scholarly journals Effects of early castration on carcass composition, yield and quality characteristics of meat from young reindeer (Rangifer tarandus tarandus) bulls and steers

Rangifer ◽  
2008 ◽  
Vol 28 (1) ◽  
pp. 1 ◽  
Author(s):  
Eva Wiklund ◽  
Greg Finstad ◽  
Suzanne Worker ◽  
Peter J. Bechtel
Keyword(s):  
Rangifer Tarandus ◽  
Fat Content ◽  
Carcass Composition ◽  
Control Treatment ◽  
Control Group ◽  
Ph Values ◽  
Yield And Quality ◽  
Trained Panel ◽  
Sensory Attribute ◽  
Glycogen Stores

Thirty male reindeer; n=16 bulls (control treatment) and n=14 steers (castrated males) were used to evaluate the effects of early castration on carcass yield and meat quality attributes. The reindeer were castrated at 2 and 13 months of age, and then slaughtered at 2 and 3 years of age. Live weights and carcass weights were significantly highest in the 3 year old bulls and steers. Dressing percentage did not differ between the 2 and 3 year old reindeer steers castrated at 2 months; however these values were higher than for 2 year old steers castrated at 13 months. Meat ultimate pH values (measured in the striploin; LD) were significantly highest in 2 year old steers castrated at 13 months and their corresponding control group of 2 year old bulls, indicating low muscle glycogen stores at slaughter. Castration had an effect on fat content with 3 year old steers having a higher fat content than bulls. No significant differences were found in any sensory attribute when the trained panel compared the meat from 2 year old reindeer bulls and steers. Abstract in Swedish / Sammanfattning:Effekter av tidig kastrering på slaktkroppssammansättning, styckningsutbyte och köttkvalitet hos unga renarTrettio hanrenar; n=16 tjurar (kontrolldjur) och n=14 kastrater (härkar) ingick i denna studie för att utvärdera effekterna av tidig kastrering på slaktkroppssammansättning och köttkvalitetsparametrar. Renarna kastrerades vid 2 respektive 13 månaders ålder och slaktades sedan när de var antingen 2 eller 3 år gamla. Levandevikt och slaktkroppsvikt var högst för 3 år gamla tjurar och härkar. Slaktutbytet skiljde sig inte mellan 2 och 3 år gamla härkar som kastrerats vid 2 månaders ålder, men deras slaktutbyte var högre än för de 2-åriga härkarna som kastrerats vid 13 månaders ålder. Köttets pH-värde (mätt i ytterfilén) var signifikant högst hos de 2-åriga härkarna som kastrerats vid 13 månaders ålder och deras tillhörande kontrollgrupp av 2-åriga tjurar, vilket tydde på låga nivåer av muskelglykogen vid slakt. Kastrering hade en signifikant effekt på fettinnehållet i slaktkropparna hos de 3-åriga renarna, med de högsta fetthalterna hos härkarna. Inga skillnader i ätkvalitet rapporterades när kött från 2-åriga rentjurar och härkar jämfördes.

scholarly journals Influence of production system, age an sex on carcass parameters and some biochemical meat quality characteristics of reindeer (Rangifer tarandus tarandus L.)

Rangifer ◽  
2005 ◽  
Vol 25 (2) ◽  
pp. 85-96 ◽  
Author(s):  
Sabine Sampels ◽  
Jana Pickova ◽  
Eva Wiklund
Keyword(s):  
Lipid Class ◽  
Animal Studies ◽  
Rangifer Tarandus ◽  
Fat Content ◽  
Carcass Composition ◽  
Adult Males ◽  
Lipid Class Composition ◽  
Class Composition ◽  
Significant Difference ◽  
Carcass Parameters

Carcass composition in reindeer is affected by feed intake and the age and sex of the animal. Studies have also shown that age, sex, carcass trim fat content and total intramuscular fat content (IMF) influence lipid class composition. The aim of this study was to compare lipid class composition and IMF in relation to carcass weight, conformation and trim fat content, and to investigate how these parameters are affected by age, sex and different feed sources. Five groups of reindeer were studied. Two groups of calves were fed two grain-based pelleted feeds with different lipid compositions for approximately two months before slaughter. One of these groups was fed with conventional pellets, and the other with pellets enriched with linseed cake to increase the amount of n-3 fatty acids in the diet. Three groups of grazing reindeer were also included in the study, consisting of adult males, adult females or calves. Reindeer calves fed pellets had higher slaughter weights, higher trim fat content and better carcass conformation scores compared to the grazing calves. However, there was no significant difference in IMF between pellet-fed and grazing calves. Adult female reindeer had the highest and grazing calves the lowest slaughter weights, trim fat and IMF. There was no difference in lipid class composition in meat from calves fed with the two pelleted feeds, whereas grazing calves had a higher amount of phospholipids. Squalene was identified and quantified as a component of intramuscular lipids in reindeer meat. Effekt av produktionssystem, ålder och kön på slaktkroppskvalitet och några biokemiska egenskaper hos renköttAbstract in Swedish / Sammandrag: Slaktkroppssammansättningen hos renar påverkas av både foderintag, fodersammansättning och djurens ålder och kön. Tidigare har vi visat att renens kön, ålder, mängden intramuskulärt fett (IMF) och putsfett på slaktkroppen påverkar sammansättningen av lipidklasser. Syftet med denna studie var att jämföra lipidklassammansättningen och IMF i relation till slaktkroppens vikt, form och mängden putsfett och att undersöka hur dessa parametrar påverkas av renarnas kön, ålder och olika typer av foder (bete och pellets). Fem grupper renar ingick i studien (totalt 38 djur). Två grupper kalvar utfodrades med två sorters pellets med olika fettsammansättning under två månader före slakt. Den ena gruppen fick normala pellets (CPD) (Renfor Bas) medan den andra gruppen fick pellets som hade en tillsats av linfrökaka (LPD) för att öka mängden n-3 fettsyror i fodret. Dessutom ingick tre grupper betesdjur i studien: vajor, sarvar och kalvar. Utfodring med pellets gav slaktkroppar med bättre klassning, högre slaktvikter och mer putsfett jämfört med slaktkroppar från betande kalvar. Vajorna hade de högsta och betande kalvar de lägsta slaktvikterna, minst putsfett och lägst halt av IMF. Utfodringen med pellets gav ingen signifikant skillnad i IMF mellan betande och utfodrade renkalvar. Vi fann ingen skillnad i lipidklassammansättning mellan de två utfodrade kalvgrupperna, men köttet från de betande kalvarna hade en högre halt av fosfolipider. Vi kunde också identifiera och kvantifiera squalen som en komponent i intramuskulärt fett i renkött.

Does carcass suspension technique influence reindeer (Rangifer tarandus tarandus) meat quality attributes?

2012 ◽  
Vol 52 (8) ◽  
pp. 731 ◽  
Author(s):  
E. Wiklund ◽  
G. Finstad ◽  
G. Aguiar ◽  
P. J. Bechtel
Keyword(s):  
Achilles Tendon ◽  
Shear Force ◽  
Rangifer Tarandus ◽  
Control Treatment ◽  
Meat Tenderness ◽  
Triceps Brachii ◽  
Obturator Foramen ◽  
Trained Panel ◽  
Meat Colour ◽  
Meat Samples

In total, eight reindeer steers (ages 3–6 years old) were used in the study to evaluate the effects of carcass suspension technique on meat tenderness, colour and water-holding capacity (WHC). Carcasses were split along the spine and sides were randomly allocated to pelvic suspension (hung using a butcher hook through the obturator foramen) or normal Achilles tendon suspension (control treatment). From all 16 carcass halves, meat samples were collected from the loin (M. longissimus), inside (M. semimembranosus) and shoulder (M. triceps brachii) for sensory evaluation and measurements of shear force (tenderness). Loin samples were also evaluated for meat colour at 1 day after slaughter and for purge (WHC) after vacuum-packaged chilled storage (+2°C) for 1, 2 and 3 weeks. No significant effects of carcass suspension technique were found for reindeer meat colour and WHC (purge). Shear force values for loin samples from pelvic-suspended carcasses were significantly (P = 0.001) lower than those from Achilles tendon-suspended carcasses, and there was a similar trend for inside samples, although this was not significant (P = 0.06). There was no effect of carcass suspension technique for shear force values of the shoulder samples. The trained panel judged loin and inside samples from pelvic-suspended carcasses to be more tender (P ≤ 0.001) while no effect of carcass suspension technique on tenderness was found in the shoulder samples. Juiciness was not affected by carcass suspension. The present study demonstrated that pelvic suspension improved tenderness in the most valuable cuts from the reindeer carcass (loin and inside).

scholarly journals The effects of pre-slaughter selection of reindeer bulls (Rangifer tarandus tarandus L.) on technological and sensory meat quality, blood metabolites and abomasal lesions

Rangifer ◽  
1997 ◽  
Vol 17 (2) ◽  
pp. 65 ◽  
Author(s):  
E. Wiklund ◽  
G. Malmfors ◽  
K. Lundström
Keyword(s):  
Meat Quality ◽  
Muscle Glycogen ◽  
Rangifer Tarandus ◽  
Glycogen Content ◽  
Acute Stress ◽  
Selection Procedure ◽  
High Plasma ◽  
Blood Metabolites ◽  
Control Group ◽  
Ph Values

Thirty reindeer bulls (age 1 1/2 years) were subjected to different pre-slaughter treatments to study the effects on ultimate pH values, muscle glycogen content, blood metabolites and abomasal lesions. Gathering and herding into a grazing corral were followed by various selection procedures. Before starting these, a control group of 10 reindeer were captured by lasso and slaughtered outside the grazing corral. Ten reindeer were then selected by hand from a small group of animals (100-150 head) in a small selection corral. Another 10 reindeer were selected from a large herd of about 1000-2000 animals, by the traditional technique of using a lasso. During a 6-hour selection, animals were captured and slaughtered after 1.5 hours (n = 2), 3-5 hours (n = 2), 5 hours (n = 3) and 6 hours (n=3) respectively. The results showed the technique of using a lasso to be stressful and glycogen-depleting, as the two lasso captured groups (the control group and the reindeer exposed to the protracted lasso selection) had the highest ultimate pH values and lowest muscle glycogen values measured. By contrast, the selection procedure where reindeer were captured by hand, was not found to be detrimental to glycogen content and ultimate pH values. Nevertheless, both selection techniques expose the reindeer to acute stress during the capture and manual restraint, which in the present study was reflected in high plasma Cortisol values in all treatment groups. The frequency of abomasal lesions was highest in the group of reindeer subjected to the prolonged selection procedure. No connection between technological and sensory meat quality was found in this study. The technique of selecting animals by hand ought to be further developed so that existing practical problems can be solved. The technique could then be recommended for wider use.

The effectiveness of use RUSMA additive in the rations of lactating cows

2020 ◽  
pp. 28-37
Author(s):  
S. Sukhanova ◽  
N. Pozdnyakova ◽  
F. Yaroslavtsev
Keyword(s):  
Milk Fat ◽  
Raw Materials ◽  
Fat Content ◽  
Feed Additives ◽  
Control Group ◽  
New Mineral ◽  
Milk Productivity ◽  
Black And White ◽  
Lactating Cows ◽  
Experimental Group

The results of researches on the development of new mineral feed additives based on raw materials produced by Uralchem and the study of the eff ectiveness of their use in the rations of lactating cows have been presented in the article. The experiment has been carried out in the conditions of LLC “PF Barabinskoe” in the Dalmatovsky area in the Kurgan region where 3 groups of lactating cows of Black-and-White breed have been formed. Animals in the control group have been received the ration adopted in the farm, the 1st experimental group with the additive RusMA No. 1 at a dose of 150 g, the 2nd experimental group– with the additive RusMA No. 2 at the dose of 350 g. The use of experimental mineral additives in feeding lactating cows allowed us to increase their milk productivity and profi tability of production. At the same time, the best eff ectiveness was shown by the additive RusMA No. 2 at the dose of 350 g/head/day. The use of RusMA additives during the experiment period (105 days) allowed to increase the milk productivity of cows in the 1st experimental group by 6,03 % and in the 2nd experimental group by 8,24 %. Taking into account the fat content in milk, this diff erence was 6,31 and 8,53 %, respectively. The energy value of milk from cows of the experimental groups was higher compared to the control group by 2,45 and 1,76 %, respectively. According to the content of dry matter in milk, cows of the 2nd experimental group exceeded the control and 1st experimental group by 0,39 and 0,12 abs.%, respectively. The maximum milk fat content has been observed in the milk of cows of the 1st experimental group by 0,03 and 0,01 abs.% more than in the control and 2nd experimental groups, respectively. In terms of protein content, the cows of the 2nd experimental group signifi cantly exceeded the control group by 0,10 abs.% and the 1st experimental by 0,04 abs.%. The content of milk sugar in the 2nd experimental group was higher than in the control by 0,30 abs.% and compared to the 1st experimental by 0,11 %. Signifi cantly more calcium and phosphorus were contained in the milk of cows of the 2nd experimental group by 4,58 % (Р ≤ 0,001) and 2,86 % (Р ≤ 0,05), compared with the control group. The expenditures of feed in the EFU for the production of 1 kg of milk in animals of the 2nd experimental group was less by 5,13 % than in control cows and by 2,63 % compared to the 1st experimental group. The prime cost of 1 centner of milk was lower in the 2nd experimental group by 3,94 %, in the 1st experimental group by 2,65 % compared to the control group. The level of profi tability of milk production in the 2nd experimental group was higher by 9,0 and 1,0 abs.% in comparison with the control and 1st experimental groups, respectively.

Mechanism Involved in Fortification by Berberine in CDDP-Induced Nephrotoxicity

2020 ◽  
Vol 13 (4) ◽  
pp. 342-352 ◽  
Author(s):  
Vipin K. Verma ◽  
Salma Malik ◽  
Ekta Mutneja ◽  
Anil K. Sahu ◽  
Kumari Rupashi ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Renal Tissue ◽  
Isoquinoline Alkaloid ◽  
Experimental Models ◽  
Beclin 1 ◽  
Control Treatment ◽  
Control Group ◽  
Treatment Groups ◽  
Single Intraperitoneal Injection ◽  
Male Wistar Rats

Background: The activation of Nrf2/HO-1 pathway has been shown to protect against cisplatin- induced nephrotoxicity by reducing oxidative stress. Berberine (Ber), an isoquinoline alkaloid, has demonstrated antioxidant, anti-inflammatory and anti-apoptotic activities in various experimental models. Aim: To check the effect of Ber on cisplatin-induced nephrotoxicity and to explore the involved mechanism. Methods: Adult male Wistar rats were divided into 6 groups: Normal, cisplatin-control, treatment groups and per se group. Normal saline and Ber (20, 40 and 80 mg/kg; p.o.) was administered to rats for 10 days. A single intraperitoneal injection of cisplatin (8 mg/kg) was injected on 7th day to induced nephrotoxicity. On 10th day, rats were sacrificed, the kidney was removed and stored for the estimation of various parameters. Results: As compared to cisplatin-control group, Ber pretreatment improved renal function system and preserved renal architecture. It also diminished oxidative stress by upregulating the expression of Nrf2/HO-1 proteins. In addition, Ber attenuated the cisplatin mediated inflammation and apoptosis. Furthermore, it also reduced the phosphorylation of p38/JNK and PARP/Beclin-1 expression in the kidney. Conclusion: Ber attenuated renal injury by activating Nrf2/HO-1 and inhibiting JNK/p38MAPKs/ PARP/Beclin-1 expression which prevented oxidative stress, inflammation, apoptosis and autophagy in renal tissue.

Glycine and L-Arginine supplementation ameliorates gastro-duodenal toxicity in a rat model of NSAID (Diclofenac)-gastroenteropathy via inhibition of oxidative stress

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Akinleye Stephen Akinrinde ◽  
Halimot Olawalarami Hameed
Keyword(s):  
Oxidative Stress ◽  
Total Protein ◽  
Therapeutic Index ◽  
Control Treatment ◽  
Control Group ◽  
Protective Effects ◽  
Serum Total Protein ◽  
Significant Amelioration ◽  
Group A ◽  
Group B

Abstract Objectives This study examined the possible protective roles of exogenous glycine (Gly) and L-Arginine (l-Arg) against Diclofenac (DIC)-induced gastro-duodenal damage in rats. Methods Rats were divided into Group A (control), Group B (DIC group) and Groups C–F which were pre-treated for five days with Gly1 (250 mg/kg), Gly2 (500 mg/kg), l-Arg1 (200 mg/kg) and l-Arg2 (400 mg/kg), respectively, before co-treatment with DIC for another three days. Hematological, biochemical and histopathological analyses were then carried out. Results DIC produced significant (p<0.05) reduction in PCV (13.82%), Hb (46.58%), RBC (30.53%), serum total protein (32.72%), albumin (28.44%) and globulin (38.01%) along with significant (p<0.05) elevation of serum MPO activity (83.30%), when compared with control. In addition, DIC increased gastric H2O2 and MDA levels by 33.93 and 48.59%, respectively, while the duodenal levels of the same parameters increased by 19.43 and 85.56%, respectively. Moreover, SOD, GPx and GST activities in the DIC group were significantly (p<0.05) reduced in the stomach (21.12, 24.35 and 51.28%, respectively) and duodenum (30.59, 16.35 and 37.90%, respectively), compared to control. Treatment with Gly and l-Arg resulted in significant amelioration of the DIC-induced alterations although l-Arg produced better amelioration of RBC (29.78%), total protein (10.12%), albumin (9.93%) and MPO (65.01%), compared to the DIC group. The protective effects of both amino acids against oxidative stress parameters and histological lesions were largely similar. Conclusions The data from this study suggest that Gly or l-Arg prevented DIC-induced gastro-duodenal toxicity and might, therefore be useful in improving the therapeutic index of DIC.

scholarly journals Effects of a Trans-Galactooligosaccharide on Minerals Content of Common Carp (Cyprinus carpio L.) Tissues

2021 ◽  
Author(s):  
Ewa Ziółkowska ◽  
Joanna Bogucka ◽  
Jan Mazurkiewicz ◽  
Mateusz Rawski ◽  
Szymon Różański ◽  
...  
Keyword(s):  
Common Carp ◽  
Cyprinus Carpio ◽  
Control Diet ◽  
Colorimetric Method ◽  
Bifidobacterium Bifidum ◽  
Feed Additives ◽  
Control Treatment ◽  
Control Group ◽  
Whole Cells ◽  
Freeze Dried

AbstractCommon carp (Cyprinus carpio L.) is a dominant fish species in aquaculture, and as it is a stomachless species, absorption and digestion of nutrients take place in the intestine. The aim of the study was to evaluate the effects of a prebiotic on the content of selected minerals found in the meat, gills, and skeleton of common carp. The research applied trans-galactooligosaccharide (GOS) prebiotic produced by enzymatic transgalactosylation of milk lactose by whole cells of Bifidobacterium bifidum. The following diets have been applied: control diet without feed additives (C), diet 2 (B1) with 1% of GOS, and diet 3 (B2) with 2% of GOS. In the freeze-dried samples, concentrations of the analyzed metals were determined using atomic absorption spectroscopy (AAS). The content of phosphorus was determined using colorimetric method. The analyses confirmed that the highest level of Mg was detected in the skeleton of fish fed with 1% GOS (2.51 g kg−1) and was significantly higher compared the control treatment (2.11 g kg−1) (P < 0.05). Zn content in fish meat fed with 1% GOS (35.41 mg kg−1) was significantly higher (P < 0.05) than in the control group (24.59 mg kg−1). The tissue that accumulated the greatest amount of Zn was the gills. GOS had a positive effect on Fe accumulation in the meat, gills, and skeleton. It has been concluded that supplementation of feed with 2% GOS significantly influenced the positive correlations between Mg and P in the meat and skeleton, Fe–Ca correlation in gills, and Fe–Zn correlation in the skeleton.

scholarly journals Reoperations Following Lumbar Discectomy Are Associated With Worse Clinical Outcomes and Greater Socioeconomic Burden 3 Years After the Primary Procedure

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Claudius Thomé ◽  
Ali Araghi ◽  
Jason Inzana ◽  
Jonathan Stieber ◽  
Joshua M Ammerman
Keyword(s):  
Back Pain ◽  
Clinical Outcomes ◽  
Lumbar Discectomy ◽  
Control Treatment ◽  
Control Group ◽  
Closure Device ◽  
Number Of Patients ◽  
Patient Reported ◽  
Socioeconomic Burden ◽  
Index Level

Abstract INTRODUCTION Lumbar discectomy patients with large annular defects are at significantly greater risk for symptom recurrence and revision. Previous studies suggest that outcomes following revision surgery are less positive than outcomes from primary discectomy. This analysis aimed to assess the clinical and socioeconomic outcomes associated with postdiscectomy reoperations and the utility of a bone-anchored annular closure device (ACD) for avoiding reoperations. METHODS This study was a retrospective analysis of a prospective randomized controlled trial (RCT). Lumbar discectomy patients with large (>6 mm) annular defects were treated with discectomy alone (Control; n = 278) or discectomy with an ACD (n = 272). Patient-reported outcomes included visual analog scale (VAS) for ipsilateral leg or back pain and Oswestry Disability Index (ODI). At 3 yr, clinical outcomes were available for 75% of the patients. Comparisons of outcomes were made between reoperated (n = 64) and nonreoperated (n = 351) patients, regardless of ACD or Control treatment, at 3 yr following the primary surgery. RESULTS Reoperated patients had significantly worse scores for ODI (24 ± 19 vs 11 ± 13; P < .0001), VAS leg pain (28 ± 30 vs 12 ± 19; P < .0001), and VAS back pain (36 ± 31 vs 17 ± 21; P < .0001). Significantly more nonreoperated patients were working at 3 yr (97% vs 84%; P < .001). Based on Kaplan-Meier analysis, the proportion of subjects experiencing at least 1 index-level reoperation in 3 yr was 11% in the ACD group and 19% in the Control group (P = .007). CONCLUSION Index-level reoperations following lumbar discectomy are associated with worse outcomes and greater socioeconomic burden in patients with large annular defects (>6 mm). These findings are consistent with reports from large registry analyses, including the Spine Patient Outcomes Research Trial (SPORT) and the Swedish National Spine Registry (Swespine). The ACD reduced the number of patients experiencing index-level reoperation by 43%.

Statistical methods for unidirectional switch designs: Past, present, and future

2017 ◽  
Vol 27 (9) ◽  
pp. 2872-2882 ◽  
Author(s):  
Zhuozhao Zhan ◽  
Geertruida H de Bock ◽  
Edwin R van den Heuvel
Keyword(s):  
Statistical Methods ◽  
Large Scale ◽  
Sample Size Calculation ◽  
Complex Interventions ◽  
New Drugs ◽  
Control Treatment ◽  
Future Research ◽  
Control Group ◽  
Unified Framework ◽  
New Treatment

Clinical trials may apply or use a sequential introduction of a new treatment to determine its efficacy or effectiveness with respect to a control treatment. The reasons for choosing a particular switch design have different origins. For instance, they may be implemented for ethical or logistic reasons or for studying disease-modifying effects. Large-scale pragmatic trials with complex interventions often use stepped wedge designs (SWDs), where all participants start at the control group, and during the trial, the control treatment is switched to the new intervention at different moments. They typically use cross-sectional data and cluster randomization. On the other hand, new drugs for inhibition of cognitive decline in Alzheimer’s or Parkinson’s disease typically use delayed start designs (DSDs). Here, participants start in a parallel group design and at a certain moment in the trial, (part of) the control group switches to the new treatment. The studies are longitudinal in nature, and individuals are being randomized. Statistical methods for these unidirectional switch designs (USD) are quite complex and incomparable, and they have been developed by various authors under different terminologies, model specifications, and assumptions. This imposes unnecessary barriers for researchers to compare results or choose the most appropriate method for their own needs. This paper provides an overview of past and current statistical developments for the USDs (SWD and DSD). All designs are formulated in a unified framework of treatment patterns to make comparisons between switch designs easier. The focus is primarily on statistical models, methods of estimation, sample size calculation, and optimal designs for estimation of the treatment effect. Other relevant open issues are being discussed as well to provide suggestions for future research in USDs.

The response of pygmy bluetongue lizards to simulated grazing in the field during three drought years

2012 ◽  
Vol 39 (6) ◽  
pp. 540 ◽  
Author(s):  
Melissa Pettigrew ◽  
C. Michael Bull
Keyword(s):  
Prey Availability ◽  
Careful Consideration ◽  
Grazing Management ◽  
Control Treatment ◽  
Ground Vegetation ◽  
Control Group ◽  
Drought Period ◽  
Before And After ◽  
Simulated Grazing ◽  
Complex Relationships

Context Grazing by domestic stock can directly influence and shape the functions of an ecosystem. Most remaining remnant native grasslands in Australia are under some form of grazing management, with some possible adverse impacts for endemic grassland biota. For the endangered pygmy bluetongue lizard (Tiliqua adelaidensis), grazing of its remnant native grassland habitat has been seen as a potential conservation threat. Aim We aimed to investigate whether lizards altered their basking and foraging behaviour as a response to simulated grazing of the grassland habitat surrounding their burrows. Methods We used field manipulations over 3 years event by manually removing above-ground vegetation in 1 m2 around occupied lizard burrows, to simulate intense grazing events. We video-recorded lizard responses to these manipulations. We filmed lizards before and after the simulated grazing event and monitored basking and foraging response. We also simultaneously filmed a control group of lizards that were not exposed to a simulated grazing event. Key results Although overall time spent basking did not differ between treatment and control groups, the lizards spent more of their basking time completely emerged (bold basking) in the grazing treatment, suggesting they changed behaviour after simulated grazing. Perhaps they were more confident of evading predators that they could more clearly see approaching. In one season lizards made more attempts to catch prey in the grazed treatment than in a control treatment following the treatment, suggesting that grazing might enhance visibility for the ambush predation method that these lizards use. Conclusions The results suggest that grazing may produce some benefits for lizards already established in burrows. This contrasts with some previous results and suggests that management of grazing regimes requires careful consideration of the conditions currently prevalent. In this case, the study was conducted during a drought period, and different results might have emerged in higher rainfall years. Implications Grazing management for lizard conservation requires detailed understanding of the complex relationships among lizard behaviour, vegetation cover and invertebrate prey availability.

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