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Item Meta-analysis of New Zealand's nitrous oxide emission factors for ruminant excreta supports disaggregation based on excreta form, livestock type and slope class.(Elsevier B.V., 2020-08-25) van der Weerden TJ; Noble AN; Luo J; de Klein CAM; Saggar S; Giltrap D; Gibbs J; Rys G; Jenerette DGlobally, animal excreta (dung and urine) deposition onto grazed pastures represents more than half of anthropogenic nitrous oxide (N2O) emissions. To account for these emissions, New Zealand currently employs urine and dung emission factor (EF3) values of 1.0% and 0.25%, respectively, for all livestock. These values are primarily based on field studies conducted on fertile, flatland pastures predominantly used for dairy cattle production but do not consider emissions from hill land pastures primarily used for sheep, deer and non-dairy cattle. The objective of this study was to determine the most suitable urine and dung EF3 values for dairy cattle, non-dairy cattle, and sheep grazing pastures on different slopes based on a meta-analysis of New Zealand EF3 studies. As none of the studies included deer excreta, deer EF3 values were estimated from cattle and sheep values. The analysis revealed that a single dung EF3 value should be maintained, although the value should be reduced from 0.25% to 0.12%. Furthermore, urine EF3 should be disaggregated by livestock type (cattle > sheep) and topography (flatland and low sloping hill country > medium and steep sloping hill country), with EF3 values ranging from 0.08% (sheep urine on medium and steep slopes) to 0.98% (dairy cattle on flatland and low slopes). While the mechanism(s) causing differences in urine EF3 values for sheep and cattle are unknown, the 'slope effect' on urine EF3 is partly due to differences in soil chemical and physical characteristics, which influence soil microbial processes on the different slope classes. The revised EF3 values were used in an updated New Zealand inventory approach, resulting in 30% lower national N2O emissions for 2017 compared to using the current EF3 values. We recommend using the revised EF3 values in New Zealand's national greenhouse gas inventory to more accurately capture N2O emissions from livestock grazing.Item Cross-species transmission of coronaviruses with a focus on severe acute respiratory syndrome coronavirus 2 infection in animals: a review for the veterinary practitioner.(Taylor and Francis Group, 2023-07-01) Dunowska MIn 2019 a novel coronavirus termed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged from an unidentified source and spread rapidly among humans worldwide. While many human infections are mild, some result in severe clinical disease that in a small proportion of infected people is fatal. The pandemic spread of SARS-CoV-2 has been facilitated by efficient human-to-human transmission of the virus, with no data to indicate that animals contributed to this global health crisis. However, a range of domesticated and wild animals are also susceptible to SARS-CoV-2 infection under both experimental and natural conditions. Humans are presumed to be the source of most animal infections thus far, although natural transmission between mink and between free-ranging deer has occurred, and occasional natural transmission between cats cannot be fully excluded. Considering the ongoing circulation of the virus among people, together with its capacity to evolve through mutation and recombination, the risk of the emergence of animal-adapted variants is not negligible. If such variants remain infectious to humans, this could lead to the establishment of an animal reservoir for the virus, which would complicate control efforts. As such, minimising human-to-animal transmission of SARS-CoV-2 should be considered as part of infection control efforts. The aim of this review is to summarise what is currently known about the species specificity of animal coronaviruses, with an emphasis on SARS-CoV-2, in the broader context of factors that facilitate cross-species transmission of viruses.Item Molecular typing of Leptospira spp. in farmed and wild mammals reveals new host-serovar associations in New Zealand.(Taylor and Francis Group, 2024-01-01) Wilkinson DA; Edwards M; Shum C; Moinet M; Anderson NE; Benschop J; Nisa SAIMS: To apply molecular typing to DNA isolated from historical samples to determine Leptospira spp. infecting farmed and wild mammals in New Zealand. MATERIALS AND METHODS: DNA samples used in this study were extracted from urine, serum or kidney samples (or Leptospira spp. cultures isolated from them) collected between 2007 and 2017 from a range of domestic and wildlife mammalian species as part of different research projects at Massey University. Samples were included in the study if they met one of three criteria: samples that tested positive with a lipL32 PCR for pathogenic Leptospira; samples that tested negative by lipL32 PCR but were recorded as positive to PCR for pathogenic Leptospira in the previous studies; or samples that were PCR-negative in all studies but were from animals with positive agglutination titres against serogroup Tarassovi. DNA samples were typed using PCR that targeted either the glmU or gyrB genetic loci. The resulting amplicons were sequenced and typed relative to reference sequences. RESULTS: We identified several associations between mammalian hosts and Leptospira strains/serovars that had not been previously reported in New Zealand. Leptospira borgpetersenii strain Pacifica was found in farmed red deer (Cervus elaphus) samples, L. borgpetersenii serovars Balcanica and Ballum were found in wild red deer samples, Leptospira interrogans serovar Copenhageni was found in stoats (Mustela erminea) and brushtail possums (Trichosurus vulpecula), and L. borgpetersenii was found in a ferret (Mustela putorius furo). Furthermore, we reconfirmed previously described associations including dairy cattle with L. interrogans serovars Copenhageni and Pomona and L. borgpetersenii serovars Ballum, Hardjo type bovis and strain Pacifica, sheep with L. interrogans serovar Pomona and L. borgpetersenii serovar Hardjo type bovis, brushtail possum with L. borgpetersenii serovar Balcanica, farmed deer with L. borgpetersenii serovar Hardjo type bovis and hedgehogs (Erinaceus europaeus) with L. borgpetersenii serovar Ballum. CONCLUSIONS: This study provides an updated summary of host-Leptospira associations in New Zealand and highlights the importance of molecular typing. Furthermore, strain Pacifica, which was first identified as Tarassovi using serological methods in dairy cattle in 2016, has circulated in animal communities since at least 2007 but remained undetected as serology is unable to distinguish the different genotypes. CLINICAL RELEVANCE: To date, leptospirosis in New Zealand has been diagnosed with serological typing, which is deficient in typing all strains in circulation. Molecular methods are necessary to accurately type strains of Leptospira spp. infecting mammals in New Zealand.Item Smooth muscle hamartoma in a castrated male red deer (Cervus elaphus) in New Zealand.(Taylor and Francis Group, 2023-07-01) Johnson SG; Fermin LM; Aberdein D; Lawrence KEReports of neoplasia in deer remain rare (Hill and Staples Citation1999), despite the conviction that as deer farming became more common, a greater number of pathological processes, including tumours, would be recognised in deer (Pérez et al. Citation1998). Skin tumours are among the most common neoplasms reported in red deer (Cervus elaphus) and are usually papillomavirus-associated dermal fibropapillomas and papillomas (Erdélyi et al. Citation2009; Vaatstra et al. Citation2014; Garcês et al. Citation2020). Additional reports of cutaneous and subcutaneous tumours in red deer include malignant schwannoma and dermal malignant melanoma (Pérez et al. Citation1998; Scandrett and Wobeser Citation2004). In related deer species, subcutaneous dermoid cysts have been described in caribou (Rangifer tarandus) (Wobeser et al. Citation2009) and cutaneous fibromas in predominantly male white-tailed deer (Odocoileus virginianus) (Berry Citation1925; Friend Citation1967; Sundberg and Nielsen Citation1982).Item Venison and velvet production from Red and hybrid deer by one year of age : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Animal Science at Massey University, New Zealand(Massey University, 1996) Min, Byeng-RyelA grazing experiment was conducted at Massey University Deer Research Unit, Palmerston North, New Zealand during 1995, to study the effects of grazing chicory (Cichorium intybus), Lotus comiculatus and perennial ryegrass (Lolium perenne)lwhite clover (Trifolium repens) pasture upon the growth, voluntary feed intake (VFI), venison and velvet production of red and hybrid (0.75 red;0.25 elk) deer from weaning to slaughter at one year of age. The animals were randomly allocated to graze either chicory, lotus or pasture and grazed these forages during autumn and spring using a rotational grazing system, with each group balanced for genotype and sex. All groups were joined to graze pasture during winter, when chicory and lotus were dormant. 1. Few animals attained the target slaughter weight (50kg carcass or greater) when grazing pasture and spiker velvet antler weight was low at approximately 0.2 kg per stag. 2. In this study the greatest advantages obtained for specialist forages were for chicory. Carcass weight of deer grazing chicory was higher than for deer grazing pasture, due mainly to increasing autumn LWG and dressing-out percentage at slaughter, with a smaller response in spring LWG. The largest carcass weights were consistently obtained from hybrid stags grazing on chicory, with values for red deer and hybrid stags being 56.0 and 59.3 kg when grazed on chicory and 48.6 and 53.3 kg respectively when grazed on pasture. Chicory had a higher organic matter digestibility (OMO) and VFI than pasture during autumn but similar values in spring, accounting for its autumn growth stimulation. Carcass subcutaneous fat depth (GR) was higher for deer grazing chicory than pasture, but after being adjusted to equal carcass weight, there was no difference in GR measurement. Relative to deer grazing on pasture, grazing on chicory increased total spiker velvet antler production (323 v 225 g/stag), by advancing the dates of pedicle initiation (18 days), velvet antler initiation (24 days), and first velvet cutting (17 days) and increasing the rate of velvet antler length growth. Initiation of velvet growth was correlated with liveweight, with each 10 kg increase in liveweight advancing the dates of pedicle initiation, commencement of velvet growth and first velvet cutting by 10, 18 and 13 days respectively. Correction of the data to equal liveweight removed a component of the advancement produced from feeding on chicory, but an effect still remained due to chicory feeding per se. It was concluded that grazing chicory not only increased carcass weight (especially in hybrid stags), but also increased velvet antler production. This was achieved by increased VFI and increased OMO of chicory in autumn, relative to deer grazing pasture, and probably by increased absorption of protein and minerals in deer fed chicory. 3. OMO of lotus was higher than that of pasture during autumn, but not in spring. The OMO of either chicory or lotus showed little change between seasons, but pasture changed with the season, being of lowest OMO in autumn and highest OMO in spring. 4. Responses to deer grazing lotus were limited by the reduced number of grazing days that could be achieved, due to problems in lotus establishment. In spite of these problems, grazing lotus (48 gCT/kg OM) did increase the LWG of stags during autumn (248 v 176 g/day) and increased the efficiency of growth in spring, with LWG being similar to deer grazing pasture, but VFI being lower (1.53 v 2.00 kgOM/day) for lotus compared to pasture. Although deer grazing lotus had a similar carcass weight compared to deer grazing pasture, dressing-out percentages of deer grazing lotus were higher than that of deer grazing pasture (56.4 v 53.2 %). The carcass GR tissue depth of deer grazing lotus had similar values compared to pasture. There was no interaction between forage and genotype for carcass weight and dressing out percentage. Stags grazing lotus did not show any advancement in dates of pedicle initiation, velvet antler initiation and weight of velvet production compared to stags grazing pasture. 5. Total condensed tannin (CT) concentration in lotus was 48 and 13 g/kgOM in hand plucked and oesophageal fistulae (OF) extrusa samples respectively. Most CT in hand plucked lotus samples was extractable, with much smaller amounts being protein-bound or fibre-bound. Extractable CT was not detected in lotus OF extrusa samples, and the concentration of protein-bound and fibre-bound CT remained similar to hand plucked samples. Therefore, after chewing during eating, the extractable component of CT in lotus feed could not be extracted and detected by the Butanol/HCI analysis methods and may have been bound to deer salivary proteins. Total CT in both hand plucked and OF extrusa samples was 3.1 v 5.8 g/kgOM for chicory and 0.3 v 1.5 g/kgOM for pasture. As a result, chewing (in OF samples) did not reduce the CT content of pasture or chicory. This may be due to the low concentration of extractable CT (and high proportions of bound CT) in these forages, which may have limited access for the deer salivary CT-binding proteins. 6. Overall it was concluded that chicory was of very high feeding value (FV) and had excellent nutritional advantages for increasing deer production. However, crops of chicory need to have specialised grazing management to increase persistency. New chicory cultivars need to be selected to increase persistency and to reduce reproductive stem formation during summer. Effects of protein supply on initiation of pedicle and velvet antler development in weaner stags grazing fresh forages also needs to be studied. The small responses obtained in the present study give some indication that the CT content of Lotus comiculatus may have a number of values for improving the efficiency of growth in young deer. Further experiments are needed in this area.Item Venison production from weaner Red Deer (Cervus elaphus) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in the Department of Animal Science, Faculty of Agricultural and Horticultural Sciences, Massey University, Palmerston North, New Zealand(Massey University, 1993) Soetrisno, EdiForty four weaner red deer (Cervus elaphus) fawns (26 stags; 18 hinds) were used to investigate the effects of grazing pure red clover (Trifolium pratense) or perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) pastures and immunisation against melatonin upon growth and venison production, with the objective of the stags attaining a minimum target slaughter liveweight (92 kg LW;>50 kg carcass) by 12 month of age. The experiment was conducted at the Deer Unit Massey University, NZ, during 1991. The animals were randomly allocated into eight treatment groups (starting on 13 March 1991), with the combination of pasture types ((pure red clover (RC) or perennial ryegrass/white clover (PRG/WC), sex (male or female) and immunisation (against melatonin or placebo only). The deer were rotationally grazed on either RC or PRG/WC pasture (feed allowances 6, 7 kg DM/h/day, respectively) during autumn and spring. During winter, all animals were combined and grazed together on PRG/WC pasture (6 kg DM/h/day feed allowance), at a pasture residual DM of 1100 kg DM/ha. The subcutaneous anti-melatonin injections were administered to the immunisation groups at birth and at weaning. Pre-grazing herbage mass for RC or PRG/WC were respectively 3568, 3706 kg DM/ha in autumn; 2726, 2150 kg DM/ha in spring; 1736 kg DM/ha in winter. Post-grazing herbage mass for RC or PRG/WC averaged at 1822, 1882, in autumn; 1705, 1334, in spring; and 1170 kg DM/ha in winter, respectively. Total nitrogen (N) and organic matter digestibility (OMD) concentration of both feed on offer (FO) and diet selected (DS) were higher in RC than PRG/WC (FO total N: 3.4 vs 3.4% DM in autumn, 4.1 vs 2.6% DM in spring; FO OMD: 77.3 vs 78.6% OM in autumn, 84.5 vs 80.3% OM in spring; DS total N: 4.2 vs 3.9 % DM in autumn, 4.7 vs 3.3% DM in spring; DS OMD: 84.2 vs 83.2% OM in autumn, 87.7 vs 82.4% OM in spring). Liveweight gain (LWG) of RC stags and hinds was significantly higher than PRG/WC animals in autumn (237 vs 207; 197 vs 159 g/d; P<0.01) and in spring (346 vs 281; and 260 vs 188 g/d; P<0.001), but not in winter (94 vs 95; 38 vs 40 g/d; P>0.05). Weaner stags and hinds grazing RC forage had significantly higher voluntary feed intake (VFI) than the comparable animals grazing PRG/WC pasture in either autumn (P<0.05) or spring (P<0.001). By 12-month of age, stags grazing RC were 6 kg heavier and hinds 7 kg heavier than animals grazing PRG/WC forage. All (100%) RC stags attained the minimum target slaughter LW (>92 kg LW; 50 kg carcass) by 12-month of age at the end of November, compared to 90% of PRG/WC stags. Carcass weights (kg) and dressing percentage (%) of RC stags were significantly higher than PRG/WC stags (58.9 vs 53.3 kg, P<0.01; 56.2 vs 52.4%, P<0.001), but the carcass GR was not different (P>0.05) either after or before being adjusted to equal carcass weight. The immunisation treatment did not provide any significant responses (P>0.05) in LWG and did not affect plasma prolactin concentrations. The immunisation against melatonin treatment did not give any significant effects (P>0.05) on all measurements of carcass production. In conclusion, these studies show that early venison production from grazed PRG/WC pastures is possible, and that this can be further improved by inputs of RC. Weaner red deer grazing red clover forage during autumn and spring grew and produced venison better than animals grazing conventional PRG/WC pastures. The immunisation against melatonin did not provide any significant effects on growth and venison production from weaner red deer grazing either RC or PRG/WC forages. RC offers very good potential as a special purpose forage for venison production.Item Studies of some aspects of gastrointestinal nematodes and Dictyocaulus viviparus of farmed red deer : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University(Massey University, 1985) Anderson, Mark VereStudies were carried out on aspects of the treatment and control of gastrointestinal nematodes and D. viviparus in red deer, under New Zealand farming conditions. In addition, the relationship between faecal egg count and gastrointestinal worm count was investigated. In the first study an anthelmintic-impregnated supplementary feed treatment regime incorporating 200mg albendazole per kg of deer nuts (medicated nuts), fed to give 5mg albendazole per kg liveweight daily for three 10-day treatments with 21 day intervals between treatments, was given to eight weaner deer in the autumn. This treatment was compared with 3-weekly single oral administration of albendazole (10mg/kg) to eight similar deer under the same conditions (set-stocked in small pasture plots and given 2kg concentrate feed per head, per day) and a similarly treated group rotationally grazed on pasture alone. Reductions in faecal egg and larval counts were the same for all three groups, but reinfestation in spring was more rapid in the pasture-fed deer. Liveweights were the same for all groups throughout the experimental period from March to November. As an adjunct to this trial, medicated nuts were fed at the same dose-rate to 16 adult hinds. All faecal egg and larval counts were reduced to zero within 10 days. Thus, anthelmintic-impregnated concentrate feed is an effective way of controlling gastrointestinal and lung nematodes in deer. The above trial and another on a commercial property showed that high faecal larval counts may be found in weaner deer where deer are set-stocked from before calving up to weaning, or if parasite control programmes are delayed until six weeks after weaning in March. A single oral dose of albendazole at 10mg/kg was found to reduce D. viviparus faecal larval counts and gastrointestinal nematode faecal egg counts by approximately 99% seven days after treatment. Faecal larval and egg counts were usually slightly elevated 21 days after treatment, suggesting either a rapid reinfestation and short prepatent period of the parasites in deer and/or an efficacy of albendazole of less than 100% against immature stages of the gut and lung nematodes. In a third study, cutaneous application of levamisole (20% W/V) at a dose-rate of 10mg levamisole per kg was found to be ineffective in reducing faecal egg or larval counts in a group of 23 red deer under two years of age. The fourth study involved collection of abomasa and intestines of 46 deer sent to a deer slaughter premises. A faecal egg count was performed and the gastrointestinal nematodes were identified and counted. The largest gut parasite burdens were of Trichostrongylus axei with counts up to 12,900. Five deer-specific species of the tribe Ostertagiea, Spiculopteragia spiculoptera, Spiculopteragia asymmetrica, Ostertagia leptospicularis, Skrjabinagia kolchida and Skrjabinagia lyratiformis were also common (counts up to 2470). Few other parasites were found and numbers were low (0 to 90). The relationship between worm count and faecal egg count was described by the relationship: Total Worm Count = 18.8 (Faecal Egg Count) - 341. However, there were few deer with high worm and egg counts and this relationship must therefore be regarded as tentative until more work can be carried out in deer with high worm burdens.Item The effect of supplementation with ascorbic acid upon rumen metabolism and plasma ascorbic concentration in red deer (Cervus elaphus) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Nutritional Science at Massey University(Massey University, 2001) Gurusinghe, RanjanSix indoor experiments were conducted at the Massey University Deer Research Unit to study whether the blood plasma ascorbic acid (AA) concentration in farmed red deer (Cervus elaphus) could be raised, using a single oral or intraluminal administration of AA prior to a simulated slaughter situation. The work arose from the suggestion by Stevenson-Barry et al (1999) that feeding treatments be investigated for increasing the concentration of AA in venison, with a view to increasing colour stability and extending shelf life and from unpublished observations by these authors that it may be possible to achieve this from administering large single doses of AA before slaughter (J.M. Stevenson-Barry personal communication). Ruminal degradation of ascorbic acid was also studied, to establish a mechanism of how the single dose technique increased plasma AA concentration and particularly to identify the site of AA absorption. Seven ruminally fistulated male castrated red deer (average age 13 years) and three male castrated red deer fistulated in both the rumen and abomasum (average age 1.5-3.0 years) were individually fed chaffed lucerne hay ad libitum at 30 minute intervals throughout the experimental programme from July 1999 to February 2000. Animals were brought into metabolism cages one week before the administration of AA, orally or intraruminally. Feed was withdrawn 8 hours before AA was administered and fasting continued during the period of rumen and blood sampling (total 30 hours fasting). Ascorbic acid was administered as a 50:50 w/v suspension in water. Blood (jugular vein), rumen fluid and abomasal fluid samples were taken 15 minutes (min.) before each dose of AA and further samples were taken at 15 min., 30 min., 60 min., 2 hours (hr.) 4 h., 6 h., 8 h., 12 h., 16 h. and 22 h., after AA administration depending on the experiment. Voluntary feed intake (VFI) of individual deer was measured during the 3 days before dosing with AA in all experiments. Rumen fluid and abomasal fluid pH values were also recorded in Experiments 3, 4, 5 and 6. The liquid phase marker chromium complex of ethylenediaminetetra-acetic acid (Cr-EDTA) was administered with and without AA given intraruminally in Experiment 6, to measure rumen liquid fractional outflow rate (FOR) and to calculate the proportion of AA dosed that flowed into the abomasum. The animals grazed perennial ryegrass/ white clover pastures for periods of 1 to 2 weeks between individual experiments. 1. Experiment 1 and 2 were conducted to determine an appropriate dose rate of orally/ intraruminally administered AA to obtain high concentration of AA in rumen fluid and blood plasma and to define an appropriate time interval between repeat doses of AA. A range of oral and intraluminal doses of AA were given in Experiment 1 to individual deer and 2.8 g AA /kg liveweight was identified as a suitable dose to increase plasma AA concentration. At the end of Experiment 2, it was concluded that the use of a single intraluminal dose of 2.7 g AA equivalent/kg liveweight with repeat doses being a minimum of 2-weeks apart should be used for the remaining four experiments in order to obtain repeatable concentrations of AA in rumen fluid and blood plasma. In Experiment 2, dosing with AA depressed VFI for 4 days after its administration. 2. In Experiment 3, six rumen fistulated deer were used in a 3x3 Latin square experiment to study the best bioavailability of 3 different types of AA namely pure ascorbic acid (AA), ethyl cellulose coated ascorbic acid (EC) and silicone coated ascorbic acid (SC) using a single high dose technique. Pure AA and the other two derivatives were administered at 2.7 g AA equivalent/kg liveweight intraruminally. It was observed that all three types of AA administered increased the rumen and blood plasma AA concentrations to a desirable level with the maximum concentrations in both sites occurring during 1 hr after administration, indicating that the rumen could be the main site of absorption. The area under the concentration vs. time curve (AUC), area under the curve corrected for baseline (AUCB) and maximum concentration (MAX) of AA in both rumen fluid and blood plasma were not significantly different between the three formulations of AA, indicating that all three were degraded at a similar rate in the rumen and that their bioavailability was similar. Rumen pH decreased from approximately 7.0 to 5.0 units within one hour of administering each compound, increased to pH 6.0 after 4 hours and then progressively increased to approximately 7.0 units after 22 hours. There were no significant differences in AUC, AUCB, MAX or rumen pH between the three time periods, confirming that the experimental procedures used gave repeatable results. 3. Due to low rumen pH levels (5.0) experienced in Experiment 3, Experiment 4 was conducted to investigate the rumen buffering effect after dosing with AA along with sodium bicarbonate (NaHC03) to see whether the rumen pH levels could be maintained at 5.5 or above ( the lower end of the normal physiological range) during the course of the experiment. Seven rumen fistulated deer were used in a changeover design, in two periods. Four deer were intraruminally dosed with AA plus NaHCO3 (10:1 ratio) and the remaining 3 deer were dosed with only AA, the sequence was reversed in the second period. An amount of 2.7 g AA/kg liveweight as used in Experiment 3. It was possible to maintain the rumen pH above 5.5 in the group of deer that received AA plus NaHC03 but the ascorbic acid concentrations in both rumen fluid and blood plasma were lower than for the group of deer that received AA only. Including NaHCO3 increased rumen pH by approximately 1 unit during the first hour after dosing and by 0.7- 0.4 units thereafter. It was also observed that AUC and AUCB for rumen fluid were significantly lower for the AA plus NaHC03 group of deer than for AA group (P<0.05), indicating that increasing rumen pH had increased the rate of ruminal destruction of AA. The area under the concentration vs. time curve(AUC), AUCB and MAX of ascorbic acid in blood plasma were not statistically different between the two treatments (P>0.05), perhaps explained by NaHCO3 increasing rumen liquid FOR and hence the amount of AA absorbed post-ruminally. 4. Experiment 5 was conducted to study the differences in AA concentrations in the rumen, abomasum and blood plasma after administration of AA via rumen and also to observe the differences in AA concentrations in blood plasma after dosing with AA via abomasum. Three deer, fistulated in both the rumen and abomasum were administered intraruminally with AA (2.7 g/ kg liveweight) in trial 1. In trial 2, three deer were given AA 0.75 g/kg liveweight via the abomasum. Following intraluminal administration, it was observed that the AA concentration in the abomasum was much lower than that of rumen fluid. Mean AA concentration in blood plasma was very low when AA was given abomasally. Rumen adminstration of AA caused a rapid reduction in rumen pH (from 7.0 to 5.0 units) and a less rapid rise in abomasal pH (from 2.4 to 3.7 units). Abomasal administration of AA likewise caused an increase in abomasal pH but had no effect on rumen pH. 5. In Experiment 6, three deer fistulated in rumen and three deer fistulated in both the rumen and abomasum were used in two trials to measure the rumen fractional outflow rate (FOR) of liquid under normal conditions and after dosing with a large dose of AA into the rumen. In trial 1, all six deer were given Cr-EDTA (180ml, 2.77 mg Cr/ml water) via rumen fistula. In trial 2, all six deer were administered intraruminally the same dose of Cr-EDTA mixed with 2.7 g AA/kg liveweight. Rumen liquid FOR was low in the fasted deer (5.1 %/h) and was further reduced by administration of AA (3.5 %/hr; p<0.05), allowing more time for absorption from the rumen. It was calculated that 29% of the AA administered would flow out of the rumen between the time of dosing and infinity; however, as the half life of the solute marker in the rumen was approximately 20 hours, only half of the 29% (i.e. 14.5 of the dose) would flow out of the rumen in this time. The pH values in both rumen and abomasal fluid (AbF) of deer did not appreciably change with time when Cr-EDTA was given alone. The mean rumen pH values of deer used in trial 2, showed a rapid decline after administration of AA mixed with Cr-EDTA and this was followed by an increase in AbF pH as found in Experiment 5. Normal pH values were reached in rumen and AbF at 22 hours and 8 hours respectively after administration of AA intraruminally. 6. Overall it was concluded that the high AA single oral/intraruminal dose technique could be used to consistently increase the AUC, AUCB and MAX of AA concentrations in both rumen fluid and blood plasma. There was no significant difference between the three formulations of AA used (pure AA, EC and SC), probably due to similar rates of destruction of these 3 formulations by rumen bacteria, giving a similar bioavailability. Administration of AA into the rumen reduced the pH value during the initial period of one hour, which may have reduced the rate of AA destruction by the rumen microorganisms, as indicated by the reduction in AUCB when rumen pH was raised by including NaHCO3 with the AA administered. This is one of the reasons for suggesting that the main absorption site of AA occurred from the rumen and to a lesser extent from the abomasum and small intestines of deer. Other reasons include lower AA concentration in abomasal than rumen fluid, reduced liquid FOR from the rumen following the administration of a large dose of AA into the rumen and a calculated AA outflow of 14.5% of the dose during the first 20 h after administration. Methods for improving the efficiency of the single large dose AA technique are discussed and recommendations for future work are given.Item Evaluation of Lotus corniculatus for increasing the efficiency of growth in young deer : a thesis presented in partial fulfilment of the requirement for the degree of Masters of Applied Science, Animal Science option at Massey University(Massey University, 1997) Adu, Emmanuel KwadwoA grazing trial with lactating red deer (Cervus elaphus) hinds and their calves (EXPERIMENT 1), and an indoor digestion and calorimetric study (EXPERIMENT 2) were conducted at Massey University, New Zealand during 1996, to measure the feeding value of Lotus corniculatus compared to perennial ryegrass (Lolium perenne)/white clover (Trifolium repens) pasture for increasing the efficiency of growth in young deer. Half of the hinds and their calves were grazed on Lotus corniculatus and the other half were grazed on perennial ryegrass/white clover pasture during summer (Chapter Three) in a rotational grazing system. Half of the hinds in each group suckled pure red calves with the other half suckling hybrid (0.25 elk : 0.75 red deer) calves. The indoor experiments (Chapter Four) involved feeding one animal of a pair on either freshly cut perennial ryegrass or freshly cut Lotus corniculatus during autumn and spring, in metabolism cages and calorimetry chambers at maintenance (1M) and twice maintenance (2M) levels of energy intake. 1. EXPERIMENT 1 (CHAPTER THREE). Liveweight gains of hinds and their calves, weaning weight of calves and voluntary feed intake of hinds were measured on Lotus corniculatus or perennial ryegrass/white clover pasture during lactation in summer 1996. The percentage of dead matter in both the forage on offer and diet selected was lower in Lotus corniculatus than in perennial ryegrass/white clover pasture. The condensed tannin (CT) levels in Lotus corniculatus and perennial ryegrass/white clover pasture were 21 g and 1.6 g total CT/kg DM respectively. Organic matter digestibility (OMD) was higher for Lotus corniculatus than for perennial ryegrass/white clover pasture. Hinds grazing Lotus corniculatus had higher voluntary feed intake (VFI) and liveweight change than hinds grazing perennial ryegrass/white clover pasture, and liveweight gain and weaning weight of calves were greater on lotus. Liveweight gain and weaning weight of hybrid deer were superior to pure red deer calves, with pre-weaning liveweight gain of hybrid deer calves grazed on Lotus corniculatus exceeding 500 g/d for the first time. CT in Lotus corniculatus was more tightly bound in red deer oesophageal fistula (OF) extrusa samples than in comparable studies with sheep. 2. EXPERIMENT 2 (CHAPTER FOUR) Energy losses as methane, urine and heat were consistently lower when the deer were fed Lotus corniculatus (21 g total CT/kg DM) than perennial ryegrass (< 1 g total CT/kg DM), but faeces energy losses were similar for the two forages. The efficiency of utilisation of ME for growth (kg) was lower in autumn-grown than in spring-grown perennial ryegrass, and tended to be greater in autumn-grown Lotus corniculatus than autumn-grown perennial ryegrass. No significant differences existed in faecal N and urine N losses in deer fed the two forages, and N retention was similar in deer fed Lotus corniculatus and perennial ryegrass. Presence of CT-binding salivary proteins in deer but not in sheep is advanced as a reason for N retention not being greater on lotus. 3. The overall conclusion from this thesis was that as a summer feed during deer lactation, the feeding value of Lotus corniculatus is higher than that of perennial ryegrass/white clover pasture but essentially similar to that of other special purpose feeds developed for deer production such as chicory (Cichorium intybus) and red clover (Trifolium repens). The most cogent explanations for the higher performance in deer fed Lotus corniculatus is the higher VFI and the greater efficiency with which ingested energy was utilised. Because of the presence of salivary CT-binding proteins in deer, forages with higher CT concentrations are suggested for the realisation of the beneficial effects of forage CT on the efficiency of protein digestion in farmed deer. Two such forages are sulla (Hedysarum coronarium; 35-60 g CT/kg DM) and Lotus pedunculatus (50-100 g CT/kg DM). The incorporation of Lotus corniculatus into the pastoral agricultural system of NZ may be hindered by the slow establishment of the plant, and by the special management system required. It may be better suited agronomically to warm low to medium fertility hill country conditions, such as found in East Coast areas, where competition from other plant species is less.Item Methane emissions from farmed red deer : a thesis in partial fulfilment of the requirements for the degree of Master of Science in Animal Science at Massey University, Palmerston North(Massey University, 2004) Swainson, Natasha MadeleineMethane (CH4) is one of the end products of fermentation of ingested feed by the microbial population residing in the foregut of ruminants. It represents a potential loss of 2-12% of gross energy consumed, and is a potent greenhouse gas. The objective of this study was to firstly measure methane emissions for the first time using the sulfur hexafluoride tracer technique in red deer (Cervus elahus) grazing ryegrass-based pasture (Lolium perenne) and secondly, to compare methane emissions of deer grazing chicory (Cichorium intybus) and plantain (Plantago lanceolata) with those grazing ryegrass-based pasture. Methane production per day and per kg of dry matter intake (DMI) was measured using the sulfur hexafluoride tracer technique coupled the with η-alkane technique for feed intake estimation in 25 red deer grazing ryegrass-based pasture, chicory or plantain in March and May of 2003. Methane production per unit DMI obtained in this study (37.8 g / kg DMI) was approximately 75-80% greater than values used in the New Zealand National Greenhouse Gas Inventory for dairy cows and sheep, and estimated for deer grazing ryegrass-based pastures. Deer grazing chicory and plantain in March exhibited lower methane emissions per kg DMI compared with ryegrass-based pasture. However, in May methane emissions per kg of DMI from plantain was similar to pasture, which were both higher compared with chicory. The variability and accuracy of results obtained for estimated DMI using the alkane technique was questioned, and a lack of published information regarding methane production by red deer provided few possible explanations for the apparently high methane emissions. This prompted the initiation of an indoor study where DMI could be accurately measured concurrently with methane production using 12 animals from the grazing study. Mean methane production per kg DMI of 12 mature hinds housed individually indoors in metabolism cages and fed fresh ryegrass-based pasture in August 2003 was 22.5 g CH4/kg DMI. This figure was similar to published results obtained from sheep and cattle on similar diets and was 42% lower than the grazing study in autumn. This latter result emphasises the importance of obtaining accurate individual DMI measurements with which to express methane emissions per unit feed intake. Estimated dry matter intakes using the double n-alkane technique have not previously been validated against actual intakes for red deer, or for deer fed fresh forages. Therefore, the third experiment attempted to validate the use of this technique with rumen-fistulated, castrated red deer stags housed indoors and fed either fresh ryegrass-based pasture or plantain, while concurrently measuring methane production. Indirect estimation of DMI using the double n-alkane technique underestimated actual DMI of pasture by 23.5% and overestimated actual DMI of plantain by 13.9%. These results indicate that the estimation of DMI by the double n-alkane technique was possibly not valid for comparisons between treatments, and across experiments or animal species. The impact on methane emissions of the inaccurate estimation of DMI by the double n-technique resulted in methane production from deer fed pasture being overestimated by 11.0 g CH4/kg DMI and an underestimation of methane production of 4.8 g CH4/kg DMI for deer fed plantain. Findings of this thesis suggest that the measurement of methane from grazing and/or forage-fed animals should be conducted under conditions where DMI can be measured accurately, otherwise comparisons of methane production across treatments, experiments or species may be invalid. The latter two studies indicate that methane production of forage-fed red deer is similar to published values for sheep and cattle. However, this should be confirmed by direct comparisons where all species are fed the same diet, methane measurements are conducted over the same time period using identical methods, and feed intake can be accurately determined.