- Email: [email protected]
The effects of ventilation and showering on fattening performances and carcass traits of crossbred kids
Available online at www.sciencedirect.com
Small Ruminant Research 75 (2008) 192–198
The effects of ventilation and showering on fattening performances and carcass traits of crossbred kids N. Darcan a,∗ , S. Cankaya b b
a Department of Animal Science, Faculty of Agriculture, Cukurova University, 01330 Balcali, Adana, Turkey Department of Animal Science, Faculty of Agriculture, Ondokuz Mayis University, 55139 Kurupelit, Samsun, Turkey
Received 29 June 2007; received in revised form 20 October 2007; accepted 23 October 2007 Available online 18 December 2007
Abstract Thirty-two crossbred (75% Alpine and 25% Hair Goat) male kids (4 months old) were allocated into four experimental groups including eight kids in each. The effects of ventilation and on fattening performance and carcass quality were tested in a factorial arrangement in a completely randomized design. The results showed that total feed intake was affected by ventilation and shower and their interaction effects (P < 0.05); daily gain and final weight were affected by ventilation (P < 0.05) and ventilation × shower interaction (P < 0.01), as well. Feed intake increased with shower (58 vs. 63 kg/kid, P < 0.05) and ventilation application (58 vs. 62 kg/kid, P < 0.05), significantly. The kids which experienced cooling had higher dressing percentage, carcass weights (P < 0.01), head, feet, blood, empty gut and kidney weights, muscle growth and fat deposits than the control ones (P < 0.05). Longissimus dorsi muscles of the kids cooled by ventilation were higher than shower treatment kids’ (8.66 vs. 9.34). The muscular protein content of the individuals cooled by ventilation was higher than the other groups. Shear force values were in the range of 4.32–5.54 kg/cm2 in groups which were cooled by shower or ventilation. The taste and the tenderness of boiled and fried meat samples taken from the kids cooled with showering (4.50 vs. 5.00) were better than those of ventilation treatment groups (P < 0.05). The study shows that cooling with a ventilation provides better fattening and meat quality for kids kept under hot and humid climatic conditions and is easy to apply and more profitable. Economic analyses also supported the findings, and it was seen that an individual kept cool with ventilation increased the profit by almost 19 US dollars compared to an individual which was not kept cool. © 2007 Elsevier B.V. All rights reserved. Keywords: Goat; Fattening; Heat stress; Cooling; Carcass traits; Organoleptic traits
1. Introduction In hot climates, small ruminants try to avoid the extra heat occurring due to their metabolic activities in order to maintain their core temperature by means of some of their mechanisms. During heat stress, feed consumption decreases, while drinking increases (Silanikove, 1992).
∗ Corresponding author. Tel.: +90 322 3386813; fax: +90 322 3386576. E-mail address: [email protected] (N. Darcan).
0921-4488/$ – see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.smallrumres.2007.10.004
Weight gain is also low in parallel to feed consumption. Additionally, the animals strive hard while attempting to balance body temperature, which increases their energy need (Rout et al., 2002). Heat stress is caused by a combination of environmental factors, such as air temperature, relative humidity, solar radiation and wind speed. When exposed to hot ambient temperatures, cows will increase their respiration rate and body temperature or adjust their behavior in an attempt to maintain thermal balance (Regula et al., 2004). Lowered food consumption is a well-known effect of heat stress. The lower production is a result
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
of heat, but even more than that, it is a result of lowered food consumption. Under conditions of heat, the kids give preference to thermoregulation over other functions, such as growth or fattening performance. Lowering and preventing heat stress for increasing performances of kids in the summer requires the shielding of radiated heat and raising the loss of heat from body to environment (Rosen, 1992). In hot climates, small ruminants get rid of the extra heat occurring depending on their metabolic activities, in order to maintain their core temperature by means of some of their mechanisms. If the core temperature continues to rise despite these mechanisms, the goats experience heat stress. To prevent this, some measures which are related to improving the management, such as keeping the animals in shaded areas, ventilation, showering and making them drink cold water, have to be taken (Yousef, 1987). Beede and Collier (1986) reported that, in order to prevent heat stress, animals which are well adapted to hot climates should be chosen, better feeding conditions should be provided and barn management should be readjusted for hot climate conditions. Knizkova et al. (2002) modified microclimatic factors in the barn by opening and closing sidewall plastic curtains. They indicated that, in summertime, increased air velocity is particularly desirable because it produces a cooling effect and reduces the thermal stress. Igono et al. (1987) reported that use of spray plus ventilation is a profitable means to maximize cow comfort and lessen stress-induced decline in milk production, and economic analysis of the above-mentioned study showed a net income of 0.22 USD/(cow day) for spray plus ventilation under shade. Darcan and Guney (2002) applied showering on German Fawn × local Hair crossbred goats during the feeding season in subtropical climate conditions and accomplished $1.6 more profit per head compared to unsprayed animals. All the mentioned measures are beneficial in tropic and subtropical climates in order to improve micro-environmental conditions. However, as to humid conditions, ventilation is of great importance to dissipate the surrounding relative humidity. In practice, ventilation and showering are mostly used together, which provides cleaning of the animals as well as cooling. However, in some enterprises, only ventilation is used due to limited water sources and cost-effective measures. The aim of this study is to quantify the effects of both showering and ventilation on fattening performance and carcass quality of crossbred kids in hot and humid climates.
193
2. Materials and methods The study was carried out on crossbred goats at the Dairy Goat Research Farm, at the Faculty of Agriculture of Cukurova University. The farm is located in the east Mediterranean region of Turkey, in which subtropical weather conditions prevail with an average temperature of 35 ◦ C, 65% relative humidity and 1.1 km/h wind speed during the summer period. It is 40 m in altitude (36 59 N, 35 18 E) and annual precipitation is 450 mm. In each pen, an individual data logger had been applied. Data from thermo-hygrographs and Kinne’s (2007) formula were used to calculate the temperature-humidity index (THI). The THI value of the control, only shower, only ventilation and ventilation and shower provided pens as 90, 87, 84 and 82, respectively. The animals used in the study were composed of crossbred Alpine and Hair male kids (75% Alpine and 25% Hair Goat), which were born in the 2005 season. Thirty-two crossbred kids were allocated to four experimental groups, including eight kids each. The effects of ventilation (no ventilation, ventilation) and shower (no shower, shower) on fattening performance and carcass quality were tested in a factorial arrangement in a completely randomized design. The first group (control) was given neither shower nor ventilation, while the second one was showered from 10:00–11:00 a.m. and 14:00–15:00 p.m. every day. The third group was ventilated from 10:00–18:00. The last group took ventilation with the shower applications within the same times as the second group. For each group, the eight kids were allocated into four pens (i.e. four replications) sized 1.80 m × 2.10 m. The Kentucky system was performed for cooling the goats. Parallel sprinkler pipelines were mounted 2 m above the ground. In total, 24 sprinklers supplied 2.5 l water/min. Two axial ventilations (air movement 1.5 m/h) were mounted (45 cm diameter) in the middle of the paddocks of experimental kids (Bucklin et al., 1991). Kids were weaned at 3 months old. Before weaning, they had free access to kid grower concentrates and medium quality alfalfa hay from 2 weeks old during the pre-weaning period. After weaning, a 1-month transition period was applied for adaptation to pens and fattening diets. The fattening experiment was launched on 1 July 2005 and finished on 27 August 2005 (duration of 58 days, until slaughtering time). Kids were fed ad libitum with total mixed rations containing 90% concentrate (2550 kcal ME/kg, 18% CP) and 10% alfalfa hay chopped to 1.5–2 cm lengths. All kids received water freely. The feed intake was recorded daily and the weight gain was determined weekly. Following the fattening period, all kids were slaughtered. Their carcass analysis was carried out according to standard Mediterranean carcass cutting methods (as described by Colomer-Rocher et al., 1987). Weight, blood amount, head, feet, skin and visceral organs’ sizes were measured during and just after slaughtering, when the carcass was still hot. After 24 h storage at +4 ◦ C, the fat depth, thickness and broadness over the longissimus dorsi muscle were measured. Dressing percentage was measured on the cold carcass. The carcass was then divided into two parts, and the left side
194
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
SVij is the effect of interaction between shower and ventilation; eij = residual error. DUNCAN Multiple Range Test was then utilized to separate these differences (SPSS 10.0 V., 1999). Also, Kruskal–Wallis test, a nonparametric test, was performed to test whether there were any differences among the four traits (1 = control or no treatments, 2 = shower, 3 = ventilation, 4 = shower and ventilation) regarding the sensory evaluation. Then, Dunn’s multiple comparison tests were applied to determine any further differences among the groups.
was dissected as neck, front leg, thigh, rump and hip. These parts were dissected to bone, fat, muscle and others (waste etc.). During carcass study, some samples were taken from the longissimus dorsi muscle and moisture, pH, protein, ash and fat levels were determined. Muscle pH was determined using a WTW pH 240i pocket pH-meter with a combined electrode, by insertion into the longissimus dorsi muscle on the chilled carcass. Moisture was determined in muscles using official methods (AOAC, 2000). The sixth sirloin steak was used for the intramuscular fat determinations (IMFat) (Official Methods of Analysis (BOE 29/8/1979) and International Norms ISO R-1443), proteins (Official Methods of Analysis (BOE 29/8/1979) and International Norms ISO R-937) and ash (Official Methods of Analysis (BOE 29/8/1979) and International Norms ISO R-936) (Sarri´es and Beriain, 2005). The vastus group of muscles was used for determining shear force values. The muscles were weighed and then cooked in a plastic bag in a water bath at 85 ◦ C for 45 min, until an internal temperature of 70 ◦ C was achieved. Muscle cores with cross sections of 1 cm × 1 cm and at least 3 cm long were cut parallel to the muscle fibers and shear force values determined by Warner–Bratzler shear force apparatus (Dhanda et al., 1999). Organoleptic evaluation was carried out on supraspinatus and triceps branchii muscle samples. The muscle samples were evaluated before cooking (raw), boiled (20 min in a boiling water bath with 0.5% salt) and fried (20 min fried). The sensory evaluation of cooked meat for colour, odour, juiciness, tenderness and overall palatability were performed using a five-point hedonic scale (5 = excellent, 1 = very poor) by a taste panel. Ten trained panelists were used for the taste panel. The data were recorded based on their preference for the samples (Sen et al., 2004).
3. Results and discussion The results (Table 1) show that total feed intake was affected by ventilation and shower and their interaction effects (P < 0.05); daily gain and final weight were affected by ventilation (P < 0.05) and, ventilation × shower interaction (P < 0.01), as well. Feed intake increased significantly with shower (+5 kg/kid, P < 0.05) and ventilation application (+4 kg/kid, P < 0.05), significantly. While the ventilated kids did not change their feed intake by shower, the non-ventilated kids did increase their feed intake (+8.5 kg/kid) by shower. Direct wetting (evaporative cooling) or supplying air velocity around livestock in the hot season is the most effective ways to alleviate heat stress. These applications are associated with physiological responses of the animals, such as decreasing body core temperature, heart rate, respiration rate etc. Kids cooled with direct wetting with shower or ventilation had lower rectal temperature (−0.9 ◦ C and −1.0 ◦ C, respectively) than the concomitant counterparts. Depending on the decrease in rectal temperature, the kids may decrease maintenance cost (Huber et al., 1994) and they could improve feed intake (+8 kg) and daily gain (+25 g/d). The results obtained in the present study supported that daily gain and final body weight increased with the air velocity supplied by ventilation and by wetting in non-ventilated kids. Increasing air velocity around the animal may help dissemination of
2.1. Statistical analysis An analysis of variance was performed in a completely randomized design with a 2 × 2 factorial arrangement of treatments (shower and ventilation levels): Yˆ i = μ + Si + Vj + SVij + eij where Yˆ i is observation value; μ is the overall mean; Si is the effect of the ith shower treatment (1 = without shower, 2 = with shower); Vj is the effect of the jth ventilation treatment (1 = without ventilation, 2 = with ventilation);
Table 1 Fattening performances of kids subjected to shower (S) and/or ventilation (V) treatments Ventilation
No
Shower
Noa
Yes
S.E.M.
Yes
No
Yes
Initial weight (kg/kid) Final weight (kg/kid) Total weight gain (kg/kid) Total food consumed (kg/kid) Average daily weight gain (g/day) FCR (kg feed/kg gain)
20.20 25.13 b 4.93 54.13 b 0.09 b 10.9
20.45 28.10 a 7.65 62.68 a 0.13 ab 8.1
20.32 30.45 a 10.09 61.62 a 0.17 a 6.1
20.36 28.55 a 8.23 64.05 a 0.14 ab 7.7
Effects S
V
S×V
0.087 0.813
NS NS
NS *
NS **
2.879 0.026
* NS
* *
* **
Different letters (a, b) within row differ significantly (*P < 0.05; **P < 0.01; NS: not significant, P > 0.05). S.E.M.: standard errors of the means. a Control group.
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
195
age, carcass (P < 0.01), head, feet, blood, empty gut and kidney weights, additionally, muscle growth and fat deposits more than the control ones (P < 0.05). Higher dressing yield and organs can be related to the higher pre-slaughter weight or relative fatness of these carcasses, as indicated by Sen et al. (2004). The weights of organs matched the other researchers’ findings (Darcan and Guney, 2002; Dhanda et al., 1999; Kocak, 1995; Nitter, 1975), so they are in the normal range. Also, these parts did not have economic importance: they are only used for evaluation of the carcass yield. However, the longissimus dorsi (loin eye muscle) area is one of the main indicators of carcass performance in fattening studies (Colomer-Rocher et al., 1987; Nitter, 1975). In this study, longissimus dorsi muscles of the kids cooled by ventilation were higher than those of shower treatment kids (8.66 vs. 9.34 cm2 ). Thus, it can be said that the amount of carcass tissue which has economic importance, such as loin eye muscle, were positively affected, especially by cooling by ventilation. This is similar for fat contents of the carcasses; kids not experiencing heat stress consumed more food, and since they do not need so much of this energy to deal with heat stress, they store the
the heat load under heat stress conditions by taking away heated air from around the animal and/or inside of the barn. Positive effects of evaporative cooling (wetting) on performance in lactating animals (Darcan et al., in press; Serbester et al., 2004) and growing animals (Darcan and Guney, 2002) were shown in the previous studies; however, some studies (Goncu and Ozkutuk, 2003) argued that wetting the animal may increase relative humidity around the animal and/or barn and heat loss from the animal’s body may be decreased due to difficulties in water evaporation in wetted animal skin under such conditions. The results in the present study revealed that wetting only is sufficient for good performance of kids under heat stress conditions as the kids receiving cooling (except the control group with no ventilation and no shower) are similar in respect to feed intake, daily gain and final body weight. The data related to the kid carcasses were briefly given in Table 2. Dressing percentage and carcass characteristics were affected by ventilation and shower and their interaction effects (P < 0.05), as well; the kids which experienced cooling had higher dressing percent-
Table 2 Carcass traits of experimental kids subjected to shower (S) and/or ventilation (V) treatments Ventilation
No
Shower
Noa
Yes
S.E.M.
Yes
No
Yes
Slaughter weight (kg) Hot carcass weight (kg) Cold carcass weight (kg) Shrinkage (g) Dressing (%) Head (kg) Feet (kg) Blood (kg) Liver (kg) Heart (kg) Kidney (kg) Rumen (empty, kg) Intestines (empty, kg) Digestive content (kg) L. dorsi muscle area (cm2 ) Back fat thickness (mm) Kidney and pelvis fat (kg) Mesenteric and omental fat (kg)
25.13 b 12.68 b 11.60 b 1.08 46 1.92 b 0.75 ab 1.18 b 1.13 0.39 0.12 b 1.03 0.58 b 3.39 b 7.39 b 0.20 b 0.42 b 1.10 b
28.10 a 14.63 a 13.58 ab 1.05 48 2.08 ab 0.80 ab 1.28 a 1.25 0.41 0.17 b 1.13 0.80 a 4.33 a 7.42 b 0.33 b 0.59 a 1.38 ab
30.45 a 16.83 a 15.75 a 1.08 51 2.20 a 0.85 a 1.30 a 1.28 0.43 0.30 a 1.20 0.70 a 4.81 a 9.91 a 0.62 a 0.40 b 1.48 a
28.55 a 14.25 ab 13.83 ab 1.42 48 2.03 b 0.70 b 1.17 b 1.33 0.39 0.20 ab 1.10 0.80 a 4.68 a 8.78 a 0.58 a 0.62 a 1.41 a
Carcass dissection Intramuscular fat (%) Subcutaneous fat (%) Muscle (%) Bone (%) Others (%)
2b 8b 68 b 18 a 2
4a 10 a 70 a 16 b 2
5a 9a 71 a 15 b 2
5a 10 a 72 a 14 b 1
Effects S
V
S×V
0.893 0.513 0.681
NS NS NS
* * **
** ** **
0.043 0.031 0.013 0.086 0.026 0.038 0.063 0.034 0.241 0.453 0.047 0.039 0.092
NS NS NS NS NS NS NS * NS NS NS * NS
NS NS NS NS NS * NS NS * * * NS NS
* * * NS NS * NS * * * ** ** *
0.036 0.042 0.041 0.045 0.311
* * NS * NS
* * * NS NS
* * * * NS
Different letters (a, b) within row differ significantly (*P < 0.05; **P < 0.01; NS: not significant, P > 0.05). S.E.M.: standard errors of the means. a Control group.
196
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
Table 3 Chemical and physical analyses of meats subjected to shower (S) and/or ventilation (V) treatments Ventilation
No
Yes
S.E.M.
Shower
Noa
Yes
No
Yes
Moisture (%) Protein (%) Ash (%) Fat (%) Collagen (%) pH WB shear force (kg)
69.55 15.35 0.68 12.42 a 0.64 5.94 11.26 a
70.33 15.50 0.69 12.25 a 0.67 5.75 10.54 a
70.33 15.55 0.70 12.23 a 0.65 5.73 9.32 b
71.14 15.41 0.71 11.53 b 0.62 5.77 9.67 b
0.414 0.087 0.341 0.216 0.023 0.092 0.024
Effects S
V
S×V
NS NS NS NS NS NS *
NS NS NS NS NS NS *
NS NS NS * NS NS *
Different letters (a, b) within row differ significantly (*P < 0.05; **P < 0.01; NS: not significant, P > 0.05). S.E.M.: standard errors of the means. a Control group.
surplus in their body as fat deposits, as reported by Sen et al. (2004) and Mader (2007). In carcass evaluation, the fat deposits were stored preferably as intramuscular fat (Nitter, 1975; Colomer-Rocher et al., 1987). The distribution of fat into the muscles of cooled kids was better when compared to the non-cooled (control) kids’ carcasses, so cooling has positive effects on the carcass quality in goats, as well (Table 2). The mean values belonging to the chemical analyses of the tissues taken from the carcasses are given in Table 3. There were not significant differences between the groups in terms of moisture, protein, collagen and pH (P > 0.05), while the fat contents were significantly different (P < 0.05). These findings matched with the data that were obtained during the carcass study. The fat contents of kids were cooled by both shower and ventilation lower than that of the other groups. Physical/chemical attributes of meats are given in Table 3, as well. There were significant differences in shear force (P < 0.05) of meats of different groups. When kids were
cooled by ventilation, their meat was tenderer than the other kids’ meat. Shear force values were in the range of 4.32–5.54 kg/cm2 in groups which were cooled by shower or ventilation. These values were low compared to 6.0 kg/cm2 observed by Johnson et al. (1995), who were cited by Dhanda et al. (1999), while being quite a lot higher than those of the findings of Dhanda et al. (1999). However, the muscles of control kids were higher than the other treatment groups and also than the findings of Dhanda et al. (1999). Reason of this variation is intramuscular fat contents of the muscles (Colomer-Rocher et al., 1987). The organoleptic panel results of the meat samples taken from kid carcasses are given in Table 4. It was observed that the raw meat samples were similar in terms of colour and odour in all groups, but the marbling rates of the kids somewhat cooled, especially of the kids cooled with a ventilation, were higher than the control ones. The marbling of control kids were worst than the cooled kids (P < 0.05) which means that intramus-
Table 4 Organoleptic panel results Traits
Control
Shower
Ventilation
Shower and ventilation
S.E.M.
Significance
Raw Colour Odour Marbling
4.25 5.00 3.75 b
4.25 5.00 4.00 a
4.00 5.00 4.75 a
4.75 4.75 5.00 a
0.125 0.250 0.085
NS NS *
Fried Odour Flavour Chewiness
5.00 3.25b 3.00b
5.00 4.75 a 4.50 a
5.00 5.00 a 4.00 a
5.00 5.00 a 4.75 a
0.000 0.085 0.269
NS * *
Boiled Odour Flavour Chewiness
5.00 3.75b 3.00b
5.00 4.50 a 4.50 a
4.75 4.75 a 5.00 a
5.00 4.75 a 5.00 a
0.101 0.129 0.232
NS * *
S.E.M.: standard errors of the means; Different letters (a, b) within row differ significantly (*P < 0.05; NS: not significant, P > 0.05).
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
197
Table 5 Economic analyses of shower and ventilation application on male kids under heat stress Ventilation
No
Shower
No
Weight gain (USD/(kid trial))a Feed consumption (USD/(day kid))b Water (USD/(m3 day 8 kids))c Electricity (USD/(kwh day kid))d
0 0 0 0
Total
0
a b c d
Yes Yes
No
Yes
+11.15 −1.99 −0.1 0
+21.15 −1.75 0 −0.5
+13.53 −2.31 −0.1 −0.5
+9.06
+18.90
+10.62
1 kg live weight 4.1 USD. 1 kg concentrate 0.23 USD. 1 m3 drinking water 0.2 USD (4 m3 days for 8 kids). 1 kw/h electricity 0.5 USD (total 8 kwh/(day/8 kids)).
cular fat distribution is also worst than cooled kids. The taste and the tenderness of boiled and fried meat samples taken from the kids cooled with a shower (4.50 vs. 5.00) were better than ventilation treatment groups (P < 0.05). Thus the meat flavour of the kids which were cooled either by ventilation or by shower was better than the control ones. There was no research that could available to discuss these findings. Results of the economic analyses of this experiment are summarized in Table 5. When the value given in the control group was zero, all of the cooled individuals were more profitable than the control kids. The numbers given in Table 5 just represent one kid; therefore, when it is estimated for eight individuals, this will mean 152.2 USD higher profits, which cannot be overlooked considering profitability. 4. Conclusion The results obtained in the present study indicate that different cooling methods, including shower and ventilation, lead to different fattening scores and different carcass qualities. Additionally, supplying a shower and ventilation improved weight gain by +2.72–3.16 kg and feed consumption by −2.8 to 4.8 kg. Also, the carcass quality and total muscle and fat distribution of the carcasses improved. The results have provided some important clues and indicators on how to promote fattening performance and the carcass quality of the kids in the Mediterranean region, where hot and humid weather prevails. This was quite clear especially in cooling only by ventilation and shower, which resulted in the best performances of all the groups. Although showering was profitable, the results were much better when ventilation was also applied. Economic analyses also supported the findings, and it was seen that an individual kept cool with ventilation increased the profit by 19 USD, compared to
an individual which was not kept cool. This number is quite important considering profitability. Acknowledgements This study was supported by VHAG-2083 Project of TUBITAK. Authors’ thank Ahmet Koluman, Murat Gorgulu, Mehmet Mamger and Mary Lynn Varner for their valuable help. References AOAC, 2000. Moisture content. 950.46. In: Official Methods of Analysis, 17th ed. Association of Official Analytical Chemists, Gaithersburgh, MD. Beede, D.K., Collier, J., 1986. Potential nutritional strategies for intensively managed cattle during thermal stress. J. Anim. Sci. 62, 543–548. Bucklin, R.A., Turner, L.W., Beede, D.K., Bray, D.R., Hemken, R.W., 1991. Methods to relieve heat stress for dairy cows in hot, humid climates. Appl. Eng. Agric. 7 (2), 241–246. Colomer-Rocher, F., Morand-Fehr, P., Kirton, A.H., 1987. Standard methods and procedures for goat carcass evaluation, jointing and tissue separation. Livest. Prod. Sci. 17, 149–159. Darcan, N., Guney, O., 2002. Effect of spraying on growth and feed efficiency of kids under subtropical climate. Small Rumin. Res. 43, 189–190. Darcan, N., Cedden, F., Cankaya, S., in press. Spraying effects on goat welfare in hot and humid climate. Ital. J. Anim. Sci. Dhanda, J.S., Taylor, D.G., Murray, P.J., McCosher, J.E., 1999. The influence of goat genotype on the production of capretto and chevon carcasses. 2. Meat quality. Meat Sci. 52, 363–367. Goncu, S., Ozkutuk, K., 2003. Shower effect at summer time on fattening performances of black and white bullocks. J. Appl. Anim. Res. 23 (1), 123–127. Huber, J.T., Higginbotham, G., Gomez-Alarcon, R.A., Taylor, R.B., Chen, K.H., Wu, Z., 1994. Heat stress interaction with protein, supplemental fat and fungal cultures. J. Dairy Sci. 77, 2080–2090. Igono, M.O., Johnson, H.D., Steevens, B.J., Krause, G.F., Shanklin, M.D., 1987. Physiological, productive and economic benefits of shade spray and ventilation system versus shade for Holstein cows during summer heat. J. Dairy Sci. 70, 1069–1079.
198
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
Kinne, M., 2007. Breaching heat stress comfort zones. http:// kinne.net/heatstrs.htm, last access date: October 15, 2007. Knizkova, I., Kunc, P., Koubkova, M., Flusser, J., Dolezal, O., 2002. Evaluation of naturally ventilated barn management by thermographic method. Livest. Prod. Sci. 77, 349–353. Kocak, H., 1995. Effects of castration on fattening performances of German fawn × hair crossbred kids. Master Thesis. No.: 949. Institute of Basic and Applied Sciences, Cukurova Univ., Adana, Turkey. p. 48. Mader, T.L., 2007. Heat stress effects on feedlot cattle and mitigation strategies. In: 22nd Annual Southwest Nutrition & Management Conference, Tempe, AZ, Feb 22–23 2007. Nitter, G., 1975. Preliminary results with intensive fattening of young goats. Kleinviehzuehter 23, 316–320. Regula, G., Danuser, J., Spycher, B., Wechsler, B., 2004. Health and welfare of dairy cows in different husbandry systems in Switzerland. Prev. Vet. Med. 66, 247–264. Rosen, S., 1992. Heat stress management in Israel. Extension Service, Ministry of Agriculture, Extensions, Beit Shean, Israel, pp. 83–90.
Rout, P.K., Mandal, A., Singh, L.B., Roy, R., 2002. Studies on behavioral patterns in Jamnapari goats. Small Rumin. Res. 43, 185–188. Sarri´es, M.V., Beriain, M.J., 2005. Carcass characteristics and meat quality of male and female foals. Meat Sci. 70 (1), 141–152. Sen, A.R., Santra, A., Karim, S.A., 2004. Carcass yield, composition and meat quality attributes of sheep and goat under semi-arid conditions. Meat Sci. 66, 757–763. Serbester, U., Gorgulu, M., Kutlu, H.R., Yurtseven, S., Arieli, A., Kowalski, Z.M., 2004. The effects of sprinkler + ventilation, fish meal or dietary fat on milk yield and milk composition of dairy cows in mid lactation during summer. J. Anim. Feed Sci. 14, 639–653. Silanikove, N., 1992. Effects of water scarcity and hot environment on appetite and digestion in ruminants: a review. Livest. Prod. Sci. 30, 175–194. SPSS Inc., 1999. SPSS for Windows. Release, 10.0. Copyright SPSS Inc., Chicago, USA. Yousef, M.K., 1987. Principles of bioclimatology and adaptation of livestock. Elsevier Publ., Holland, WAS, B5, 17–31.
Small Ruminant Research 75 (2008) 192–198
The effects of ventilation and showering on fattening performances and carcass traits of crossbred kids N. Darcan a,∗ , S. Cankaya b b
a Department of Animal Science, Faculty of Agriculture, Cukurova University, 01330 Balcali, Adana, Turkey Department of Animal Science, Faculty of Agriculture, Ondokuz Mayis University, 55139 Kurupelit, Samsun, Turkey
Received 29 June 2007; received in revised form 20 October 2007; accepted 23 October 2007 Available online 18 December 2007
Abstract Thirty-two crossbred (75% Alpine and 25% Hair Goat) male kids (4 months old) were allocated into four experimental groups including eight kids in each. The effects of ventilation and on fattening performance and carcass quality were tested in a factorial arrangement in a completely randomized design. The results showed that total feed intake was affected by ventilation and shower and their interaction effects (P < 0.05); daily gain and final weight were affected by ventilation (P < 0.05) and ventilation × shower interaction (P < 0.01), as well. Feed intake increased with shower (58 vs. 63 kg/kid, P < 0.05) and ventilation application (58 vs. 62 kg/kid, P < 0.05), significantly. The kids which experienced cooling had higher dressing percentage, carcass weights (P < 0.01), head, feet, blood, empty gut and kidney weights, muscle growth and fat deposits than the control ones (P < 0.05). Longissimus dorsi muscles of the kids cooled by ventilation were higher than shower treatment kids’ (8.66 vs. 9.34). The muscular protein content of the individuals cooled by ventilation was higher than the other groups. Shear force values were in the range of 4.32–5.54 kg/cm2 in groups which were cooled by shower or ventilation. The taste and the tenderness of boiled and fried meat samples taken from the kids cooled with showering (4.50 vs. 5.00) were better than those of ventilation treatment groups (P < 0.05). The study shows that cooling with a ventilation provides better fattening and meat quality for kids kept under hot and humid climatic conditions and is easy to apply and more profitable. Economic analyses also supported the findings, and it was seen that an individual kept cool with ventilation increased the profit by almost 19 US dollars compared to an individual which was not kept cool. © 2007 Elsevier B.V. All rights reserved. Keywords: Goat; Fattening; Heat stress; Cooling; Carcass traits; Organoleptic traits
1. Introduction In hot climates, small ruminants try to avoid the extra heat occurring due to their metabolic activities in order to maintain their core temperature by means of some of their mechanisms. During heat stress, feed consumption decreases, while drinking increases (Silanikove, 1992).
∗ Corresponding author. Tel.: +90 322 3386813; fax: +90 322 3386576. E-mail address: [email protected] (N. Darcan).
0921-4488/$ – see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.smallrumres.2007.10.004
Weight gain is also low in parallel to feed consumption. Additionally, the animals strive hard while attempting to balance body temperature, which increases their energy need (Rout et al., 2002). Heat stress is caused by a combination of environmental factors, such as air temperature, relative humidity, solar radiation and wind speed. When exposed to hot ambient temperatures, cows will increase their respiration rate and body temperature or adjust their behavior in an attempt to maintain thermal balance (Regula et al., 2004). Lowered food consumption is a well-known effect of heat stress. The lower production is a result
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
of heat, but even more than that, it is a result of lowered food consumption. Under conditions of heat, the kids give preference to thermoregulation over other functions, such as growth or fattening performance. Lowering and preventing heat stress for increasing performances of kids in the summer requires the shielding of radiated heat and raising the loss of heat from body to environment (Rosen, 1992). In hot climates, small ruminants get rid of the extra heat occurring depending on their metabolic activities, in order to maintain their core temperature by means of some of their mechanisms. If the core temperature continues to rise despite these mechanisms, the goats experience heat stress. To prevent this, some measures which are related to improving the management, such as keeping the animals in shaded areas, ventilation, showering and making them drink cold water, have to be taken (Yousef, 1987). Beede and Collier (1986) reported that, in order to prevent heat stress, animals which are well adapted to hot climates should be chosen, better feeding conditions should be provided and barn management should be readjusted for hot climate conditions. Knizkova et al. (2002) modified microclimatic factors in the barn by opening and closing sidewall plastic curtains. They indicated that, in summertime, increased air velocity is particularly desirable because it produces a cooling effect and reduces the thermal stress. Igono et al. (1987) reported that use of spray plus ventilation is a profitable means to maximize cow comfort and lessen stress-induced decline in milk production, and economic analysis of the above-mentioned study showed a net income of 0.22 USD/(cow day) for spray plus ventilation under shade. Darcan and Guney (2002) applied showering on German Fawn × local Hair crossbred goats during the feeding season in subtropical climate conditions and accomplished $1.6 more profit per head compared to unsprayed animals. All the mentioned measures are beneficial in tropic and subtropical climates in order to improve micro-environmental conditions. However, as to humid conditions, ventilation is of great importance to dissipate the surrounding relative humidity. In practice, ventilation and showering are mostly used together, which provides cleaning of the animals as well as cooling. However, in some enterprises, only ventilation is used due to limited water sources and cost-effective measures. The aim of this study is to quantify the effects of both showering and ventilation on fattening performance and carcass quality of crossbred kids in hot and humid climates.
193
2. Materials and methods The study was carried out on crossbred goats at the Dairy Goat Research Farm, at the Faculty of Agriculture of Cukurova University. The farm is located in the east Mediterranean region of Turkey, in which subtropical weather conditions prevail with an average temperature of 35 ◦ C, 65% relative humidity and 1.1 km/h wind speed during the summer period. It is 40 m in altitude (36 59 N, 35 18 E) and annual precipitation is 450 mm. In each pen, an individual data logger had been applied. Data from thermo-hygrographs and Kinne’s (2007) formula were used to calculate the temperature-humidity index (THI). The THI value of the control, only shower, only ventilation and ventilation and shower provided pens as 90, 87, 84 and 82, respectively. The animals used in the study were composed of crossbred Alpine and Hair male kids (75% Alpine and 25% Hair Goat), which were born in the 2005 season. Thirty-two crossbred kids were allocated to four experimental groups, including eight kids each. The effects of ventilation (no ventilation, ventilation) and shower (no shower, shower) on fattening performance and carcass quality were tested in a factorial arrangement in a completely randomized design. The first group (control) was given neither shower nor ventilation, while the second one was showered from 10:00–11:00 a.m. and 14:00–15:00 p.m. every day. The third group was ventilated from 10:00–18:00. The last group took ventilation with the shower applications within the same times as the second group. For each group, the eight kids were allocated into four pens (i.e. four replications) sized 1.80 m × 2.10 m. The Kentucky system was performed for cooling the goats. Parallel sprinkler pipelines were mounted 2 m above the ground. In total, 24 sprinklers supplied 2.5 l water/min. Two axial ventilations (air movement 1.5 m/h) were mounted (45 cm diameter) in the middle of the paddocks of experimental kids (Bucklin et al., 1991). Kids were weaned at 3 months old. Before weaning, they had free access to kid grower concentrates and medium quality alfalfa hay from 2 weeks old during the pre-weaning period. After weaning, a 1-month transition period was applied for adaptation to pens and fattening diets. The fattening experiment was launched on 1 July 2005 and finished on 27 August 2005 (duration of 58 days, until slaughtering time). Kids were fed ad libitum with total mixed rations containing 90% concentrate (2550 kcal ME/kg, 18% CP) and 10% alfalfa hay chopped to 1.5–2 cm lengths. All kids received water freely. The feed intake was recorded daily and the weight gain was determined weekly. Following the fattening period, all kids were slaughtered. Their carcass analysis was carried out according to standard Mediterranean carcass cutting methods (as described by Colomer-Rocher et al., 1987). Weight, blood amount, head, feet, skin and visceral organs’ sizes were measured during and just after slaughtering, when the carcass was still hot. After 24 h storage at +4 ◦ C, the fat depth, thickness and broadness over the longissimus dorsi muscle were measured. Dressing percentage was measured on the cold carcass. The carcass was then divided into two parts, and the left side
194
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
SVij is the effect of interaction between shower and ventilation; eij = residual error. DUNCAN Multiple Range Test was then utilized to separate these differences (SPSS 10.0 V., 1999). Also, Kruskal–Wallis test, a nonparametric test, was performed to test whether there were any differences among the four traits (1 = control or no treatments, 2 = shower, 3 = ventilation, 4 = shower and ventilation) regarding the sensory evaluation. Then, Dunn’s multiple comparison tests were applied to determine any further differences among the groups.
was dissected as neck, front leg, thigh, rump and hip. These parts were dissected to bone, fat, muscle and others (waste etc.). During carcass study, some samples were taken from the longissimus dorsi muscle and moisture, pH, protein, ash and fat levels were determined. Muscle pH was determined using a WTW pH 240i pocket pH-meter with a combined electrode, by insertion into the longissimus dorsi muscle on the chilled carcass. Moisture was determined in muscles using official methods (AOAC, 2000). The sixth sirloin steak was used for the intramuscular fat determinations (IMFat) (Official Methods of Analysis (BOE 29/8/1979) and International Norms ISO R-1443), proteins (Official Methods of Analysis (BOE 29/8/1979) and International Norms ISO R-937) and ash (Official Methods of Analysis (BOE 29/8/1979) and International Norms ISO R-936) (Sarri´es and Beriain, 2005). The vastus group of muscles was used for determining shear force values. The muscles were weighed and then cooked in a plastic bag in a water bath at 85 ◦ C for 45 min, until an internal temperature of 70 ◦ C was achieved. Muscle cores with cross sections of 1 cm × 1 cm and at least 3 cm long were cut parallel to the muscle fibers and shear force values determined by Warner–Bratzler shear force apparatus (Dhanda et al., 1999). Organoleptic evaluation was carried out on supraspinatus and triceps branchii muscle samples. The muscle samples were evaluated before cooking (raw), boiled (20 min in a boiling water bath with 0.5% salt) and fried (20 min fried). The sensory evaluation of cooked meat for colour, odour, juiciness, tenderness and overall palatability were performed using a five-point hedonic scale (5 = excellent, 1 = very poor) by a taste panel. Ten trained panelists were used for the taste panel. The data were recorded based on their preference for the samples (Sen et al., 2004).
3. Results and discussion The results (Table 1) show that total feed intake was affected by ventilation and shower and their interaction effects (P < 0.05); daily gain and final weight were affected by ventilation (P < 0.05) and, ventilation × shower interaction (P < 0.01), as well. Feed intake increased significantly with shower (+5 kg/kid, P < 0.05) and ventilation application (+4 kg/kid, P < 0.05), significantly. While the ventilated kids did not change their feed intake by shower, the non-ventilated kids did increase their feed intake (+8.5 kg/kid) by shower. Direct wetting (evaporative cooling) or supplying air velocity around livestock in the hot season is the most effective ways to alleviate heat stress. These applications are associated with physiological responses of the animals, such as decreasing body core temperature, heart rate, respiration rate etc. Kids cooled with direct wetting with shower or ventilation had lower rectal temperature (−0.9 ◦ C and −1.0 ◦ C, respectively) than the concomitant counterparts. Depending on the decrease in rectal temperature, the kids may decrease maintenance cost (Huber et al., 1994) and they could improve feed intake (+8 kg) and daily gain (+25 g/d). The results obtained in the present study supported that daily gain and final body weight increased with the air velocity supplied by ventilation and by wetting in non-ventilated kids. Increasing air velocity around the animal may help dissemination of
2.1. Statistical analysis An analysis of variance was performed in a completely randomized design with a 2 × 2 factorial arrangement of treatments (shower and ventilation levels): Yˆ i = μ + Si + Vj + SVij + eij where Yˆ i is observation value; μ is the overall mean; Si is the effect of the ith shower treatment (1 = without shower, 2 = with shower); Vj is the effect of the jth ventilation treatment (1 = without ventilation, 2 = with ventilation);
Table 1 Fattening performances of kids subjected to shower (S) and/or ventilation (V) treatments Ventilation
No
Shower
Noa
Yes
S.E.M.
Yes
No
Yes
Initial weight (kg/kid) Final weight (kg/kid) Total weight gain (kg/kid) Total food consumed (kg/kid) Average daily weight gain (g/day) FCR (kg feed/kg gain)
20.20 25.13 b 4.93 54.13 b 0.09 b 10.9
20.45 28.10 a 7.65 62.68 a 0.13 ab 8.1
20.32 30.45 a 10.09 61.62 a 0.17 a 6.1
20.36 28.55 a 8.23 64.05 a 0.14 ab 7.7
Effects S
V
S×V
0.087 0.813
NS NS
NS *
NS **
2.879 0.026
* NS
* *
* **
Different letters (a, b) within row differ significantly (*P < 0.05; **P < 0.01; NS: not significant, P > 0.05). S.E.M.: standard errors of the means. a Control group.
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
195
age, carcass (P < 0.01), head, feet, blood, empty gut and kidney weights, additionally, muscle growth and fat deposits more than the control ones (P < 0.05). Higher dressing yield and organs can be related to the higher pre-slaughter weight or relative fatness of these carcasses, as indicated by Sen et al. (2004). The weights of organs matched the other researchers’ findings (Darcan and Guney, 2002; Dhanda et al., 1999; Kocak, 1995; Nitter, 1975), so they are in the normal range. Also, these parts did not have economic importance: they are only used for evaluation of the carcass yield. However, the longissimus dorsi (loin eye muscle) area is one of the main indicators of carcass performance in fattening studies (Colomer-Rocher et al., 1987; Nitter, 1975). In this study, longissimus dorsi muscles of the kids cooled by ventilation were higher than those of shower treatment kids (8.66 vs. 9.34 cm2 ). Thus, it can be said that the amount of carcass tissue which has economic importance, such as loin eye muscle, were positively affected, especially by cooling by ventilation. This is similar for fat contents of the carcasses; kids not experiencing heat stress consumed more food, and since they do not need so much of this energy to deal with heat stress, they store the
the heat load under heat stress conditions by taking away heated air from around the animal and/or inside of the barn. Positive effects of evaporative cooling (wetting) on performance in lactating animals (Darcan et al., in press; Serbester et al., 2004) and growing animals (Darcan and Guney, 2002) were shown in the previous studies; however, some studies (Goncu and Ozkutuk, 2003) argued that wetting the animal may increase relative humidity around the animal and/or barn and heat loss from the animal’s body may be decreased due to difficulties in water evaporation in wetted animal skin under such conditions. The results in the present study revealed that wetting only is sufficient for good performance of kids under heat stress conditions as the kids receiving cooling (except the control group with no ventilation and no shower) are similar in respect to feed intake, daily gain and final body weight. The data related to the kid carcasses were briefly given in Table 2. Dressing percentage and carcass characteristics were affected by ventilation and shower and their interaction effects (P < 0.05), as well; the kids which experienced cooling had higher dressing percent-
Table 2 Carcass traits of experimental kids subjected to shower (S) and/or ventilation (V) treatments Ventilation
No
Shower
Noa
Yes
S.E.M.
Yes
No
Yes
Slaughter weight (kg) Hot carcass weight (kg) Cold carcass weight (kg) Shrinkage (g) Dressing (%) Head (kg) Feet (kg) Blood (kg) Liver (kg) Heart (kg) Kidney (kg) Rumen (empty, kg) Intestines (empty, kg) Digestive content (kg) L. dorsi muscle area (cm2 ) Back fat thickness (mm) Kidney and pelvis fat (kg) Mesenteric and omental fat (kg)
25.13 b 12.68 b 11.60 b 1.08 46 1.92 b 0.75 ab 1.18 b 1.13 0.39 0.12 b 1.03 0.58 b 3.39 b 7.39 b 0.20 b 0.42 b 1.10 b
28.10 a 14.63 a 13.58 ab 1.05 48 2.08 ab 0.80 ab 1.28 a 1.25 0.41 0.17 b 1.13 0.80 a 4.33 a 7.42 b 0.33 b 0.59 a 1.38 ab
30.45 a 16.83 a 15.75 a 1.08 51 2.20 a 0.85 a 1.30 a 1.28 0.43 0.30 a 1.20 0.70 a 4.81 a 9.91 a 0.62 a 0.40 b 1.48 a
28.55 a 14.25 ab 13.83 ab 1.42 48 2.03 b 0.70 b 1.17 b 1.33 0.39 0.20 ab 1.10 0.80 a 4.68 a 8.78 a 0.58 a 0.62 a 1.41 a
Carcass dissection Intramuscular fat (%) Subcutaneous fat (%) Muscle (%) Bone (%) Others (%)
2b 8b 68 b 18 a 2
4a 10 a 70 a 16 b 2
5a 9a 71 a 15 b 2
5a 10 a 72 a 14 b 1
Effects S
V
S×V
0.893 0.513 0.681
NS NS NS
* * **
** ** **
0.043 0.031 0.013 0.086 0.026 0.038 0.063 0.034 0.241 0.453 0.047 0.039 0.092
NS NS NS NS NS NS NS * NS NS NS * NS
NS NS NS NS NS * NS NS * * * NS NS
* * * NS NS * NS * * * ** ** *
0.036 0.042 0.041 0.045 0.311
* * NS * NS
* * * NS NS
* * * * NS
Different letters (a, b) within row differ significantly (*P < 0.05; **P < 0.01; NS: not significant, P > 0.05). S.E.M.: standard errors of the means. a Control group.
196
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
Table 3 Chemical and physical analyses of meats subjected to shower (S) and/or ventilation (V) treatments Ventilation
No
Yes
S.E.M.
Shower
Noa
Yes
No
Yes
Moisture (%) Protein (%) Ash (%) Fat (%) Collagen (%) pH WB shear force (kg)
69.55 15.35 0.68 12.42 a 0.64 5.94 11.26 a
70.33 15.50 0.69 12.25 a 0.67 5.75 10.54 a
70.33 15.55 0.70 12.23 a 0.65 5.73 9.32 b
71.14 15.41 0.71 11.53 b 0.62 5.77 9.67 b
0.414 0.087 0.341 0.216 0.023 0.092 0.024
Effects S
V
S×V
NS NS NS NS NS NS *
NS NS NS NS NS NS *
NS NS NS * NS NS *
Different letters (a, b) within row differ significantly (*P < 0.05; **P < 0.01; NS: not significant, P > 0.05). S.E.M.: standard errors of the means. a Control group.
surplus in their body as fat deposits, as reported by Sen et al. (2004) and Mader (2007). In carcass evaluation, the fat deposits were stored preferably as intramuscular fat (Nitter, 1975; Colomer-Rocher et al., 1987). The distribution of fat into the muscles of cooled kids was better when compared to the non-cooled (control) kids’ carcasses, so cooling has positive effects on the carcass quality in goats, as well (Table 2). The mean values belonging to the chemical analyses of the tissues taken from the carcasses are given in Table 3. There were not significant differences between the groups in terms of moisture, protein, collagen and pH (P > 0.05), while the fat contents were significantly different (P < 0.05). These findings matched with the data that were obtained during the carcass study. The fat contents of kids were cooled by both shower and ventilation lower than that of the other groups. Physical/chemical attributes of meats are given in Table 3, as well. There were significant differences in shear force (P < 0.05) of meats of different groups. When kids were
cooled by ventilation, their meat was tenderer than the other kids’ meat. Shear force values were in the range of 4.32–5.54 kg/cm2 in groups which were cooled by shower or ventilation. These values were low compared to 6.0 kg/cm2 observed by Johnson et al. (1995), who were cited by Dhanda et al. (1999), while being quite a lot higher than those of the findings of Dhanda et al. (1999). However, the muscles of control kids were higher than the other treatment groups and also than the findings of Dhanda et al. (1999). Reason of this variation is intramuscular fat contents of the muscles (Colomer-Rocher et al., 1987). The organoleptic panel results of the meat samples taken from kid carcasses are given in Table 4. It was observed that the raw meat samples were similar in terms of colour and odour in all groups, but the marbling rates of the kids somewhat cooled, especially of the kids cooled with a ventilation, were higher than the control ones. The marbling of control kids were worst than the cooled kids (P < 0.05) which means that intramus-
Table 4 Organoleptic panel results Traits
Control
Shower
Ventilation
Shower and ventilation
S.E.M.
Significance
Raw Colour Odour Marbling
4.25 5.00 3.75 b
4.25 5.00 4.00 a
4.00 5.00 4.75 a
4.75 4.75 5.00 a
0.125 0.250 0.085
NS NS *
Fried Odour Flavour Chewiness
5.00 3.25b 3.00b
5.00 4.75 a 4.50 a
5.00 5.00 a 4.00 a
5.00 5.00 a 4.75 a
0.000 0.085 0.269
NS * *
Boiled Odour Flavour Chewiness
5.00 3.75b 3.00b
5.00 4.50 a 4.50 a
4.75 4.75 a 5.00 a
5.00 4.75 a 5.00 a
0.101 0.129 0.232
NS * *
S.E.M.: standard errors of the means; Different letters (a, b) within row differ significantly (*P < 0.05; NS: not significant, P > 0.05).
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
197
Table 5 Economic analyses of shower and ventilation application on male kids under heat stress Ventilation
No
Shower
No
Weight gain (USD/(kid trial))a Feed consumption (USD/(day kid))b Water (USD/(m3 day 8 kids))c Electricity (USD/(kwh day kid))d
0 0 0 0
Total
0
a b c d
Yes Yes
No
Yes
+11.15 −1.99 −0.1 0
+21.15 −1.75 0 −0.5
+13.53 −2.31 −0.1 −0.5
+9.06
+18.90
+10.62
1 kg live weight 4.1 USD. 1 kg concentrate 0.23 USD. 1 m3 drinking water 0.2 USD (4 m3 days for 8 kids). 1 kw/h electricity 0.5 USD (total 8 kwh/(day/8 kids)).
cular fat distribution is also worst than cooled kids. The taste and the tenderness of boiled and fried meat samples taken from the kids cooled with a shower (4.50 vs. 5.00) were better than ventilation treatment groups (P < 0.05). Thus the meat flavour of the kids which were cooled either by ventilation or by shower was better than the control ones. There was no research that could available to discuss these findings. Results of the economic analyses of this experiment are summarized in Table 5. When the value given in the control group was zero, all of the cooled individuals were more profitable than the control kids. The numbers given in Table 5 just represent one kid; therefore, when it is estimated for eight individuals, this will mean 152.2 USD higher profits, which cannot be overlooked considering profitability. 4. Conclusion The results obtained in the present study indicate that different cooling methods, including shower and ventilation, lead to different fattening scores and different carcass qualities. Additionally, supplying a shower and ventilation improved weight gain by +2.72–3.16 kg and feed consumption by −2.8 to 4.8 kg. Also, the carcass quality and total muscle and fat distribution of the carcasses improved. The results have provided some important clues and indicators on how to promote fattening performance and the carcass quality of the kids in the Mediterranean region, where hot and humid weather prevails. This was quite clear especially in cooling only by ventilation and shower, which resulted in the best performances of all the groups. Although showering was profitable, the results were much better when ventilation was also applied. Economic analyses also supported the findings, and it was seen that an individual kept cool with ventilation increased the profit by 19 USD, compared to
an individual which was not kept cool. This number is quite important considering profitability. Acknowledgements This study was supported by VHAG-2083 Project of TUBITAK. Authors’ thank Ahmet Koluman, Murat Gorgulu, Mehmet Mamger and Mary Lynn Varner for their valuable help. References AOAC, 2000. Moisture content. 950.46. In: Official Methods of Analysis, 17th ed. Association of Official Analytical Chemists, Gaithersburgh, MD. Beede, D.K., Collier, J., 1986. Potential nutritional strategies for intensively managed cattle during thermal stress. J. Anim. Sci. 62, 543–548. Bucklin, R.A., Turner, L.W., Beede, D.K., Bray, D.R., Hemken, R.W., 1991. Methods to relieve heat stress for dairy cows in hot, humid climates. Appl. Eng. Agric. 7 (2), 241–246. Colomer-Rocher, F., Morand-Fehr, P., Kirton, A.H., 1987. Standard methods and procedures for goat carcass evaluation, jointing and tissue separation. Livest. Prod. Sci. 17, 149–159. Darcan, N., Guney, O., 2002. Effect of spraying on growth and feed efficiency of kids under subtropical climate. Small Rumin. Res. 43, 189–190. Darcan, N., Cedden, F., Cankaya, S., in press. Spraying effects on goat welfare in hot and humid climate. Ital. J. Anim. Sci. Dhanda, J.S., Taylor, D.G., Murray, P.J., McCosher, J.E., 1999. The influence of goat genotype on the production of capretto and chevon carcasses. 2. Meat quality. Meat Sci. 52, 363–367. Goncu, S., Ozkutuk, K., 2003. Shower effect at summer time on fattening performances of black and white bullocks. J. Appl. Anim. Res. 23 (1), 123–127. Huber, J.T., Higginbotham, G., Gomez-Alarcon, R.A., Taylor, R.B., Chen, K.H., Wu, Z., 1994. Heat stress interaction with protein, supplemental fat and fungal cultures. J. Dairy Sci. 77, 2080–2090. Igono, M.O., Johnson, H.D., Steevens, B.J., Krause, G.F., Shanklin, M.D., 1987. Physiological, productive and economic benefits of shade spray and ventilation system versus shade for Holstein cows during summer heat. J. Dairy Sci. 70, 1069–1079.
198
N. Darcan, S. Cankaya / Small Ruminant Research 75 (2008) 192–198
Kinne, M., 2007. Breaching heat stress comfort zones. http:// kinne.net/heatstrs.htm, last access date: October 15, 2007. Knizkova, I., Kunc, P., Koubkova, M., Flusser, J., Dolezal, O., 2002. Evaluation of naturally ventilated barn management by thermographic method. Livest. Prod. Sci. 77, 349–353. Kocak, H., 1995. Effects of castration on fattening performances of German fawn × hair crossbred kids. Master Thesis. No.: 949. Institute of Basic and Applied Sciences, Cukurova Univ., Adana, Turkey. p. 48. Mader, T.L., 2007. Heat stress effects on feedlot cattle and mitigation strategies. In: 22nd Annual Southwest Nutrition & Management Conference, Tempe, AZ, Feb 22–23 2007. Nitter, G., 1975. Preliminary results with intensive fattening of young goats. Kleinviehzuehter 23, 316–320. Regula, G., Danuser, J., Spycher, B., Wechsler, B., 2004. Health and welfare of dairy cows in different husbandry systems in Switzerland. Prev. Vet. Med. 66, 247–264. Rosen, S., 1992. Heat stress management in Israel. Extension Service, Ministry of Agriculture, Extensions, Beit Shean, Israel, pp. 83–90.
Rout, P.K., Mandal, A., Singh, L.B., Roy, R., 2002. Studies on behavioral patterns in Jamnapari goats. Small Rumin. Res. 43, 185–188. Sarri´es, M.V., Beriain, M.J., 2005. Carcass characteristics and meat quality of male and female foals. Meat Sci. 70 (1), 141–152. Sen, A.R., Santra, A., Karim, S.A., 2004. Carcass yield, composition and meat quality attributes of sheep and goat under semi-arid conditions. Meat Sci. 66, 757–763. Serbester, U., Gorgulu, M., Kutlu, H.R., Yurtseven, S., Arieli, A., Kowalski, Z.M., 2004. The effects of sprinkler + ventilation, fish meal or dietary fat on milk yield and milk composition of dairy cows in mid lactation during summer. J. Anim. Feed Sci. 14, 639–653. Silanikove, N., 1992. Effects of water scarcity and hot environment on appetite and digestion in ruminants: a review. Livest. Prod. Sci. 30, 175–194. SPSS Inc., 1999. SPSS for Windows. Release, 10.0. Copyright SPSS Inc., Chicago, USA. Yousef, M.K., 1987. Principles of bioclimatology and adaptation of livestock. Elsevier Publ., Holland, WAS, B5, 17–31.