Effects of Different Breeds, Number of Squabs and Temperature on Production Performance of Pigeons

Qingping TANG*, Chunyu MU, Zuofu QU2, Rui ZHANG, Zhu BU

1. Jiangsu Institute of Poultry Science, Yangzhou 225125, China; 2. Jiangsu Weitekai Pigeon Co., Ltd., Jiangyin 214400, China

Abstract To explore the effects of breeds, number of nurturing squabs, and temperature on nest feed conversion ratio and analyze the effects of number of nurturing squabs on parent pigeon body mass, fertility rate, and laying intervals, 5 widely used breeds of pigeon were nurtured under the condition of natural laying and hatching in this research. In each breed, 24 pair pigeons nurturing 1, 2, 3, and 4 squabs were chosen to measure the production performance, respectively. The results indicated that different numbers of nurturing squabs had a significant effect on parent pigeon body mass changes and survival rate of 28- d old squabs (P<0.05); the nest feed conversion ratio of breeds nurturing 1 squab (7.58) was extremely significantly higher than those of nurturing 2, 3, and 4 squabs (P<0.01); the nest feed conversion ratio of breeds nurturing 2 squabs (4.75) was extremely significantly higher than those of nurturing 3 (3.95) and 4 squabs (3.75) (P<0.01); there was no significant difference between breeds nurturing 3 and 4 squabs (P>0.05). Laying intervals of breeds nurturing 4 squabs (43.8 d) were significantly higher than those of nurturing 3 (37.4 d), 2 (35.4 d), and 1 (33.8 d) squabs (P<0.05). Nest feed conversion ratio significantly increased with the decrease of environment temperature (P<0.05). The breed showed no effect on the nest feed conversion ratio. In production, nurturing 3 squabs of parent pigeons is appropriate. In some cold areas in winter, cold protection measures should be taken.

Key words Pigeon, Number of nurturing squabs, Temperature, Nest feed conversion ratio, Production performance

1 Introduction

With 40 years of development, China’s pigeon breeding industry has accounted for more than 80% of the world’s total, making China become the world’s number one pigeon breeding country. With people’s consumption levels constantly increasing, pigeons as high- end foods are becoming more and more popular, thus the pigeon breeding has a good development prospect[1]. The expansion of market demand and the need to continuously increase production efficiency have promoted the use of technologies such as nurturing squabs, assorted egg hatching, nurse pigeon, and artificial hatching,etc. At present, "2+3" and "2+4" are widely used in production[2]. The main end product of the production of meat pigeons is the squab. For meat poultry, feed conversion ratio is the optimum indicator of economic benefit. However, due to the special production habits of pigeons, there is still no method to directly calculate the feed conversion ratio. In order to adapt to the actual production of pigeons, it is necessary to improve the feed conversion ratio into the nest feed conversion ratio[3]. According to the studies of Zhang Jianpingetal.[4]and Cai Chunfangetal.[5], the production benefits of pigeons nurturing 3 squabs was better than that nurturing 4 or 2 squabs, but they did not consider the changes in the body mass of parent pigeons when determining the feed conversion ratio.

In this study, through nurturing 5 widely used breeds of pigeon under the condition of natural laying and hatching, we explored the effects of breeds, number of nurturing squabs, and temperature on nest feed conversion ratio and analyzed the effects of number of nurturing squabs on parent pigeon body mass, fertility rate, and laying intervals.

2 Materials and methods

2.1 Test pigeons and feeding managementWe selected one year older European E series pigeons (E), white Carnean K series pigeons (K), white King W series pigeons (W), Suwei parent generation pigeons (SW), silver King pigeons♂× Texan pigeons ♀ (YT) raised by Jiangsu Weitekai Pigeon Co., Ltd., normally bred, and with 1 d difference between the last nest of egg laying date, and 24 pairs for each group. With each group, the breeding pigeons of the same hatching date were intertwined with each other, nurturing 1, 2, 3 and 4 squabs respectively, 6 pairs for each squab nurturing type. When the number of squabs was insufficient, the same breed (combination) squabs artificially hatched in the same period were used to complement. The record of daily production performance was made. A total of 4 nests of production data were collected, during which the parent pigeons did not nurture eggs. Instead, eggs were naturally hatched. Pellet feed+raw grain feed; dietary nutrition level: crude protein 15.7%, energy 12.32 MJ/kg; storage type feeding, free drinking, routine immunization. The test period was from August 9 to January 27 of the next year.

2.2 Measurement indicatorsThe measurement indicators included the nest feed conversion ratio, egg laying intervals, fertility rate, squab survival rate, body mass change of male pigeon, body mass change of female pigeon, and body mass of 28- d old squab. The production records were made in pairs, and the performance of the population was counted after the experiment. The measurement was carried out in accordance with the method in Technical Specifications NY/T 823- 2004[6].

The method of measuring the nest feed conversion ratio was as follows: measured the body mass of 0- d old squab; measured the body mass of male and female pigeons on the same day of laying the first squab; after emptying the feed chute, started making record of the feeding weight. After slaughter of 28- d old squabs, removed the feed, and measured the body mass of male pigeons, female pigeons, and each squab.

NFCR=Ws/(W28-W0)

whereNFCRrefers to the nest feed conversion ratio;Wsdenotes the feeding weight of one nest of pigeons (parent pigeons+all squabs);W28denotes the body mass of one nest of pigeons (parent pigeons+all squabs) at the time of slaughter of 28- d old squabs;W0denotes the body mass of one nest of 0- d old pigeons (parent pigeons+all squabs).

2.3 Data processingData were analyzed using One- way ANOVA with the aid of statistical software SPSS 20.0. And data were expressed in Mean±SD.

3 Results and analysis

3.1 Effects of number of nurturing squabs on production performance of pigeonsTaking 5 groups as a population, we analyzed the effects of number of nurturing squabs on indicators including the nest feed conversion ratio. From Table 1, it can be seen that all types of the number of nurturing squabs had significant effects on the changes in the body mass of male pigeons and female pigeons, nest feed conversion ratio, and survival rate of 28- d old squabs (P<0.05).

Table 1 Effects of number of nurturing squabs on production performance of pigeons

Number of nurturingsquabs∥pcsChange in body massof male pigeon∥gChange in body massof female pigeon∥gNest feed conversionratioChange in body massof 28-d old squabs∥gSurvival rate of28-d old squabs∥%1-15.5±17.3ac-0.7±3.2b7.58±1.24c547.70±79.7a100±0b2-7.2±9.5bc0.0±9.5b4.75±0.89b555.62±73.97a90±2a3-22.3±18.6ac-1.1±23.5b3.95±0.79a545.88±59.13a95±13b4-48.1±27.1a-22.8±29.4a3.75±1.36a518.17±76.40a85±26a

Note: the same letters in the same column represent insignificant difference (P>0.05), and different letters represent significant difference (P<0.05). The same as belows.

3.2 Effects of different number of nurturing squabs on fertility rate and laying intervalsThe laying interval (the time between the male pigeons laying two adjacent eggs, expressed in d) is inversely proportional to the number of laying eggs. The shorter the laying interval, the more eggs are laid[3]. The laying intervals can be accurately recorded on the production record note in the pigeon shed and the recording is simple, so the laying interval is a most visual indicator reflecting the reproductive performance of pigeons.

From Table 1, it can be seen that after the end of a feeding period, the more the nurturing squabs, the more the decline of body mass of parent pigeons, showing that the physical consumption of the pigeons will inevitably affect their reproductive ability. Taking 5 groups as a population, we selected breeding pigeons that had consecutive 3 or more nests, and analyzed the effects of different number of nurturing squabs on the laying intervals and fertility rate.

From Table 2, it can be seen that the number of nurturing squabs did not exert significant effect on the fertility rate of parent pigeons (P>0.05); the laying interval of nurturing 4 squabs was significantly greater than that of nurturing 3 and 2 squabs and 1 squab (P<0.05).

3.3 Effects of breeds on production performance of pigeons

Because the combination of number of nurturing squabs in each breed was the same, we could ignore the effect of number of nurturing squabs between groups and considered only the effect of the breed, and combined the data of 4 nests to analyze.

According to Table 3, there was no significant difference in the change in body mass of male pigeons, nest feed conversion ratio, and survival rate of 28- d old squabs between 5 breeds (combinations) (P>0.05), while there was significant difference in the change in body mass of female pigeons and the body mass of 28- d old squabs (P<0.05).

Table 2 Laying intervals and fertility rate of different number of nurturing squabs of pigeons

Number of nurturingsquabs∥pcsLaying intervals∥dFertility rate∥%133.8±2.7a 100±0a235.4±2.9a 98±5a337.4±5.2a 99±4a443.8±8.5b97±5a

Table 3 Production performance of 5 breeds of pigeons

GroupChange in body massof male pigeon∥gChange in body massof female pigeon∥gNest feed conversionratioChange in body massof 28-d old squabs∥gSurvival rateof 28-d old squabs∥%E-28.6±45.4a -5.7±19.0a5.45±1.89a 596.5±78.7c93±17aK-16.1±34.1a -12.8±25.8a 4.77±1.82a 552.2±63.9b92±18aYT -16.9±29.4a -5.9±19.7a 4.89±1.76a 522.9±58.7a 93±20aW -18.9±36.2 a-1.0±20.8ab5.06±1.70a 527.9±70.8a95±14aSW -15.4±36.6a 13.0±27.3b5.20±1.68a545.4±62.7ab95±14a

3.4 Effects of breed on the nest feed conversion ratioFrom Table 4, it can be seen that there was significant difference in the nest feed conversion ratio between different number of nurturing squabs in each group (P<0.05). Especially, the pigeons of nurturing 1 squab had large nest feed conversion ratio.

Table 4 Nest feed conversion ratio of 5 breeds of parent pigeons with different number of nurturing squabs

GroupNest feed conversion ratioNurturing 1 squabNurturing 2 squabsNurturing 3 squabsNurturing 4 squabsE7.69±0.96b4.92±1.19a 4.08±1.18a 3.37±0.44aK8.04±1.15c4.32±0.63b3.89±0.80ab3.00±1.15aYT7.73±0.67b4.75±1.08a 3.89±2.37a 3.03±3.40aW 8.27±0.85b4.68±0.77a 4.20±0.58a 4.08±1.77aSW6.94±1.58c5.09±0.65b4.26±0.55ab3.74±0.75a

3.5 Effects of temperature on the nest feed conversion ratio

Since there was only one day difference between the laying time of the selected parent pigeons, the first nest basically appeared around August 25, which was relatively concentrated. However, due to factors such as individual difference, number of nurturing squabs, and breeds, the subsequent 3 nests of laying time gradually showed gap. Till the end of the experiment, some parent pigeons only laid 3 nests of eggs. But for the purpose of statistical data, we took the data of parent pigeons with relatively concentrated laying time as one nest, and finally we counted a total of 4 nests of data. The entire experiment period extended about 6 months, from the end of August (the temperature was moderate) to the later days of January in the next year (the temperature was low). Taking the nest (temperature) as the influencing factor, we analyzed data and explored the effects of temperature on the nest feed conversion ratio. Without considering the breed and number of nurturing squabs, we took 5 groups as a population.

Table 5 Nest feed conversion ratio of different nests of parent pigeons

NestSample sizeNest feed conversion ratio1824.02±1.00a2985.24±1.63b3905.54±1.96bd4786.16±1.83cd

From Table 5, it can be seen that the nest feed conversion ratio significantly increased with the decrease of environment temperature, the difference was significant (P<0.05). The nest feed conversion ratio of the first nest was only 4.02, extremely significantly lower than 6.16 for that of the fourth nests (P<0.01).

4 Discussions

Pigeons belong to altrices. In natural production, 0-28 d old pigeons need to be nurtured by parent pigeons, the squabs and parent pigeons are inseparable, so the feed consumption of the squabs and the parent pigeons is difficult to distinguish. Besides, when the parent pigeons are feeding squabs, their body mass also changes (the body mass will increase if taking too much feed and the body mass will decrease in case of excessive consumption in feeding squabs). In this case, using the feed conversion ratio in the feeding period will be more accurate than using the nest feed conversion ratio.

4.1 Effects of number of nurturing squabs on production performance of pigeonsFrom Table 1, it can be known that different number of nurturing squabs showed no significant effect on the body mass of 28- d old squabs (P>0.05), but the body mass of pigeons nurturing 2 squabs (555.6 g) >that of nurturing pigeons nurturing 1 squab (547.7 g) >that of nurturing pigeons nurturing 3 squabs (545.9 g) >that of nurturing pigeons nurturing 4 squabs (518.2 g). After the end of parent pigeons feeding the squabs, the body mass of all parent pigeons decreased, the change in body mass of male pigeons nurturing 4 squabs (-48.1 g) was significantly greater than that nurturing 2 squabs (-7.2 g) (P<0.05), and the change in body mass of female pigeons nurturing 4 squabs (-22.8 g) was significantly greater than that nurturing 2 squabs (0.0 g), 1 squab (-0.7 g), and 3 squabs (-1.1 g) (P<0.05). The nest feed conversion ratio of breeds nurturing 1 squab (7.58) was extremely significantly higher than those of nurturing 2, 3, and 4 squabs (P<0.01); the nest feed conversion ratio of breeds nurturing 2 squabs (4.75) was extremely significantly higher than those of nurturing 3 (3.95) and 4 squabs (3.75) (P<0.01); there was no significant difference between breeds nurturing 3 and 4 squabs (P>0.05). The survival rate of 28- d old squabs for pigeons nurturing 1 and 3 squabs was significantly greater than that nurturing 2 and 4 squabs (P<0.05). It should be noted that the survival rate of that nurturing 2 squabs was lower than that nurturing 3 squabs, while that nurturing 4 squabs did not reduce the death rate, and the survival rate was only 85%, indicating that nurturing 4 squabs has exceeded the feeding ability of parent pigeons. The nest feed conversion ratio of pigeons nurturing 2-4 squabs obtained in this study (4.75-3.75) was slightly larger than that (4.15-3.74) obtained by Cai Chunyongetal.[5], possibly because we considered the reduction of body mass of parent pigeons, and significantly larger than (3.90-2.75) obtained by Zhang Jianpingetal.[6]through using white King pigeons and (2.27-2.70) obtained by Hu Weneetal.[7]. However, all these results showed the trend of decline of the nest feed conversion ratio with the increase of number of nurturing squabs. In this study, there was no significant difference in the nest feed conversion ratio between pigeons nurturing 3 squabs and 4 squabs. Combined with the survival rate and body mass of squabs, as well as the physical consumption of parent pigeons, the results of pigeons nurturing 3 squabs are better.

The study of the nest feed conversion ratio of poultry is mainly concentrated on chicken and duck, and few studies are related to pigeons. In this study, the nest feed conversion ratio of pigeons nurturing 3 squabs was about 4, while the nest feed conversion ratio of Suqin Yellow Chicken No.2 was only 2.15[8], Gansu Yellow Chicken was 2.93[9], Beijing duck was 2.69[10], Shenzhou No.1 Quail was 2.5-2.7[11], indicating that the feed conversion ratio of pigeons is lower compared with other types of poultry and the production cost is much higher.

4.2 Effects of different number of nurturing squabs on fertility rate and laying intervalsFrom Table 2, it can be seen that the number of nurturing squabs did not exert significant effect on the fertility rate of parent pigeons (P>0.05), all were higher than 95%; the laying interval of nurturing 4 squabs was significantly greater than that of nurturing 3 (37.4 d) and 2 squabs (35.4 d) and 1 squab (33.8 d) (P<0.05). From the long term production, nurturing 4 squabs will definitely influence the egg laying performance and reduce the egg laying number.

4.3 Effects of breed on the nest feed conversion ratioFrom Table 3, it can be seen that there was no significant difference in the change in body mass of male pigeons, nest feed conversion ratio, and survival rate of 28- d old squabs between 5 breeds (combinations). However, the body mass of 28- d old squabs was still highly consistent with the body mass of parent pigeons, and E>K>SW>W>YT. In addition, when considering the number of nurturing squabs, from Table 4, it can be known that there was significant difference in the nest feed conversion ratio between different number of nurturing squabs in each group (P<0.05), indicating that the key factor influencing the nest feed conversion ratio is the number of nurturing squabs.

4.4 Effects of temperature on the nest feed conversion ratio

The test site is located in Jiangyin City of Jiangsu Province. The first nest was from the end of August to the end of September at the room temperature of about 20-30℃; the second nest was from early October to early November at the room temperature of about 15-25℃; the third nest was from mid- November to mid- December at the room temperature of about 10-15℃; the fourth nest was from the end of December to the end of January at the room temperature of about 5-10℃.

According to Table 5, the nest feed conversion ratio significantly increased with the decrease of environment temperature, the difference was significant (P<0.05). The nest feed conversion ratio of the first nest was only 4.02, extremely significantly lower than 6.16 for that of the fourth nests (P=0). There was no significant difference between the second and third nests, the nest feed conversion ratio was 5.2-5.5. These indicate that at the low temperature, both parent pigeons and squabs need more energy to keep their body temperature. Therefore, under the same production conditions, warm protection for pigeon shed is favorable for reducing the feed consumption. This study also indicates that increasing the number of nurturing squabs can reduce the nest feed conversion ratio, but it will extend the egg laying intervals; nurturing 3 squabs can reduce the nest feed conversion ratio and will not reduce the survival rate of squabs; the pigeon breed has no influence on the nest feed conversion ratio; with the fall of environment temperature, the nest feed conversion ratio gradually increases. In actual production, nurturing 3 squabs of parent pigeons is appropriate. In some cold areas in winter, cold protection measures should be taken.