids reproduction

Poucas informações a respeito da biologia dos procionídeos estão disponíveis para quem busca conhecer mais sobre essas espécies. Entretanto, alguns estudos a respeito da reprodução destes animais foram realizados. As principais espécies encontradas no Brasil são o quati, o guaxinim e o jupará, e, dentre esses, o quati se destaca por ser o que possui o maior número de informações reprodutivas. A maioria dos procionídeos aparece como espécies não ameaçadas, porém a falta de informações sobre estes animais pode fazer com que estes dados possam estar defasados. É importante o conhecimento reprodutivo dos procionídeos pois, devido as ações antrópicas que ocasionam a perda de habitat natural, essas espécies, em breve, podem entrar para a lista de animais ameaçados de extinção. Assim, esse artigo tem como objetivo descrever alguns dados por meios de estudos reprodutivos que podem auxiliar ao desenvolvimento de estratégias de conservação dessas espécies.(AU)

Little information about the biology of procyonids is available for those who want to know more about these species. However, some studies regarding the reproduction of these animals were developed. The main species found in Brazil are coati, raccoon, and kinkajou, among which the coati stands out for being the one with the highest number of reproductive information. Most procyonids appear as non-threatened species, but the lack of information about these animals may cause these data to be outdated. Reproductive knowledge of procyonids is important because, due to anthropic actions that cause loss of natural habitat, these species may soon enter on the list of endangered animals. Thus, this article aims to describe some data by means of reproductive studies that can help to develop conservation strategies for these species.(AU)

Breeding behavioral activities of captive red pandas in Nepal

The red panda (Ailurus fulgens) population is decreasing, with less than 10,000 individuals in the wild because of habitat destruction, fragmentation, and illegal hunting. Captive breeding has become an increasingly crucial strategy for conserving endangered species, but efforts to generate self-sustaining populations have failed despite ample resources being allocated. Animals are often stressed in captivity, and it is necessary to examine reproductive behavior relating to the complexity of habitat requirements, dietary preferences, and, in particular, pregnant mothers and their sensitivity to disruptions. Using videography, we observed the reproductive behavior of two red pandas along with other behavioral activities in the Central Zoo, Kathmandu, Nepal. We collected behavioral data from December 2020 to June 2021 using scan and focal sampling. Reproductive behaviors (e.g., scent-marking, allogrooming, chasing, running, aggressiveness, mating, and feeding feces) were observed, along with behaviors like locomotion, climbing, standing, self-grooming, feeding, sleeping, self-play, and stretching. We observed 1­2% of reproductive behavior from total activity. Copulation was attempted on three occasions suggesting reproduction can be successful if animal husbandry is properly managed. We recommend zoo managers further refine strategies for captive breeding endangered species such as red pandas. Successful captive breeding benefits the zoo, and captive-born animals can mitigate extinction in the wild.

Stingless bee Trigona spinipes (Hymenoptera: Apidae) behavior on chayote flowers (Sechium edule)

This experiment aimed to evaluate the forage species and their effect on fruit production of the chayote crop. For this, the culture was under observation in the first ten minutes at each time, from 7:00 am to 6:00 pm, with three repetitions, in each year studied (1994, 2001, 2009 and 2016). With the exception of 2009, Trigona spinipes stingless bees were frequent and constant insects in these flowers between 8:00 am and 1:00 pm, visiting mainly male flowers for nectar collection and due to foraging behavior this stingless bee may be considered a pollinator of the chayote.(AU)

Influence of color and brightness on ontogenetic shelter preference by the prawn Macrobrachium rosenbergii (Decapoda: Palaemonidae)

The giant river prawn, Macrobrachium rosenbergii (de Man, 1879), is a species of great commercial importance. It is farmed under different conditions that translate to a great range of light environments, which impact their behavior and productivity. We present the first study employing both visual modeling and beha vioral data to evaluate the ontogenetic changes in color preferences of juveniles and adults of M. rosenbergii. We offered ten shelters of different colors to juveniles and adults and registered their preferences. Our results show that shelter preference changed with ontogeny: juveniles chose shelters based on chromaticity (preference for blue), while adults based their decisions on brightness (preference for dark grey). This preference adults show for dark colors is probably associated with light avoidance behavior. We recommend providing blue shelters for juveniles and dark shelters for adults.(AU)

Effect of solar radiation on Holstein heifers' physiological variables and grazing behavior

The objective was to assess the physiological and behavioral variables of pasture-raised Holstein heifers on the basis of their coat color. Eight heifers were used, four with black coat, and four with white coat. In the morning and afternoon periods, their physiological variables were measured, namely respiratory rate (RR, mov min. -1), rectal temperature (TR, ºC), and coat surface temperature (TS, ºC). The behavior analysis considered the site (sun or shade), position (standing or lying down), and activities (idleness, rumination, grazing, and others). The data of the physiological variables were assessed through analysis of variance, and significance, through Tukey's test at 5%, while behavioral data were assessed using the Chi-squared test (SAS Software). There was a difference for all of the heifers' physiological variables as a function of coat color (p < 0.0001) and period (p < 0.0001), with black ones showing greater results than white ones as to all physiological variables in the afternoon period (p < 0.0001). Grazing behavior is reduced during the hottest hours of the day. We conclude that solar radiation changes the physiological variables and grazing behavior of pasture-raised Holstein heifers.(AU)

Principais aspectos sanitários na produção de peixes ornamentais / Main sanitary aspects in production of ornamental fish

Sabe-se que, para lidar com peixes, é necessário se atentar não apenas aos aspectos nutricionais e genéticos, mas sobretudo às questões ambientais, como controle da qualidade de água, e sanitários, como cuidados relacionados aos agentes externos e patogênicos. Qualquer desequilíbrio dentro de todas essas variáveis pode levar ao aparecimento de enfermidades. Dessa forma, como proceder para 6. Principais aspectos sanitários na produção de peixes ornamentais pixabay.com evitar a instalação de doenças em uma produção de peixes ornamentais? A resposta é a prevenção. Infelizmente, na maioria dos casos, a prevenção só vai ser buscada pelos produtores após a instalação de algum problema sanitário na propriedade. Portanto, cabe ao profissional especialista contratado não apenas solucionar o problema, mas também identificar pontos críticos que possam minimizar ou inviabilizar uma nova ocorrência do problema na propriedade.(AU)

Milk supplementation: effect on piglets performance, feeding behavior and sows physiological condition during the lactation period

The present study aimed to investigate the effect of milk liquid and powder supplements on piglets' performance, drinking behavior, and sow back-fat thickness change during the lactation period. There were four experimental groups (n = 24), and in the control group (n = 6), the piglets were suckled from the sow. For the supplemental groups (n = 18), milk powder (MP), milk liquid by feeding trough (MLFT), and milk liquid feeding by the bucket (MLFB). Data were collected with the weight of a total of 252 piglets measured at birth, at 14 days and at weaning (28 days), respectively. Sow back-fat thickness was measured 3 days before farrowing, 14 days after farrowing and at weaning. There were significant differences in average daily weight gain between day 14 and weaning age for the MP and MLFT (P < 0.05) but not in MLFB (P > 0.05). For approaches to the feeder, there were significantly higher in MP and MLFT groups (P < 0.05). Based on the examination of sow back-fat thickness, the back-fat loss was minimal (P < 0.05) in the MP and MLFT compared to the MLFB and the control. Giving the milk supplement as powder and liquid by feeding trough has increased the piglets' average daily gain and body weight on day 14th and the weaning day. Moreover, the back-fat thickness reduction of sows in the supplemental groups is lower compared to the control group.

Group-training of rams at puberty for artificial vagina-mediated semen collection and its influence on semen quality and sexual behavior

There is a paucity of information with respect to group-training for artificial vagina and its influence on semen characteristics and sexual behavior of young untrained rams. A total of 18 healthy Najdi rams (with an initial body weight of 40-45 Kg and 7-8 month-old) were consequently used herein to test the usefulness of group-training for artificial vagina-mediated semen collection during the breeding season. Rams were randomly segregated into three groups (n = 6 rams per protocol), and the whole experiment was lasted for 10 weeks. The 1st group was subjected to a training protocol where one untrained ram was placed for 20 min with a teaser ewe, while the 2nd group were subjected to a protocol where one untrained ram was placed for 20 min with one trained ram and a teaser ewe, whereas the 3rd group were subjected to a protocol where three untrained rams were placed for 20 min with one trained ram and a teaser ewe. The obtained results clearly (P < 0.05) showed that training young rams in group has increased their sperm concentration and sexual stimulation, shortened the period of their training time, and descriptively had a complete training efficiency. The sexual stimulation of young untrained rams was intensified by the competition between rams in the co-presence of a trained ram. Collectively, these data may suggest that group-training of rams at puberty is a better protocol for AV-mediated semen collection compared to individual training. Some shortcomings were noted herein, but research dealing with this subject may very well improve the reproductive performance of young untrained rams.(AU)

The impact of training on stockpersons' behaviour and cows' fear response

In tropical developing regions, such as Brazil, animal welfare (AW) has been gaining increasing attention, while stockperson job satisfaction, which is intimately related to AW, is often neglected. This research evaluated the effects of AW training on stockpersons' attitudes and behaviour towards dairy cows and the impact on cows' fear of humans. Ten dairy farms with pasture-based systems where animal handlers are farm owners or employees were selected from three regions of Sao Paulo, Brazil. The experiment consisted of four stages: 1) Selection of pasture-based dairy farms; 2) First assessment of attitudes, human behaviour, and cows' flight distance (day one ­ D1); 3) Pre-assessment of owners' and employees' AW knowledge, and training (day two ­ D2); and 4) Final assessment of attitudes, human behaviour, cows' flight distance, and owners' and employees' AW knowledge (day three ­ D3), focusing on the training's effects on human attitudes and behaviour, and cows' fear of humans. Among owners and employees, positive attitudes were more often expressed, and negative attitudes were less frequent on day three (D3) after training. Nevertheless, the expression of positive attitudes by farm owners was less common compared to employees. Stockpersons manifested positive behaviour more frequently at D3 than on day one (D1), before training, in contrast to negative behaviour at D1. Taking all cow handling observations together, including those before and after training, the greatest percentage of negative behaviour was at the time of moving the cows from the holding area to the milking stalls (18% of all observed human behaviour), followed by moving cows out of the milking parlour (17%), positioning cows for milking (15%) and placing/removing the milking suction devices (1%). Positive human behaviour usually occurred when moving cows from the holding area to the milking stalls (21%) and during the positioning of cows for milking (19%). After training, cows' flight distances decreased. In conclusion, the training may have promoted positive human behaviour and reduced the number of fearful cows. Therefore, AW training may positively influence human behaviour, technical expertise, the reduction of fear in cows, and stockpersons' attitudes.(AU)

Characterization of intronic SNP located in candidate genes influencing cattle temperament

The objective of this study was to evaluate the effect of intronic single nucleotide polymorphisms (SNP) on temperament traits in a Brahman cattle population. The SNP located in CACNG4, EXOC4, NRXN3, and SLC9A4 candidate genes were genotyped in 250 animals with temperament records of exit velocity, pen score, and temperament score. Rs3423464051:G>A in the CACNG4 gene was associated with exit velocity and temperament score. An in silico analysis of the five intronic SNP showed that alternative alleles of CACNG4-rs3423464051, EXOC4-rs109393235, and SLC9A4-rs109722627 SNP could alter branch point sites during splicing, while a protein-protein interaction network analysis demonstrated a GRIA2 gene-mediated interaction between CACNG4 and NRXN3. The present results support previously reported evidence regarding bovine temperament-related candidate genes, particularly CACNG4, which is a confirmed candidate gene in need of more detailed analyses to reveal its role in temperament-related traits.(AU)

Exame clínico andrológico em búfalos: particularidades e mercado / Clinical andrological examination in buffaloes: particularities and market

A bubalinocultura tem expandido mundialmente com grande importância socioeconômica na produção de leite, carne e na tração animal. No entanto, algumas características como: a sazonalidade, poucos reprodutores com genética superior para ser multiplicada e reduzido número de touros com sucesso de coleta constante de sêmen nas Centrais, dificultam a obtenção de maiores índices reprodutivos a nível de Brasil. Neste contexto, a eficiência reprodutiva do rebanho possui papel de destaque, consequentemente, o touro bubalino e a realização do exame andrológico são essenciais para o desenvolvimento da bubalinocultura. Apesar da realização de pesquisas ao longo dos anos relacionadas à andrologia em búfalos, na prática a campo ainda existe uma lacuna referente aos aspectos reprodutivos nessa espécie, fazendo com que haja uma demanda por conhecimento específico. Diante disso, objetivou-se abordar alguns dos principais aspectos da andrologia na espécie bubalina, para auxiliar o Médico Veterinário no atendimento clínico e andrológico visando alcançar uma boa eficiência reprodutiva.(AU)

Buffalo farming has expanded worldwide with great socioeconomic importance in the production of milk, meat and animal traction. However, some characteristics such as: seasonality, few sires with superior genetics to be multiplied and reduced number of bulls with constant semen collection success in the Centrals, make it difficult to obtain higher reproductive rates in Brazil. In this context, the reproductive efficiency of the herd plays a prominent role, consequently, the buffalo bull and the performance of the andrological examination are essential for the development of buffalo breeding. Despite conducting research over the years related to andrology in buffaloes, in field practice there is still a gap regarding reproductive aspects in this species, causing a demand for specific knowledge. In view of this, the objective was to address some of the main aspects of andrology in the buffalo species, to assist the veterinarian in clinical and andrological care in order to achieve good reproductive efficiency.(AU)

Behavior and swimming performance of local fish in the ecosystem waters of rivers, oxbow and peat swamps

The four fish species, Trichogaster pectoralis, Barbodes schwanenfeldii, Osphronemus gouramy, and Wallago leeri have the same body size, representing different habitats. Therefore, this study aimed to determine the four species swimming abilities and speeds, including sustained, maximum sustained, prolonged swimming speed, and burst speed. The four species were brought using oxygenated plastic bags to the Aquatic Resources Utilization Laboratory at Riau University. Then it was acclimated in an aquarium measuring 100×50×50 cm with an aeration and filtering system to maintain water quality. The four groups of species were forced to swim in the swimming channel of the flume tank, with different current speeds for each individual tested. The swimming activity of the fish was recorded using a high-speed video camera (Casio HS Exlim, EX-ZR400, Casio Computer Co. LTD, Japan). The results showed that the swimming speed of B. schwanenfeldii was higher than O. gouramy, T. pectoralis, and W. leeri. The maximum sustained swimming speed of B. schwanenfeldii is about 5.1 BL/s, and 14.2 BL/s for the burst speed. Meanwhile, the sustained swimming speed of O. gouramy (1.6 BL/s) and the burst speed is 7.2 BL/s. The maximum sustained swimming speed of T. pectoralis was 1.6 BL/s, and the burst speed was 5.7 BL/s. In addition, the maximum sustained swimming speed of W. leeri is only 0.5 BL/s and 2.4 BL/s for the burst speed. The ability of these four fish to swim was influenced by the morphology of the tail fin, body shape, and the habitat where they live.

Performance and behavior of piglets fed diets with different metabolizable energy levels / Desempenho e comportamento de leitões alimentados com dietas com diferentes níveis de energia metabolizável

This study evaluated the effect of different metabolizable energy (ME) levels in diets on digestibility, performance, and feeding behavior of weaned piglets. A digestibility study to determine ME levels was performed using 12 male piglets with 11.5 ± 0.5 kg body weight (BW), in a cross-over design fed with different ME levels (treatments). In the performance study were used 64 female piglets with 7.5 ± 0.8 kg BW, in a randomized block design with four treatments (3.30, 3.40, 3.50, and 3.60 Mcal.kg-1 ME levels), and feeding program with three phases (pre-initial I, pre-initial II, and initial). For feeding behavior, four pens of each treatment were monitored with cameras. The crude-protein digestibility coefficient reduced as dietary ME level increased (P <0.05). In pre-initial I animal performance was not influenced (P <0.05) by ME diet levels, and in the pre-initial II and initial phases, increases in ME caused quadratic (r² 0.99) and linear (r² 0.99) effects on daily feed intake, respectively. When ME levels increased, feed conversion ratio decreased linearly in the pre-initial II phase (r² =0.98), and quadratically in the initial phase (r²= 0.99). The number and duration of feeder visits linearly decreased as the diet energy levels increased (P <0.05). Weaned piglets can regulate feed intake according to dietary ME levels. The performance of weaned piglets can be maintained using diets containing metabolizable energy levels between 3.30 at 3.60 Mcal.ME.kg-1 if the ratio of nutrients to energy is maintained constant.The feed intake behavior of weaned piglets is influenced by increases in dietary metabolizable energy levels evaluated, resulting in fewer and shorter visits to the feeder.

Este estudo avaliou o efeito de diferentes níveis de energia metabolizável (EM) em dietas sobre a digestibilidade, desempenho e comportamento alimentar de leitões desmamados. Um estudo de digestibilidade para determinação dos níveis de EM foi realizado com 12 leitões machos com 11,5 ± 0,5 kg de peso corporal, em delineamento cruzado, alimentados com diferentes níveis de EM (tratamentos). No estudo de desempenho foram utilizadas 64 leitões fêmeas com peso corporal de 7,5 ± 0,8 kg, em delineamento de blocos casualizados com quatro tratamentos (níveis de 3,30, 3,40, 3,50 e 3,60 Mcal.kg-1 ME), e programa de alimentação com três fases (pré- inicial I, pré-inicial II e inicial). Para o comportamento alimentar, quatro baias de cada tratamento foram monitorados com câmeras. O coeficiente de digestibilidade da proteína bruta diminuiu com o aumento do nível de EM da dieta (P <0,05). No pré-inicial I o desempenho dos animais não foi influenciado (P <0,05) pelos níveis da dieta de EM, e nas fases pré-inicial II e inicial, o aumento de EM causou efeitos quadráticos (r² 0,99) e lineares (r² 0,99) na alimentação diária ingestão, respectivamente. Quando os níveis de EM aumentaram, a conversão alimentar diminuiu linearmente na fase pré-inicial II (r² = 0,98), e quadraticamente na fase inicial (r² = 0,99). O número e a duração das visitas aos comedouros diminuíram linearmente à medida que os níveis de energia da dieta aumentaram (P <0,05). Leitões desmamados podem regular o consumo de ração de acordo com os níveis de EM da dieta, o desempenho de leitões desmamados pode ser mantido usando dietas contendo níveis de energia metabolizável entre 3.30 a 3.60 Mcal.EM.kg-1 se a proporção de nutrientes para energia for mantida constante. O comportamento de consumo de ração de leitões desmamados é influenciado pelo aumento nos níveis de energia metabolizável da dieta avaliados, resultando em menos e mais curtas visitas ao comedouro.