Effect of Post-Grazing Sward Height, Sire Genotype and Indoor Finishing Diet on Steer Intake, Growth and Production in Grass-Based Suckler Weanling-to-Beef Systems

This study evaluated the effects of post-grazing sward height (PGSH, 4 or 6 cm) on herbage production, its nutritive value, dry matter (DM) intake, grazing behaviour and growth of early- (EM) and late-maturing (LM) breed suckler steers (n = 72), and the subsequent effect of indoor finishing diet (grass silage + 3.8 kg concentrate DM/head daily (SC), or grass silage only (SO)) on performance and carcass traits. Animals rotationally grazed pasture for 196 days, followed by indoor finishing for 119 days. At pasture, daily live-weight gain (LWG) was 0.10 kg greater for PGSH-6 than PGSH-4, resulting in a tendency for carcass weight to be 11 kg heavier. Although EM had a 0.10 kg greater daily LWG at pasture than LM, carcass weight did not differ between the genotypes. There was a genotype × PGSH interaction for carcass fat score, whereby there was no difference between EM-4 (8.83, 15-point scale) and EM-6 (8.17), but LM-6 (7.28) was greater than LM-4 (6.33). Although concentrate supplementation during indoor finishing increased carcass weight (+37 kg) and fat score (1.75 units), the majority of steers (83% of EM and 78% of LM) achieved a commercially-acceptable carcass fat score (6.78) at slaughter in the grass-forage-only system.

Seroprevalence of Toxoplasma gondii in aborted goats in Kerala

Toxoplasmosis, is a cosmopolitan zoonotic parasitic infection prevalent throughout the world affecting all warm blooded animals and man. A total of 72 serum samples from goats belonging to the organised, unorganised and small holder farms that had aborted recently or had a history of abortion were collected from the central districts of Kerala viz., Palakkad, Thrissur and Ernakulam. The samples were subjected to indirect Enzyme Linked Immunosorbent Assay (ELISA) for the detection of IgG antibodies of Toxoplasma gondii. Factors predisposing to the prevalence of infection such as age, grazing behaviour and stage of gestation were also taken into account during the study. Out of 72 serum samples examined, 31(43 per cent) were negative, 13 (18 per cent) were weakly positive and 28 (38.88 per cent) were highly positive. A higher prevalence was noticed in goats above four years of age, in those with regular grazing behaviour and in those that had aborted in the second stage of gestation. District-wise prevalence revealed relatively higher prevalence in Ernakulam district (62.5 per cent) compared to Thrissur (56.09 per cent) and Palakkad (53.33 per cent), even though the difference was not statistically significant.

Grazing behaviour and forage selection pattern of heifers in the range

The grazing behaviour of eight yearling white Fulani heifers was studied in two season of year in the south western zone of Nigeria. Time spent on different activities such as drinking, walking, grazing, resting and ruminating were determined using direct eye observation technique. The types of forage selected in both seasons were identified. Visual observations revealed that behaviour was influenced by seasons. The heifers spent 2, 8, 15, 14 and 62% of their time drinking, ruminating, resting, walking and grazing respectively as overall percentage for the two seasons. The forage selection pattern revealed that forbs were mostly selected in the late dry season and grasses in the early rain season. The forages selected in the late dry season were Panicum maximum, Cynodon dactylon, Ipomea aquatical, Leucaena leucocephela, Centrosema mole and Althernanthera dentata. In the early rain season forages selected include Setaria bartata, Echinochloa stagirina, Pennisetum purpureum and Panicum maximum regrowth. It is therefore concluded that the study provides a quick insight into behavioural and forage selection pattern of heifers. Therefore the study can be used to assess grazing animal nutrition condition.

Finding and acquiring food.

This chapter describes grazing behaviour as an example of how feeding is organized; finding food; the ability to obtain food; meal size and food selection; the effects of disturbance on feeding; social facilitation; competition and feeding behaviour and some specific details about feeding in cattle, sheep, horses, dogs, cats, pigs and poultry.

Grazing behaviour - diet selection and pasture intake.

In this chapter the nutritional environment, foraging behaviour, feed intake, and diet selection of grazing animals are discussed.

Modelling seasonal pasture growth and botanical composition at the paddock scale with satellite imagery

Seasonal pasture monitoring can increase the efficiency of pasture utilization in livestock grazing enterprises. However, manual monitoring of pasture over large areas is often infeasible due to time and financial constraints. Here, we monitor changes in botanical composition in Tasmania, Australia, through application of supervised learning using satellite imagery (Sentinel-2). In the field, we measured ground cover and botanical composition over a twelve-month period to develop a supervised classification approach used to identify pasture classes. Across seasons and paddocks, the approach predicted pasture classes with 75-81% accuracy. Botanical composition varied seasonally in response to biophysical factors (primarily climate) and grazing behaviour, with seasonal highs in spring and troughs in autumn. Overall, we demonstrated that 10 m multispectral imagery can be reliably used to distinguish between pasture species as well as seasonal changes in botanical composition. Our results suggest that farmers and land managers should aim to quantify within-paddock variability rather than paddock average cover, because the extent and duration of very low ground cover puts the paddock/field at risk of adverse grazing outcomes, such as soil erosion and loss of pasture biomass, soil carbon and biodiversity. Our results indicate that satellite imagery can be used to support grazing management decisions for the benefit of pasture production and the improvement of environmental sustainability.

The Effect of Frequency of Fresh Pasture Allocation on Pasture Utilisation and the Performance of High Yielding Dairy Cows

Pasture allocation frequency (PAF) can influence pasture availability and grazing behaviour, which subsequently may impact on animal performance. Limited research to-date has investigated grazing management methods to improve the performance of high production dairy cows whilst also achieving high grass utilisation rates. This study evaluated the effect of three different PAF’s (12, 24 and 36 h) on pasture utilisation, the performance of high yielding dairy cows and the interaction with parity. The experiment included two 60-day periods, 90 spring calving dairy cows (27 primiparous animals) in period one and 87 (24 primiparous animals) in period two. The average pre-grazing sward height (11.4 cm) was similar for all treatments in both periods. In period one, pasture utilisation rate was significantly higher (8%) in the 36 h compared to the 12 h treatment. In period two, milk energy output was significantly greater for primiparous animals in the 36 h treatment relative to the other treatments.