Buffalo Herd Structure and its Repercussions for Condition of Individual African Buffalo Cows

Genotype by environment interactions on culling rates and 305-day milk yield of Holstein cows in 3 US regions

Abstract1. The social behaviour of the African buffalo (Syncerus caffer) was studied between 1981 and 1985 in Lake Manyara National Park, northern Tanzania. Emphasis is placed on the relationships between adult bulls (i.e. older than 7 yrs). 2. These bulls were transient members of the buffalo population of the study area. At any time ± 150 adult bulls were in the area. During the study period 240 individual bulls were recognized, and the number of the 'bull pool' during this period was estimated to be 630. 3. Every few weeks, the bulls switched between the herd state and bachelor state, and wandered from herd to herd, presumably in search of oestrus cows. 4. They did not form stable associations, and when bachelor, they preferentially associated in temporary groups of 3 to 5 bulls. 5. Adult bulls engaged in sparring and showed dominance interactions very rarely. In a dyadic encounter, dominance interactions were only observed between bulls of the same body condition. Encounters involving individuals in different condition resulted in dominance being established without interaction. Fighting is extremely rare and likely to be lethal to both opponents. 6. The switching between both social environments was related to condition loss in the mixed herd and to condition gain in the bachelor state. This resulted in a 'rotating dominance hierarchy'. The bachelor phase is an essential part of the breeding cycle of an adult bull. 7. The necessity of a bachelor phase to recoup body condition may well be a general feature in mammalian species with long breeding seasons.

Bovine viral diarrhoea (BVD) is a worldwide viral cattle disease. Percentage of seropositive animals, especially in the countries with intensive cattle breeding ranges from 60-90%. This infection on our epizootiology area, as well as on area in our surrounding, was for the first time described by OEuriåkoviñ et al. (1966) based on clinical pictures and pathomorphological findings. This was proved by antibody detection by Cvetnić et al. (1968). In the last few years a large number of serology examination was done on the presence of BVDV infection in our area. In 2004 an examination on virus neutralisation antibodies in sera of breeding dairy cattle older than 6 months was carried for the purpose of determining the prevalence of BVDV infection in large and small herds in Southern Bačka and Srem districts. There were 7577 sera samples from small herds, out of which 3457 were from Southern Bačka (26.31% out of total population in all 9 municipalities), and there were 4120 samples from Srem district (25.17% out of total population in all 8 municipalities). The examination included the animals from all settlements (156). From large cattle herds there were 3019 sera samples, out of which 2721 were from 18 large farms in Southern Baåka (38.65% out of total population), and 298 from 4 large farms in Srem district (29.22% out of total population). This examination encompassed animals from 22 large farms on this area. Virus neutralisation test (VN) was carried out according to the standard procedure described in ’’Manual of Diagnostic Tests and Vaccines for Terrestrial Animals’’ Office International des Epizooties (2004) with slight modifications. For test NADL strain of BVD virus and MDBK cell culture were used. The sera were examined in double dilution from 1:2 to 1:512. Virus neutralisation antibodies for NADL strain BVDV were detected in 1833 (24.19%) in the samples from small herds. Out of this number there were 1082 (31.30%) seropositive animals from Southern Baåka and 751 (18.53%) from Srem district. The largest number of seropositive animals in Southern Baåka district were detected in Titel municipality (68.07%) and the lowest in Bački Petrovac municipality (6.63%). In Srem district the largest number of seropositive animals was in Beoåin municipality (34.16%) and the lowest in Irig municipality (7.62%). When comparing all the settlements, the percentage of BVDV seropositive animals ranged from 0% (i.e. settlements with no seropositive animals) up to 86.67% (Krnjeãevci). Virus neutralisation antibodies for BVDV NADL strain were detected in 1667 (55.22%) samples from large cattle herds. Out of this number there were 1500 (55.13%) seropositive animals from Southern Bačka, and 167 (56.04%) seropositive animals from Srem district. The prevalence of seropositive animals in large herds from Southern Baåka district ranged from0%(5 large herds) up to 96.61%. High prevalence (70%) was detected in 7 out of 18 examined herds. The prevalence of seropositive animals originating from large herds in Srem district ranged from 0% (1 large herd) to 96.96%. High prevalence (70%) was detected in 2 out of 4 examined herds. Detected variation in the percentage of seropositive animals in some areas and herds most probably is the result of animal origin and management on the farms, i.e. movement of animals with introduction of new animals into a herd, what also means that the virus enters into a herd and outbreaks of BVDV infection occur. The titre ofVNantibodies in a certain number of animals, especially on certain areas and in some herds ranged up to 1:512 and even more, what was a clear indication of current or recent presence of persistently infected animals in these herds. High percentage of seropositive animals (70%) in 9 large herds most probably is the result of uncontrolled animal movement, entering of BVD virus and frequent outbreaks of BVDV infections in these herds, but this also indicates probable presence of persistently infected animals in the herds. The obtained results point on high prevalence of BVD infection in the examined area. This prevalence is not equal, what point on existence of areas where the infection is not present, or is present only sporadically.

How do free-ranging domestic herbivores reduce competition within owner-determined herds?

A descriptive study of teat morphology, milking machine characteristics, and milking practices in a sample of Brazilian dairy herds.

1. Aspects of the influence of predation on the African buffalo Syncerus caffer were studied in Lake Manyara National Park, northern Tanzania, from 1981 to 1985. 2. During the study period, predation by lions was the most important cause of death in buffalo but occasionally major epidemics, such as rinderpest, can be by far the most important cause of death. 3. A comparison of Manyara with four other areas in Africa shows that the Manyara buffalo ran the same level of risk as those in these other areas, and that in periods in which epidemics or drought conditions are absent it was normal that ultimately some 90% of the large herbivores fell victim to predation. 4. Juvenile mortality in females was higher than in males but adult mortality in females was lower than in males. Adult bulls ran a much higher risk to be killed by lions (12.9% p.a.) than herd-living buffalo (4.4% p.a.); the latter category comprised cows and sub-adult bulls. 5. Risk of predation was highest near the ecotone between grasslands and structurally closed vegetations. Grasslands were as dangerous as woodlands and thickets, and only the mudflats were really safe. The chance to be killed fell steeply away from (potential) cover for lions. 6. Buffalo were more vigilant at night than during the day, peripheral animals more so than central ones. Adult bulls were more vigilant than other categories of buffalo. It is concluded that vigilance in buffalo was not restricted to predator detection. 7. The choice of feeding areas in buffalo was not dictated by predation risk alone.

Bivariate analysis of conception rates and test-day milk yields in Holsteins using a threshold-linear model with random regressions

Movement patterns of lions (Panthera leo) reveal how they hunt large herbivores in heterogeneous landscapes such as the Kruger National Park in South Africa. Large herbivores are distributed differently on the landscape and therefore have different vulnerabilities as prey for lions. For instance, blue wildebeest (Connochaetes taurinus) occupy small grazing lawns at night but are difficult for lions to capture because open areas lack cover for stalking. African buffalo (Syncerus caffer) aggregate in large herds but are less available because these herds only intermittently enter the home ranges of individual lion prides. Unlike large herds of wildebeest and buffalo, plains zebra (Equus quagga) move widely in small herds while browsing greater kudus (Tragelaphus strepsiceros) and giraffes (Giraffa camelopardalis giraffa) generally occur in lower densities. We used spatial data derived from GPS collars to investigate several hypotheses regarding the movements of three lion prides in response to their prey. We found that lions were most active and moved longer distances during nighttime than during daytime. Lions remained within their core home ranges on 87% of nights and wandered to the outlying areas of the home ranges every second night. Lions visited grazing lawns, that is, area of short grass, where wildebeest herds resided every second night, and moved toward the direction of buffalo herds within 2 km of vicinity. Lions spent more time near riverbanks that provided dense woody cover at night than expected but concentrated only weakly near sites with surface water where herbivores drank in the dry season. Our study contributes to understanding how lions vary their movements in response to the spatial and temporal heterogeneity in the relative availability and vulnerability of multiple prey species.

Opinions and Practices of Wisconsin Dairy Producers About Biosecurity and Animal Well-Being

The objective of this study was to assess the health status and the most common health problems occurring in beef cattle in the Czech Republic. Thirty five beef herds of different breeds were monitored from 1 January to 31 December 2006. The health status of 4872 animals (2601 cows and 2271 of their calves) was analyzed. Herds of up to 50 cows and those over 50 cows were evaluated both separately and together. Farm management data were collected by means of a questionnaire completed by the farmers. Both geographic and herd characteristics were evaluated, as well as the course of calving, mortality and morbidity in calves, and disease occurrence in cows. Calving was unassisted in about 80% of the cows, and the conception rate was approximately 90%. More difficult courses of calving were reported from the small herds than from the large ones (p < 0.001). Total calf losses were 10% on the average. Most calf deaths occurred during the first week of life (p < 0.01), the most common cause of death being diarrhoea (p < 0.001). The situation was similar in large and small herds. Diarrhoea was also most often diagnosed in those calves that survived the early life stage. At the age of 120 days, the calves that had suffered from diarrhoea showed a lower body weight by 12.6 kg than the calves of the same age from the same herd that did not have diarrhoea. The occurrence of diarrhoea in small and large herds was 12.1% and 6.7% per herd, respectively (p < 0.05). Also, other health disorders were more often reported from small herds, in calves as well as in adult cows (p < 0.001).

Patterns of association in many ungulate species vary throughout the year, with males periodically segregating from females. Sexual segregation can occur if males and females use different habitats (habitat segregation), occupy exclusive ranges (spatial segregation) or occur in separate social groups (social segregation). Previous studies on social segregation in ungulates have focused mostly on non‐reproductive periods and species in temperate systems with short mating seasons. This study examined social segregation in African buffalo Syncerus caffer at Hluhluwe‐iMfolozi Park, South Africa, during their 6‐month mating season. During this period, mature male buffalo alternated between joining mixed‐sex herds which comprise females and young, and small all‐male groups. Activity patterns of male buffalo in both group types were examined to determine if differences in time allocation or activity asynchrony could explain the observed segregation. Mature males foraged for less time than both adult females and younger males when they were with mixed herds. Mature male buffalo differed in how their active time was apportioned to foraging and reproductive activities between the two group types. Females maintained group cohesion despite only low synchrony in activity, therefore segregation of male buffalo could not be explained by the activity budget hypothesis. For males in mixed‐sex herds, reproductive activities were apparently at the expense of foraging time. The high time and energy costs of reproductive activities were probably responsible for the periodic separation of male buffalo from mixed herds during the extended mating period.

Documenting within species group size variation is important to completely understand social organization within species and to interpret variation among species. Here, I investigated group size of African buffalo Syncerus caffer over 2 years in a heterogeneous landscape. African buffalo use closed continuous forest and vast open savannas, and anecdotal observations suggest that habitat type influences their social structure. While the Cape buffalo Syncerus caffer caffer is well studied, few data exist for the forest‐dwelling Syncerus caffer nanus. I observed forest buffalo at Lopé National Park, Gabon, and examined variation of group size. Eighteen forest buffalo herds used the study area with an estimated population of 342 individuals (∼5 buffalo km−2). The mean group size for the 18 herds was 12 ± 2 (range of means=3–24), considerably smaller than Cape buffalo herds. For eight radiocollared forest buffalo, the mean group size was stable, varying little with time of day, across seasons, or between savanna and marsh habitat. However, herd size varied widely across herds, from fewer than 10 individuals in the smallest herds to more than 20 buffalo in the largest. Large herd size is associated with home ranges that contain substantial areas of open habitat, and thus more food resources than forested habitats.

The objectives of the present study were to explore the trend in preweaning mortality (PWM) and related measurements such as piglets born alive (PBA), stillborn piglets, herd productivity and herd size in sow herds over a 10-year period; and 2) to examine the relationships between PWM and the related measurements. Herd-level annual data from 2007–2016 for 91 herds in Spain were abstracted from a sow database compiled by a veterinary consultancy firm. The database software automatically calculated herd-level PWM (%) as follows: the total number of piglets born alive to a sow completely weaned during a year (TPBA) minus the total number of piglets weaned by the completely weaned sow during the year divided by TPBA x 100. All the statistical analyses were performed using SAS University Edition. A growth curve model was applied to incorporate correlations for all of the observations arising from the same farm. Herd means of PWM (SD) increased from 11.9 (4.1) % to 14.4 (3.2) %, and mean PBA increased by 1.9 pigs. Mean age of piglet death during lactation increased by 3.8 days, and there was a significant effect of increased year on herd size and the number of piglets weaned per sow per year (PSY; P < 0.05). Higher PWM was associated with more PBA, more stillborn piglets and small herds (lower than the median size: < 570 sows; P < 0.05). Also, as PBA increased from 9 to 14 pigs, PWM in large herds (> 570 sows) increased by only 6.6%, compared with 9.6% in small herds. Furthermore, as PWM decreased from 18 to 8%, herd productivity measured as PSY increased by 2.2 pigs in large herds, but only by 0.6 pigs in small herds. In conclusion, the effect of increased PBA on PWM was alleviated more in large herds than in small herds. Also, the impact of decreased PWM on herd productivity was greater in large herds than in small herds.

Pregnancy rates and sexual behavior under pasture breeding conditions in mares

Some aspects of the well-described planet- and satellite-like framework of, respectively, mixed herds and bachelor groups of buffalo recently were challenged. Associations of female buffalo are now considered more fluid than the initial idea of a stable mixed herd defined by a home range. Within mixed herds, adult female associations are unstable and transient despite using largely overlapping home ranges. Mixed herds in most instances do not seem to overlap much in space. Between mixed herds exchanges exist, apparently dominated by juvenile females (but almost no information exists on juvenile males). The dynamics of fusion–fission events within mixed herds are largely driven by habitat heterogeneity, the quality and quantity of grazing and surface water, and the influence of predation, parasitism and fires. The influence of the human/buffalo interface on these dynamics is not yet well understood. Future studies will benefit from more advances in telemetry and new technologies, new information sources (e.g. sound recorders) and non-invasive genetic studies to enhance our knowledge of buffalo social dynamics. Knowledge of buffalo social dynamics would also benefit from studies more representative of the African distribution of the species and across its subspecies.