AviagenBrief. Spiking Programs to Improve Fertility. Summary. November 2010

Transcription

1 AviagenBrief November 2010 Spiking Programs to Improve Fertility North American Technical Team This article has been written specifically for poultry producers in North America. The advice provided is therefore relevant to the management strategies employed within the North American region. However, the recommendations given are expected to be useful and informative for other world regions. Please discuss the relevance of this information for your region with your local Technical Manager. Summary Introduction If managed effectively spiking can help to improve the decline in late fertility. The introduction of a number of new, generally younger males, into a flock upsets the flock s social pattern. This improves the mating activity of the males, and overall flock fertility and flock output can be increased. However, a failure to manage spiking programs correctly can lead to adverse effects on performance. Sourcing Spike Males There a number of methods used to source spike males: 1. Sourcing spike males from 25-week old flocks. Males are moved with the females at transfer, light stimulated and fed to achieve normal weight gain until 25 weeks of age. During the 25th week the largest framed and best fleshed males are selected to spike an older flock. 2. Sourcing spike males from a spike male farm. Males are removed from the flock at transfer and placed into a separate house or farm to be conditioned. Upon reaching maturity and the correct body weight males are used to spike an older flock. 3. Sourcing spike males from 21/22-week old flocks. At transfer males are graded. The large males are used to spike an older flock. The average males are used for mating up the females with which they were reared. The small males undergo further conditioning and are used to spike an older flock as they reach the correct body weight and maturity. 4. Sourcing spike males from an older flock. This method is only used if there is a shortage of males and should not be used routinely. Males from a mature flock are removed 1 week prior to depletion and used to spike a younger flock. Key Points Whatever the system used to source spike males the following points are key to ensuring that spiking is completed successfully. A flock should be spiked when the male ratio declines to 8 males per 100 females. Depending on male mortality rate, the number and timing of spikes will vary. Routinely flocks should be spiked at 35 and 50 weeks of age. During spiking, the male ratio should be increased by a minimum of 20%, but a mating ratio of 10 males per 100 females should not be exceeded. Prior to spiking, check the condition of the existing males in the flock and remove any that are unproductive. Males to be used for spiking should be in good condition (fleshing, body weight and frame size), have a fully developed comb and wattle (intense red in color) and good legs (strong and straight with no deformities). Spike males should be large enough in size to compete with the mature males of the flock into which they are being introduced. They should be at least the average weight of the males in that flock and a minimum weight of lbs ( kgs). Males to be used for spiking should be photostimulated for at least 3 (ideally 4-5) weeks before being introduced into an older flock. A temporary reduction in feeder height and increase in feed intake may be required to ensure that the spike males are able to find food upon introduction to a new flock. And finally, males to be used for spiking must be free from disease and parasites. 1

2 % HATCH The remainder of this article provides more detail on the points summarized on page one. Spiking Programs to Improve Fertility Introduction Spiking can successfully deliver a positive response in late fertility, leading to an improved overall flock performance and output (Figure 1). Figure 1: An example showing how flock fertility can be maintained with the addition of spike males to a flock MALE SUMMARY Male Ratio Hatch Goal % Weekly Hatch Male AGE Introducing a number of new (generally younger) males into a flock upsets the flock s social patterns, stimulating the mating activity of the males and improving overall flock fertility. However, if spiking programs are not managed correctly adverse effects on flock performance may occur. The aim of this article is to provide management advice on how to successfully run spiking programs to optimize flock fertility and output. Sourcing Spike Males Below is a summary of the various methods which can be used to source spike males. Option 1: Sourcing males from 25-week old flocks This is the original method of sourcing spike males and has been in use for some years. It is generally used in smaller operations. All males are moved into the breeder house with the females. This gives a high initial male to female ratio of around males per 100 females at 22 weeks. The flock is light stimulated and fed normally for weight gain to mature both the females and males. During the 25th week, the largest framed and heaviest fleshed males are selected and used for spiking older flocks. Male selection is normally done early in the morning when the males are at the feeder and male size can be easily established. The number of males to be removed is pre-determined so that males per 100 females are left in the younger breeder flock. This system works well because the spike males are conditioned prior to the spike and can therefore be distributed into the mature flock with no further conditioning. Selecting the largest framed males 9.50 in the flock is key to this method 9.00 being successful. MALE RATIO 8.50 Option 2: Sourcing males from spike male farms 8.00 In this method of sourcing spike males, the males are removed 7.50 from the flock at transfer. They are then placed in a separate 7.00 male farm equipped with identical (or at least similar) feeding and watering equipment to that used in the laying farm. A lighting program to stimulate maturity is implemented and the male flock is fed so that it is able to attain a body weight similar to that of the males in the flock to be spiked, achieving a weight of lbs ( kgs) at weeks of age. Males selected for spiking should be mature, have good body condition and frame size, be of an appropriate weight and have good feet and legs. Two selections are normally done since males will reach adequate maturity and weight at different times. The spike male farm is the best method for conditioning and light stimulating males, but carries the highest risk of spreading disease into laying flocks. For this reason spike males introduced from a separate male farm should be tested for disease and examined for parasites. Male aggression can also sometimes be a problem with this method so it is important to monitor male aggression after the spike males are introduced into the flock. 2

3 Option 3: Sourcing males from 21/22-week old flocks In this method, males are caught and graded into 3 pens (large, average and small framed males) when the flock is transferred to the breeder house. This allows appropriately sized males to be put with similar sized females. Males graded as large are used to spike a mature flock, males graded as average are mated with the females of the flock with which they were reared and small males undergo further conditioning. After grading, the large males are removed from the flock and moved into the laying house with the mature flock they are to be used to spike. They are placed into a separate male pen at one end of the house to be conditioned; i.e. grown to an appropriate weight (at least the average weight of the males in the flock, minimum of lbs ( kgs) and condition, and light stimulated to maturity. Once they reach maturity these males can then be used to spike the mature flock as required. The remaining immature males are given extra time in the pen to achieve target weight gains and reach maturity. The males graded as average and small stay with the flock with which they were reared. The average sized males are mated with the females of the flock. The males graded as small are placed in a separate male pen at one end of the laying house for further conditioning. Once the small males reach an appropriate size and maturity they can then be introduced into the flock as necessary. An example of a separate male pen built at one end of a laying house is given in Figure 2. The male pen shown in Figure 2 has a petition across the entire width of the house taking in the slats, nests and feeding system. The females are removed from the pen, the nests are closed off and the female feeder system is used to feed the males. The males are fed from the female feeder by removing inches ( cm) per male of restriction grill, adding the male head count to the female head count and increasing feed amounts appropriately. Feeding males from the female feeder can result in some males losing too much weight after release as they are unable to find the male feeders; these males may never become reproductive. Figure 2: Example of a separate male pen positioned at one end of the laying house Some operations petition off the male pen only in the scratch area and use the male feeder for the males. This may be beneficial in training the spike males to use male feeders, but if male feeding space is inadequate it can increase male aggression. Additional uses for the separate male pen The male pen system may also be used to condition the smaller males in a young flock and increase the male:female ratio coming into peak egg production. Here, the females are mated with 7 average graded males per 100 females. The equivalent of 3 males per 100 females is placed in the male pen to gain weight. These males will be used to increase the mating ratio of the flock at weeks of age. The male pen is then free to be used to condition spike males (large graded males from a young flock) to be used later in the lay cycle. So it can be used multiple times in the life of a flock. Option 4: Sourcing males from mature flocks This method of sourcing spike males should only be used if male numbers are low and should not be used routinely. If a shortage of males occurs, males may be removed from a mature flock 1 week prior to depletion and moved back to a younger aged flock of 45 weeks of age or older. Ideally these males should be selected from those that were used to spike the flock last but sometimes, if their condition is good, 64-week old males can be selected. Males must be selected for weight, activity level, leg strength, foot pad quality and absence of parasites, specifically fowl mites. Blood screening for disease must also be completed prior to movement to a younger flock. Managing the Spiking Process When to spike The ideal male to female mating ratio is 10 males to every 100 females. The number of times a flock should be spiked will depend on male mortality/cull rate. The minimum mating ratio varies depending on the restriction of male body weight in the breeder house, but in the US where males tend to be kept on a lighter body weight profile 8 males per 100 females is considered the minimum male:female mating ratio. When this ratio is reached (through the removal of non-working males as part of the normal male management routine or as a result of mortality) spiking should occur. Normally a minimum of 2 spikes, at 35 and 50 weeks of age, are completed during the production period. At spiking the male ratio should be increased by a minimum of 20% but the male to female ratio after spiking should not exceed 10 males per 100 females. For example, if the pre-spiking mating ratio is 8 males to 100 females, the ratio would be increased to males per 100 females during spiking. A shortage of males may require more spikes to be completed with lower numbers of males added. Spike males should be introduced to a flock in the evening or early morning. 3

4 Spike male weight requirements Spike males should be a minimum weight of lbs ( kgs) and at least the average weight of the males of the flock into which they are being introduced; spike males need to be large enough (body weight and frame size) to compete with mature males. They must have some excess weight which will be lost as they adapt to a new flock, but when growing spike males it is important that conformation is maintained and assessed, and that males are not allowed to get too fat. Once introduced to the flock, spike males should be weighed separately for at least 4-6 weeks to ensure they are eating (check crop fill) and gaining weight. It is therefore important that spike males are easily identified. This can be done by marking them with a spot of dye on the back. In addition, spike males can be identified by their shank color which will be deeper and spur length which will be shorter compared to the more mature males of the flock. Spike male condition Males to be used for spiking should be of an appropriate body weight and frame size and in good condition (fleshing). They should be dominant, mature males with a fully developed comb and wattle (which are intense red in color). In addition they should have good legs; straight, with no bent toes and footpads that are clean and free from abrasions. (See Figure 3). Importantly males to be used for spiking should be free from disease and parasites. Figure 3: Attributes of a good quality male which can be used for spiking. Males should be in good condition (picture on left), have a fully developed comb and wattle (center picture), and have good legs (picture on right). Male feeder systems and feeding rates Male feeding space is not normally an issue for spike males; it is recommended that breeder houses should be designed with enough feeder space for 8-10 males per pan at 25 weeks. However, feeder height can be a problem for newly introduced spike males. It is vital that spike males get access to the feed; this may require an adjustment of male feeder height and an initial increase in feed amounts. Feeder height should be lowered by 4-6 inches (10-15 cm) for up to a week if there are issues with spike males reaching the feeders. To ensure that spike males maintain condition during transfer to a new flock feed amounts should be increased by 30% for the first 3 days after the spike males have been introduced to a flock. This will increase feed consumption time and give the spike males more time to find the feed. Visiting the flock at feeding time is the best way of determining if spike males are finding food. Lighting Males should be photostimulated for at least 3 weeks (but ideally for 4 or 5 weeks) prior to being introduced into a mature flock. This will ensure that they are mature at the point of introduction. If conditioned in the same house as the females they will be light stimulated to maturity using the normal female lighting program. If the males are conditioned on a separate male farm consult your Technical Manager for a suitable lighting program. In either case, the lighting systems in place must be capable of producing a minimum light intensity of 3 foot candles (30 lux). Cull males Non-working males should be removed from the flock daily as part of the normal male management routine. However, if routine culling is not done it is vital that the males in the flock are reviewed prior to spiking, and any non-working males removed. A non-working or cull male is one which is pale around the eyes with a pale comb and wattles, a dry /pale vent, or poor legs (see Figure 3 on next page). 4

5 Figure 3: Attributes of non-working or cull males which should be removed from a flock. Males to be removed will be pale around the eyes and have a pale comb and wattle (picture on left), a pale/dry vent (center picture) or poor legs/ feet (picture on right). Conclusions Spiking, if managed properly can be used to successfully improve the fertility of a flock. There are a number of different systems that can be used to source spike males but in all cases it is important that males are: given an appropriate period of conditioning prior to being added to a mature flock, of appropriate condition, frame size, body weight and are mature, given appropriate feeding space and feed amounts upon introduction to the new flock, are monitored carefully upon introduction to a new flock, are disease and parasite free AVN-028