Simulated preslaughter holding and isolation effects on stress responses and live weight shrinkage in meat goats

The objective of this experiment was to determine the effects of preslaughter isolation and feed withdrawal duration on physiological responses and shrinkage in goats. A total of 84 Spanish does (36 mo of age, average weight 35 kg) were individually weighed and scored for excitability before two replicate (day) trials. The does were feed-deprived (FD) or fed (F) in holding pens (treatment, TRT) for either 0, 7, 14, or 21 h (TIME). At the end of the holding periods, FD and F does were blood-sampled (n = 6 does/treatment/time/replicate) and weighed again to assess physiological responses and shrinkage, respectively. Individual does from each pen were blood-sampled again after imposing one of three handling post-treatments: a 15-min isolation with no visual contact with other does (I); a 15-min isolation with visual contact (IV); or no isolation (C, control). Plasma cortisol concentrations were higher at 0 h than at other holding time periods (P < 0.01). Plasma triiodothyronine, thyroxine, and leptin concentrations, and differential leukocyte counts were not influenced by any of the factors. The rate of decline in glucose concentrations over TIME was greater in FD than in F group (TRT x TIME, P < 0.05). The overall plasma creatine kinase activity peaked at 7 h before reaching a lower level at 14- and 21-h holding (P < 0.05). Plasma urea nitrogen concentrations were higher at 0- and 21-h than at 7- and 14-h holding (P < 0.01). Plasma nonesterified FA concentrations in the FD group remained at an elevated level during holding, but in the F group the levels decreased at 7 h and remained at that level (TRT x TIME, P < 0.01). Excitability scores did not have any effect on the variables measured. Shrinkage increased with longer holding time, but more prominently in the FD group (TRT x TIME, P < 0.01). Plasma cortisol concentrations were greater in I and IV groups than in the C group (P < 0.01). The novelty of environment during preslaughter holding, and social isolation may be more potent stressors than feed deprivation in goats, although shrinkage may increase with increasing feed-withdrawal times.     

Preliminary results on the effects of diazepam on physiological responses to transport in male goats

Diazepam given i.v. to goats at 0.2 mg/kg body wt suppressed transport-induced hypercortisolaemia, hyperglycaemia, tachypnoea and tachycardia. A rebound increase in cortisol concentrations, respiratory and heart rates was seen during the recovery period after sedation.     

Preslaughter diet management in sheep and goats:effects on physiological responses and microbial loads on skin and carcass

Sixteen crossbred buck goats(Kiko x Spanish;BW = 32.8 kg) and wether sheep(Dorset x Suffolk;BW = 39.9 kg) were used to determine the effect of preslaughter diet and feed deprivation time(FDT) on physiological responses and microbial loads on skin and carcasses.Experimental animals were fed either a concentrate(CD) or a hay diet(HD)for 4 d and then deprived of feed for either 12-h or 24-h before slaughter.Blood samples were collected for plasma Cortisol and blood metabolite analyses.Longisimus muscle(LM) pH was measured.Skin and carcass swabs were obtained to assess microbial loads.Plasma creatine kinase activity(863.9 and 571.7 ± 95.21 IU) and non-esterified fatty acid concentrations(1,056.1 and 589.8 + 105.01 mEq/L) were different(P 0.05) between sheep and goats.Species and diet treatments had significant effects on the ultimate pH of LM.Pre-holding total coliform(TCC) and aerobic plate counts(APC) of skin were significantly different between species.Goats had lower(P 0.05) TCC(2.1 vs.3.0 log_(10) CFU/cm~2) and APC(8.2 vs.8.5 log_(10) CFU/cm~2) counts in the skin compared to sheep.Preslaughter skin E.coli counts and TCC were different(P 0.05) between species.Goats had lower(P 0.05) counts of E.coli(2.2 vs.2.9 log_(10) CFU/cm~2) and TCC(2.3 vs.3.0 log_(10) CFU/cm~2) in the skin compared with those in sheep.Diet,species,and FDT had no effect(P 0.05) on E.coli and TCC in carcass swab samples.The APC of carcass swab samples were only affected(P 0.05) by the FDT.The results indicated that preslaughter dietary management had no significant changes on hormone and blood metabolite concentrations and sheep might be more prone for fecal contamination than goats in the holding pens at abattoir.     

Preslaughter diet management in sheep and goats: effects on physiological responses and microbial loads on skin and carcass

Sixteen crossbred buck goats (Kiko x Spanish; BW = 32.8 kg) and wether sheep (Dorset x Suffolk; BW = 39.9 kg) were used to determine the effect of preslaughter diet and feed deprivation time (FDT) on physiological responses and microbial loads on skin and carcasses. Experimental animals were fed either a concentrate (CD) or a hay diet (HD) for 4 d and then deprived of feed for either 12-h or 24-h before slaughter. Blood samples were collected for plasma cortisol and blood metabolite analyses. Longisimus muscle (LM) pH was measured. Skin and carcass swabs were obtained to assess microbial loads. Plasma creatine kinase activity (863.9 and 571.7 ± 95.21 IU) and non-esterified fatty acid concentrations (1,056.1 and 589.8 ± 105.01 mEq/L) were different (P < 0.05) between sheep and goats. Species and diet treatments had significant effects on the ultimate pH of LM. Pre-holding total coliform (TCC) and aerobic plate counts (APC) of skin were significantly different between species. Goats had lower (P < 0.05) TCC (2.1 vs. 3.0 log₁₀ CFU/cm²) and APC (8.2 vs. 8.5 log₁₀ CFU/cm²) counts in the skin compared to sheep. Preslaughter skin E. coli counts and TCC were different (P < 0.05) between species. Goats had lower (P < 0.05) counts of E. coli (2.2 vs. 2.9 log₁₀ CFU/cm²) and TCC (2.3 vs. 3.0 log₁₀ CFU/cm²) in the skin compared with those in sheep. Diet, species, and FDT had no effect (P > 0.05) on E. coli and TCC in carcass swab samples. The APC of carcass swab samples were only affected (P < 0.05) by the FDT. The results indicated that preslaughter dietary management had no significant changes on hormone and blood metabolite concentrations and sheep might be more prone for fecal contamination than goats in the holding pens at abattoir.     

热应激对山羊生理生化指标的影响

3只健康山羊置于人工热应激环境中(环境温度37.5～38.5℃),1小时后回到自然环境(24.5～26.5℃).试验前及试验开始后第15、60、180分钟,分别测定心率、呼吸频率、体温、红细胞数(RBC)、白细胞数(WBC)、血糖、血清谷草转氨酶(GOT)、谷丙转氨酶(GPT)、肌酸激酶(CK)、总蛋白(TP)、清蛋白(Alb)、尿素氮(BUN)含量.结果表明,热应激时,山羊的心率、呼吸频率、血糖含量均有一定程度的上升;CK在热应激中有明显的上升;WBC略有下降;RBC和血清中GOT、GPT、TP、BUN含量变化不显著.     

热应激对山羊生理生化指标的影响

３只健康山羊置于人工热激环境中（环境温度３７．５～３８．５℃）,１小时后回到自然环境（２４．５～２６．５℃）。试验前及试验开始后第１５、６０、１８０分钟,分别测定心率、呼吸频率、体温、红细胞数（ＲＢＣ）、白细胞数（ＷＢＣ）、血糖、血清谷草转氨酶（ＧＯＴ）、谷丙转氨酶（ＧＰＴ）、肌酸激酶（ＣＫ）、总蛋白（ＴＰ）、清蛋白（Ａｌｂ）、尿素氮（ＢＵＮ）含量。结果表明,热应激时,山羊的心率、呼吸频率、血糖含量均有一定程度的上升;ＣＫ在热应激中有明显的上升;ＷＢＣ略有下降;ＲＢＣ和血清中ＧＯＴ、ＧＰＴ、ＴＰ、ＢＵＮ含量变化不显著。     

The effect of live weight gain and live weight loss on body composition of merino wethers: chemical composition of the dissected components.

Chemical composition of the dissected side parts and dissected side was measured during live weight gain (LWG) and live weight loss (LWL) to determine effects on the chemical composition of the dissected side parts. Thirty-five Merino wethers had ad libitum access to the experimental diet (17.23% CP and 12.09 MJ/kg of DE) to grow from 23.0 to 33.0 kg live weight and then were fed to lose a total of 10 kg in three periods of 25 d each at the rate of 133 g/d. Groups of five animals were slaughtered at live weights of 23.0, 26.3, 29.6, and 33.0 kg during LWG and 29.6 kg (first period), 26.3 kg (second period), and 23.0 kg (third period) during LWL. The greater dissected side weight in LWL animals than in LWG animals at 23.0 kg of live weight was due to the significantly greater chemical fat (P < .05) in the LWL animals than in the LWG animals at 23.0 kg. There were no significant differences between treatments in the protein and water weights in the dissected side. The general increase in the chemical fat in the dissected side of the LWL animals was due to the significant increase in the chemical fat in the muscle (P < .01) and bone (P < .01, 23.0 and 26.3 kg and P < .05, 29.6 kg) at each common slaughter weight and subcutaneous fat (P < .05), intermuscular fat (P < .05) kidney and channel fat (P < .05), and total side fat (P < .01) at 23.0 kg.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of live weight gain and live weight loss on body composition of Merino wethers: dissected muscle, fat, and bone.

Sheep were slaughtered after live weight gain (LWG) and live weight loss (LWL) to evaluate the effect of different periods of normal and retarded growth on dissected carcass components. Thirty-five Merino wether sheep were allowed ad libitum access to the experimental diet of 80% alfalfa chaff and 20% cereal grain (17.23% CP and 18.10 MJ/kg of GE) to grow from 23.0 to 33.0 kg live weight and then fed to lose 10 kg at 133 g/d. Five animals were slaughtered at live weights of 23.0, 26.3, 29.6, and 33.0 kg during LWG and 29.6, 26.3, and 23.0 kg during LWL. Fleece-free empty BW was similar in both LWG and LWL animals at all common slaughter weights because of the lesser and greater weights of the alimentary tract contents and the fleece, respectively, in the LWL animals. Carcass weight or dissected side weight was greater in LWL animals at each common slaughter weight but significantly so (P less than .05) at the 23.0 kg live weight only. Total side muscle weight was similar in LWG and LWL animals at each common slaughter weight, but the proportion of muscle in the dissected side weight was lower (P less than .05) in LWL animals at 23.0 kg live weight. Total side fat, subcutaneous fat, intermuscular fat, and kidney and channel fat weights were all greater in LWL animals at each common slaughter weight, but significantly so (P less than .05) at the 23.0 kg live weight only. Total side bone weight was higher at both 26.3 kg (P less than .01) and 23.0 kg (P less than .05) in the LWL animals. Weight loss in young sheep mobilized more weight of muscle than fat from the carcass, whereas bone weight was constant.     

Social isolation of goats: significance of visual contact with conspecifics on behavioral and physiological responses

Social isolation can increase distress in goats, particularly when they cannot maintain visual contact with conspecifics. This experiment was conducted to determine the behavioral and physiological responses in goats during isolation with or without visual contact with conspecifics. Male Spanish goats (uncastrated, 8 mo old, average weight 29.4 ± 0.59 kg) were randomly assigned to a control (CO) group with no isolation or to one of four isolation treatment (TRT) pens (1.5 × 1.5 m) with: 1) open grill panels but with no visual contact with conspecifics (IO), 2) covered grill to prevent visual contact (IC), 3) open grill with visual contact (IV), or 4) covered grill with a 30 × 30 cm window to allow visual contact (IW), for 90 min of social isolation (n = 12 goats per TRT). Blood samples were collected at 0, 30, 60, and 90 min (Time) from isolated and control goats. The experiment was repeated 1 wk later using the same animals, with each goat being subjected to the same isolation TRT the second time to study the effect of prior exposure to isolation. Friedman’s two-way analysis of variance by Ranks test in SAS showed that the median frequency of vocalization (rank score) in goats was high in the IO group, low in the IV and IW groups, and intermediate in the IC group (P < 0.01). The vocalization rank score was also higher (P < 0.01) during the first 30 min of isolation in goats. The median frequency of visual contact was higher in the IW group than in the IV group (P < 0.01). The frequency of climbing behavior was high in the IC and IO groups, low in the IV group, and intermediate in the IW group (P < 0.01). Repeated measures analysis using general linear models procedures in SAS revealed that plasma cortisol and glucose concentrations tended (P < 0.1) to be the highest in the IO group than in CO, IC, IV, and IW groups. Cortisol levels were also higher (Time; P < 0.05) at 0 and 90 min compared with 30 and 60 min. Norepinephrine concentrations decreased (P < 0.05) with Time, and plasma nonesterified fatty acid (NEFA) levels were affected by TRT × Time interaction (P < 0.01). Overall, epinephrine, norepinephrine, glucose, and NEFA concentrations were lower (P < 0.01) and cortisol concentrations and lymphocyte counts were higher (P < 0.01) when goats were exposed to isolation the second time. The results showed that goats with no visual contact with conspecifics during social isolation had greater physiological stress responses and spent more time vocalizing or trying to escape the pen, which may indicate distress.     

Nutritionally induced body weight loss and ovarian quiescence in Shiba goats

Four female Shiba goats were used to determine the influence of body weight loss by dietary restriction on estrous cyclicity. The dietary restriction was started on the day following ovulation. The goats were fed hay cube and straw at an amount of 30% of energy requirement based on weekly body weight measurement. The ovaries were monitored daily by transrectal ultrasonography and blood samples were collected daily by jugular venipuncture for ovarian steroids analysis. After the start of food restriction, all animals lost body weight and entered ovarian quiescence. Intervals to the onset of ovarian quiescence tended to depend on the body weight of each animal at the start of food restriction. The mean concentration of progesterone during the mid-luteal phase (from 7 to 13 days after ovulation) in the last estrous cycle before ovarian quiescence was significantly lower than that in normal estrous cycle of the control period (19.7 +/- 2.8 vs 12.3 +/- 2.2 ng/ml, P<0.05), whereas there was no significant difference in the length of the luteal phase, determined as the period when corpora lutea existed and concentrations of progesterone were equal to or greater than 1 ng/ml (15.8 +/- 1.5 vs 15.0 +/- 2.8 days, P>0.1). A rise of estradiol concentration and follicular growth in the follicular phase following a decline of progesterone level after luteal regression tended to be suppressed at the onset of ovarian quiescence. It seems that the present results are consistent with previous findings that nutritionally induced body weight loss influences the secretion of ovarian steroids and eventually induces ovarian quiescence.     

Effect of postpartum live weight loss on reproductive functions in dairy cows

Postpartum loss of live weight in dairy cows and its association with reproductive functions were studied in a total of 84 (42 Ayrshire and 42 Friesian) cows. The cows were divided according to type of feed into 2 groups of equal size: a hay-urea group and a silage group. The duration of the study was 3 years. All 84 cows were followed during their first postpartum period, 63 during 2 and 57 during 3 consecutive postpartum periods.The resumption of ovarian function was monitored by means of a thrice weekly milk progesterone assay between calving and the first insemination.Live weight changes during the first 30 and 60 days post partum were compared between the 2 breeds and the 2 feed groups.After the second parturition, the mean live weight loss within 30 and 60 days post partum was roughly twice as high (11%) as after the first (4%) and third (6%) carvings. Breed had no significant effect on weight change. The cows in the silage group lost slightly more weight after each parturition than those in the hay-urea group. Low, but statistically significant correlations were noted between weight loss post partum and reproductive functions. The interval from calving to onset of the first visible oestrus was 6 days longer, and to pregnancy 8 days longer in cows which lost more than 10% live weight within 60 days post partum than in those which lost less than 10% (p<0.05). The fertility rate at first insemination (53.1%) was lower in cows which lost more than 10% weight than in those (74.4%) which lost less than 10% (p<0.01). Heat detection rate was not affected by weight loss.     

Effect of transport stress on physiological responses of male bovines

Forty-eight slaughter bulls were transported by road in groups of eight for approximately 30 min, 3 h and 6 h in two replicates. Animal welfare during the transport process was assessed. Loadings and unloadings were evaluated with a scoring method. Heart rates were monitored at the farm before loading and during all stages of transport. Blood samples were taken from all animals a week before transport and at sticking and analysed in terms of haematological values: hematocrit, haemoglobin, red and white blood cells (RBC and WBC), differential WBC counts and neutrophil:lymphocyte ratio. Glucose, creatine kinase, lactate and cortisol were also determined. To evaluate differences in meat quality, pH and water-holding capacity (WHC) were measured 24 h after slaughter. The loading and unloading scores were very low (low stress) but were associated with changes in heart rate, especially loading. Animals recovered their resting heart rate during the journey in medium and long transports. On the other hand, animals transported around 30 min maintained an elevated heart rate during the whole journey. All animals showed a stress response with significantly higher (p < 0.05) levels of erythrocyte series, N:L ratio, glucose and lactate. Animals transported for 3 and 6 hours had significantly (P<0.05) higher levels of cortisol than controls or 30 min transports, without differences between control and the shortest journey. Different transport times did not influence meat quality. Under good conditions, the transport had a slight effect on welfare, meat quality or physiological parameters related with stress.     

Heritabilities and genetic correlations for live weight and fibre traits in New Zealand Cashmere goats

Data were obtained at Whatawhata on the growth of goats to the yearling stage and on their cashmere production as hoggets. There were 884 animals recorded from the 1985 to 1989 birth years, comprising the progeny of 60 sires. Records from kid shearings were also obtained in the last two years. Mixed-model restricted maximum likelihood (REML) models were fitted. Heritabilities from yearling fleece records were 0.42±0.13 for fleece weight, 0.57±0.15 for yield, 0.62±0.15 for down weight, 0.35±0.12 for guard hair weight, 0.99±0.19 for down fibre diameter and 0.57±0.15 for mean down length; corresponding values from kid fleeces (23 sires only) were smaller in most cases than from yearlings, being respectively 0.14±0.06, 0.19±0.07, 0.20±0.07, 0.04±0.04, 0.19±0.07 and 0.87±0.29. The phenotypic and genotypic correlations between down weight and fibre diameter in yearlings were 0.50±0.03 and 0.81±0.08 respectively, representing an unfavourable relationship when selecting for heavier but finer down. The genetic correlations of yearling weight with down weight and down fibre diameter were slightly negative (−0.34 and −0.25), but the estimates were non-significant.     

Supplementation of cottonseed meal on feed intake, digestibility, live weight and carcass parameters of Sidama goats

The experiment was conducted at Dilla Agricultural Technical Vocational Education and Training (ATVET) College in Ethiopia using twenty-four yearling intact male Sidama goats with a mean body weight (BW) of 16.8 ± 1.14 kg (mean ± SD). The objective of the experiment was to examine the effect of different levels of cottonseed meal (CSM) supplementation on the feed intake, digestibility, BW gain, and carcass parameters of Sidama goats. The experiment consisted of 90 days of feeding trial and 10 days of digestibility trial followed by evaluation of carcass parameters at the end of the experiment. The treatments included ad libitum feeding of hay (T1, control) and daily supplementation of CSM at 200 g (T2), 300 g (T3) and 400 g (T4) per head on dry matter (DM) basis. The experimental design was a completely randomized block design. The experimental goats were blocked on initial BW and six goats were randomly assigned to each treatment. Hay DM, crude protein (CP) and neutral detergent fiber (NDF) intake were higher (P < 0.001) in the non-supplemented than in the supplemented goats, however, the contrary was true for total CP intake. Total DM intake was higher (P < 0.001) for goats supplemented with the high level of CSM than those on the control treatment. Among CSM supplemented goats, the intake of CSM DM, CP, NDF (P < 0.001) and total CP (P < 0.01) were higher in the order of T4 > T3 > T2. The high level of supplementation with CSM resulted in better (P < 0.05) apparent digestibility coefficient (DC) of DM and organic matter (OM) compared to the non-supplemented goats. The apparent DC of CP was higher (P < 0.01) for supplemented than non-supplemented goats. The non-supplemented goats had lower daily BW gain, empty BW, dressing percentage on slaughter weight base, rib-eye muscle area (P < 0.01), BW change (P < 0.001), final BW (P < 0.05) and higher feed conversion ratio (P < 0.01) than the supplemented ones. The medium level of supplementation resulted in higher daily BW gain (P < 0.01), BW change (P < 0.001), final BW (P < 0.05) and lower feed conversion ratio (P < 0.01) than the lower level of supplementation, but with no differences (P > 0.05) in these parameters with the high level of supplementation. Therefore, it is concluded that supplementation of CSM at 300 g DM per head per day resulted in better animal performance parameters in Sidama goats.     

苏打碱胁迫对多年生黑麦草的生理影响

为研究苏打碱胁迫对多年生黑麦草幼苗的生长和生理特性的影响,采用水培实验,用0.1 mol/L的Na₂CO₃ 和NaHCO₃ 溶液配置pH=8.2、pH=9.1、pH=9.9、pH=10.9四个梯度的处理液,以去离子水pH=6.5作为对照,探讨pH值对黑麦草蒸腾速率、株高、根长、含水量、叶绿素含量、丙二醛(MDA)含量以及抗氧化酶系统中超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)、过氧化物酶 (POD)活性的影响。结果表明,随着pH的升高,幼苗的株高、根长、含水量、相对蒸腾速率及叶绿素含量都显著下降,而根冠比呈先升后降的趋势。随着处理液的pH值从8.2递增至10.9,叶片中的MDA含量从对照的7.0 nmol/g FW逐步上升到30.0 nmol/g FW;而SOD活性先高后低,当pH=9.1时,最高含量为8.4 U/mg蛋白;CAT的活性则从对照的118.5 U/(min·g 蛋白)逐步递减至47.1 U/(min·g 蛋白);而POD活性呈现递增的趋势,当pH达到最高时,POD活性是对照的4倍多。     

Sex differences in stress responses to transportation in goats: Effects of gonadal hormones

The present study examined sex differences and the involvement of gonadal hormones in stress responses caused by road transportation in Shiba goats. In experiment 1, we investigated the stress responses of males and females to transportation. Plasma levels of cortisol (Cor) significantly increased during 1 h of transportation, and those in females were significantly higher than those in males. Plasma glucose (Glu) and free fatty acid (FFA) levels also increased similarly in both females and males by transportation, and there were no sex differences. Food intake following transportation decreased only in males compared with that in the basal session, in which the animals were not transported. Experiment 2 examined the involvement of gonadal hormones in stress responses to transportation using castrated males. Goats were given cholesterol (Cho), 5α‐dihydrotestosterone (DHT) or 17β‐estradiol (Es). The plasma Cor levels increased during transportation regardless of hormone treatment, and those in DHT treated goats were significantly lower than those in Cho or Es treated animals. Plasma Glu and FFA levels also increased during transportation, regardless of hormone treatment, and there were no differences between treatments. Food intake following transportation was significantly lower than that in the basal session only in goats given DHT. In conclusion, gender affects Cor secretion that is increased by transportation and the decrease of food intake following transportation in Shiba goats, and the major cause of these differences is androgen.     

The estimation of live weight based on linear traits in indigenous Tswana goats at various ages in Botswana

The objective of this study was to determine the usefulness of some linear body measurements in predicting live weight in indigenous Tswana goats at various ages. Data for this study were obtained from 2,783 goats sampled from six agricultural regions of Botswana except for Tsabong and Ghanzi districts. Fifteen farmers keeping goats were randomly selected from each district and records taken on a random sample of 4–12 animals per farm depending on the 1999 Botswana Government average district flock size. Body measurements recorded were heart girth, height at withers, body length, shoulder width, and live weight. Information on age of each animal was estimated from dentition; flock size and sex of the animal were also recorded for each farm. Regression analysis using stepwise selection method in Statistical Analysis System was used to determine prediction equations for live weight with heart girth, height at withers, body length, and shoulder width as independent variables for male and female goats of different ages. In all models, heart girth contributed most in explaining variation in body weight as shown by high partial R ² which ranged from 0.48 for female mature to 0.80 for mature male goats. Using mean square error, R ², and Mallows’ C(p), the best prediction equations were for female and male kids (R ² = 0.83 and 0.82, respectively) and mature male goats (R ² = 0.82). The poorest model was for mature female goats with R ² = 0.57. Live body weight could be estimated with accuracy from linear body measurements in Tswana goats which are unique for each sex and age. More research is required to explore using these models to develop measuring tapes for use by resource poor farmers who keep indigenous Tswana goats.