The reproductive cycle test

(INCORRECT. PMSG (Pregnant Mare Serum Gonadotropin) is a hormone extracted from pregnant mare serum that has LH (luteinizing hormone) and FSH (Follicle Stimulating Hormone) properties)

(INCORRECT. The prostaglandins are secreted by the uterus, enabling lysis (breaking down) of the corpus luteum.)

(CORRECT. This is the hormone which, by blocking the hypothalamus-pituitary system, prevents any ovulation outside heat.)

(INCORRECT. PMSG (Pregnant Mare Serum Gonadotropin) is a hormone extracted from pregnant mare serum that has LH (luteinizing hormone) and FSH (Follicle Stimulating Hormone) properties.)

(Whilst on average the first signs of heat appear around 20 to 25 days after calving, some animals may be on heat from the first week following calving onwards.)

(The first ovulation after calving can be early (from 8 days onwards) but is not often accompanied by heat. When they do appear they are often discrete.)

(Even if oestrus starts in the month that follows calving, the cow will not be inseminated then. However, detection of the first period of heat will make detection of following periods of heat easier.)

(This sign can be observed at times around the actual period of heat, but it is not one of the most reliable signs.)

(This is the defining criteria for telling whether a cow is on heat or not.)

(On the contrary, the motor activity of a cow on heat increases; it can be measured and recorded by a pedometer.)

(This criteria is not specific, but can frequently be observed when an animal is on heat.)

(Heat lasts from 8 to 24 hours and ovulation occurs between 6 to 10 hours after the end of heat.)

(Heat lasts from 8 to 24 hours and ovulation occurs between 6 to 10 hours after the end of heat.)

(Heat lasts from 8 to 24 hours and ovulation occurs between 6 to 10 hours after the end of heat.)

(The duration of heat in heifers is shorter than in cows.)

(Heat does not last for more than 24 hours in cows.)

(Duration of heat in cows is on average 14 hours +/- 5 hours; 45% of heat starts in the evening or at night; 16% lasts for less than 8 hours.)

(First heat can occur 8 days after calving; this is much too early for insemination to be carried out since uterine involution has not yet finished.)

(Whilst involution may appear to have finished in macroscopic terms. In reality it hasn´t completely finished; it is therefore advisable to wait for 10 to 15 days so that the uterus is ready to receive embryos.)

(Prior checks on whether uterine involution is finished and if the animal has a satisfactory body condition are desirable.)

(Prior checks on whether uterine involution is finished and if the animal has a satisfactory body condition are desirable.)

(Age is not the main criteria when breeding a heifer for the first time. Weight is the most important to be taken into account.)

(Age is not the main criteria when breeding a heifer for the first time. Weight is the most important factor to be taken into account.)

(This is the weight that should be reached before breeding a heifer for the first time.)

(This is the weight reached at puberty. However, it is still too early for breeding a heifer for the first time, because the animal´s sexual cycle is not yet regular, and her physical development is insufficient.)

(Resumption of follicle growth is practically identical for both types of female.)

(If a suckler cow is milked in the same way as a dairy cow, heat starts earlier after calving.)

(The first period of heat is often not very visible as much in dairy cows as it is in suckler cows.)

(. If a suckler cow is milked in the same way as a dairy cow, heat starts earlier after calving.)