Predicting Feed Intake of Fallow Deer (Dama Dama) Using Alkanes as a Marker

Ru, Y.J.,Miao, Z.H.,Glatz, P.C.,Choct, M. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.2

The understanding of seasonal forage intake of grazing deer is essential for the development of supplementary feeding strategies in southern Australia. The alkane technique is used in other animal species for estimating feed intake of individual animals and their diet composition. To assess the potential of using alkanes as a marker for predicting feed intake of fallow deer, the daily faecal recovery of alkanes and excretion rate of dosed artificial alkanes (C32 and C36) were measured with 6 deer fed three forage based diets. The artificial alkane capsule designed for use in sheep is suitable for fallow deer. Faecal samples need to be collected over days 7-19 after dosing. The daily excretion rate was 40 mg for C32 and 37 mg for C36. The faecal recovery of natural alkanes is incomplete and the faecal concentrations of alkanes need to be adjusted for an accurate estimation of intake. The actual feed intake of 6 experimental deer over a 5 day period was accurately estimated ($R^2$=0.52) using alkanes.

Effect of Salt Level in the Feed on Performance of Red and Fallow Weaner Deer

Ru, Y.J.,Fischer, M.,Glatz, P.C.,Bao, Y.M. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.5

In Australia, many cropping areas are affected by salt. In these regions, Chenopodiaceous plants, such as Atriplex, Kochia and Bassia spp have been planted to improve soil conditions. These plants have become invaluable feed resources for grazing animals in dry summers, but have a high sodium content. To assess the impact of high salt intake on grazing deer, two experiments were conducted. The first experiment used 30 fallow weaner deer to examine the effect of salt level in the diet on feed intake, water intake and body weight of fallow deer. Salt was added to lucerne chaff at 0, 1.5, 3.0, 4.5 and 6% and fresh water was offered all the time. Increasing the salt level in the diet from 0 to 6% didn't affect feed intake, osmotic pressure and mineral concentration in blood of fallow deer. However, water intake was significantly higher (p<0.05) in deer fed diets containing more than 3% salt. Body weight was lower (p${\leq}$0.056) for fallow deer in July and August when salt content was over 3%, suggesting they can ingest over 15 g sodium/day without significant depression in both feed intake and growth rate if the fresh water is available. In the second experiment, 18 red weaner deer were fed lucerne chaff diets containing 1.5, 4.5 and 6.0% salt with 6 deer/diet. The results revealed that feed intake and blood osmotic pressure were similar (p>0.05) for red deer fed different levels of salt although the feed intake declined from 1.91 to 1.67 kg with the increase of salt level from 1.5% to 6.0% in the diet. Water intake was significantly higher for deer fed diets containing over 4.5% salt, but there was no difference in body weight during the experiment. However, no recommendation can be made on the salt tolerance of red deer due to limited increment of salt level in the diet.

Comparison of the Digestibility of Grain and Forage by Sheep, Red and Fallow Deer

Ru, Y.J.,Glatz, P.C.,Miao, Z.H.,Swanson, K.,Falkenberg, S.,Wyatt, S. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.6

Two experiments were conducted to compare digestibility of 12 diets in sheep, red and fallow deer. No differences (p>0.05) between sheep, red and fallow deer in digestibility of dry matter, organic matter and digestible energy content for all diets were found except for the sorghum diet and medic hay. Sheep and fallow deer digested the sorghum diet better than red deer. An in vitro study showed that sheep had a lower in vitro dry matter digestibility and digestible energy content than both red and fallow deer, with a significant interaction between animal species and feed ingredient. Deer digested straws and hays better (p<0.05) than sheep. In vitro digestibility was lower (p<0.05) than in vivo digestibility, but significantly correlated with in vivo digestibility for red and fallow deer. The in vitro method for digestibility estimation has potential as a rapid feed evaluation system for deer, but needs further validation.

Application of Near Infrared Spectroscopy (NIR) for Monitoring the Quality of Milk, Cheese, Meat and Fish - Review -

Ru, Y.J.,Glatz, P.C. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.7

The traditional methods for determining the quality of milk, cheese and meat are tedious and expensive, with a significant wastage of chemicals which pollute the environment. To overcome these disadvantages, the potential of near infrared spectrophotometry (NIR) for monitoring the quality of milk and meat has been evaluated by a number of researchers. While most studies indicate that NIR can be used to predict chemical composition of milk and meat, and to monitor the cutting-point during cheese manufacturing, one study demonstrated the potential of NIR to predict sensory characteristics (e.g. hardness and tenderness) of beef. These calibrations were developed on a small number of samples, limiting their value for adoption by the industries. Now that the sophisticated computer software is available, more robust calibrations need to be developed to monitor both chemical and physical characteristics of meat and meat products simultaneously.

Forage Intake and Nutrient Requirements of Fallow Weaner Deer in Southern Australia

Ru, Y.J.,Fischer, M.,Glatz, P.C.,Wyatt, S.,Swanson, K.,Falkenberg, S. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.5

Information on nutrient requirements and forage intake of fallow weaner deer is required for the development of feeding strategies during the year. An experiment was conducted in which 60 fallow weaner deer (grazing on medic and ryegrass based pastures) were supplemented with a concentrated diet at three levels. The diet contained 2% minerals, 30% lupin and 68% barley grain. Twelve deer from each treatment were dosed with commercial alkane capsules in May, June, July, September and October to predict nutrient intake. The relationships between body weight gain and intake of metabolisable energy and crude protein were established using a general linear models analysis. Dry matter intake from pastures ranged from 0.137 kg to 0.304 kg in May and June and increased to 1.2 kg in October. Nutrient intake from pastures was strongly influenced by amount of supplementary feed and gender. Digestible energy intake from pastures was 1.3, 3.8 and 6.1 MJ/day higher for males than females in July, August and October, respectively. The protein and energy intake was strongly correlated with body weight gain. The energy requirement for maintenance were 7.3, 8.2, 10.2, 10.2 and 10.7 MJ DE/day and the DE required for each kg body weight gain were 19, 18, 29, 34 and 49 MJ in May, June, August and October, respectively. The protein requirement for maintenance was 12.2, 12.6, 15.0, 11.4 and $8.5g/W^{0.75}$ in May, June, July, August and October, respectively. The nutrient requirement defined from this study can be used to assist farmers to explore the possible pasture and stock management practices under southern Australian conditions. However, further research is required to develop rapid and cheap methods for estimating dry matter intake, nutritive value of pastures and to quantify the potential growth rate of fallow deer in southern Australia.

Variation in Nutritive Value of Commercial Broiler Diets

Ru, Y.J.,Hughes, R.J.,Choct, M.,Kruk, J.A. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.6

The classical energy balance method was used to measure the apparent metabolisable energy (AME) of four batches of broiler starter and finisher diets produced by two commercial feed companies. The results showed there was little variation in protein content between batches, but NDF content varied from 13.3% to 15.5% between batches of diet. The batch variation in chemical composition differed between feed manufacturers. While there was no difference in AME and feed conversion ration (FCR) between batches of starter diets produced by company A, FCR and AME ranged from 1.76-1.94 (p<0.001) and 11.38-11.90 MJ/kg air dry (p<0.05), respectively, for diets produced by company B. Similar results were found in a second experiment. There was no difference in AME, dry matter digestibility (DMD) and FCR between batches for finishing diet produced by company B, but a large variation occurred for the finisher diets from company A (p<0.01), where the ranges of FCR, AME and DMD were 1.95-2.30, 10.5-12.3 (MJ/kg air dry) and 58-68%, respectively. FCR was correlated with AME. AME was negatively related to the content of fibre in the diet, but positively related to DMD. The preliminary results based on 24 samples showed that near infrared spectroscopy (NIR) has the potential to predict FCR, intake, AME and DMD of commercial broiler diets, with $R^2$ being 0.93, 0.89, 0.95 and 0.98, respectively. The standard error of cross validation was below 0.2 for AME and only 0.06 for FCR.

Sward Characteristics and Nutritive Value of Two Cultivars of Subterranean Clover

Ru, Y.J.,Fortune, J.A. Asian Australasian Association of Animal Productio 1999 Animal Bioscience Vol.12 No.8

Two cultivars of subterranean clover (Trifolium subterraneum L.), "Dinninup" and "Seaton Park" were sown at Shenton Park Field Station, Western Australia, in May 1992 and 1993. The characteristics of Dinninup related to animal production were compared with Seaton Park under grazing conditions with herbage utilization efficiencies of 60% in 1992 and 65% in 1993. The results showed that Dinninup and Seaton Park had similar dry matter digestibility (77-78%) and dry matter production (1,290 kg/ha in 1992; 930 kg/ha in 1993) before flowering initiation even though Dinninup had more (p<0.05) branches, leaves and petioles per plant. After flowering, the herbage on offer of Dinninup was higher (p<0.05) and dry matter digestibility was lower (p<0.05) than that of Seaton Park while the sward structure was similar for both cultivars. The variation in nutritive value among plant parts increased with maturation. Leaf was more digestible than stem and petiole with a higher nitrogen content, and stem had the lowest dry matter digesitibility and nitrogen content in late of the season. Sheep did not show any preference for Seaton Park over Dinninup. The predicted bodyweight gain of sheep grazing pure Seaton Park and Dinninup swards using Grazfed software indicated that sheep grazing Dinninup were predicted to have a similar bodyweight gain in early growing stage and a significantly lower gain after flowering compared with those grazing Seaton Park.

Effect of Salt Level in Water on Feed Intake and Growth Rate of Red and Fallow Weaner Deer

Ru, Y.J.,Glatz, P.C.,Bao, Y.M. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.1

Under a typical Mediterranean environment in southern Australia, the evaporation rate increases significantly in hot summers, resulting in highly saline drinking water for grazing animals. Also in the cropping areas, dryland salinity is a problem. Grazing animals under these environments can ingest excessive amount of salt from feed, drinking water and soil, which can lead to a reduction in growth rate. To understand the impact of high salt intake on grazing deer, two experiments were conducted to assess the effect of salt levels in drinking water on feed intake and growth rate of red and fallow weaner deer. The results revealed that fallow deer did not show any abnormal behaviour or sickness when salt level in drinking water was increased from 0% to 2.5%. Feed intake was not affected until the salt content in water exceeded 1.5%. Body weight gain was not affected by 1.2% salt in drinking water, but was reduced as salt content in water increased. Compared with deer on fresh water, the feed intake of red deer on saline water was 11-13% lower when salt level in drinking water was 0.4-0.8%. An increase in salt level in water up to 1% resulted in about a 30% reduction in feed intake (p<0.01). Body weight gain was significantly (p=0.004) reduced when salt level reached 1.2%. The deer on 1% salt tended to have a higher (p=0.052) osmotic pressure in serum. The concentration of P, K, Mg and S in serum was affected when salt level in water was over 1.0%. The results suggested that the salt level in drinking water should be lower than 1.2% for fallow weaner deer and 0.8% for red weaner deer to avoid any reduction in feed intake. Deer farmers need to regularly test the salt levels in drinking water on their farms to ensure that the salt intake of grazing deer is not over the levels that deer can tolerate.

Predicting N-alkane Concentration in Pastures and Deer Faeces for Dietary Composition and Digestibility Measurement Using Near Infrared Spectroscopy

Ru, Y.J.,Kruk, J.A.,Fischer, M.,Choct, M.,Glatz, P.C. Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.11

The alkanes in plant materials can potentially be used as markers to estimate composition and digestibility of diet of deer for the development of feeding strategies, but the analysis of alkanes in plant materials and deer faeces is time-consuming and expensive. In this study, 242 faecal samples and 119 pasture samples were scanned using near infrared spectroscopy (NIR) and the concentrations of alkanes in these samples were analysed to develop calibrations for predicting alkane concentrations in pastures and deer faeces. The $R^2$ values for NIR calibrations were <0.6 for $C_{24}$, $C_{26}$, $C_{32}$ and $C_{36}$, but were >0.8 for other alkanes for faecal samples. The $R^2$ values were >0.87 for alkanes with chains from $C_{27}$ to C35 for pasture samples. However, NIR was unable to predict concentrations of alkanes with chains of $C_{24}$, $C_{26}$, $C_{32}$ and $C_{36}$ in faecal samples and $C_{24}$, C25, $C_{26}$ and $C_{36}$ in pasture samples. While the use of these NIR calibrations will accelerate the estimation of diet digestibility, dietary components and botanical composition of pastures, the influence of the type of pasture on NIR calibration will require further examination.

Impact of Salt Intake on Red and Fallow Deer Production in Australia - Review -

Ru, Y.J.,Glatz, P.C.,Miao, Z.H. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.12

Southern and south-western Australia is a typical mediterranean environment, characterised by wet, cold winters and dry, hot summers. The evaporation rate varies significantly in summer, resulting in a high salinity of drinking water for grazing animals. In addition, a large amount of land in the cropping areas is affected by salt. Puccinellia, tall wheat grass and saltbushes have been planted to improve the soil condition and to supply feed for grazing animals. Animals grazing these areas often ingest an excessive amount of salt from soil, forage and drinking water which can reduce feed intake, increase the water requirement, depress growth and affect body composition as demonstrated in sheep. While the deer industry has been successfully developed in these regions, the potential impact of excessive salt intake on deer production is unknown. The salt tolerance has been well defined for sheep, cattle and other livestock species, but the variation between animal species, breeds within species, maturity status and grazing environments makes it impossible to apply these values directly to deer. To optimise deer production and effectively use natural resources, it is essential to understand the salt status of grazing deer and the impact of excessive salt intake on growth and reproduction of deer.